Samacheer Kalvi Class 12 Bio Botany Solutions Chapter 5 Plant Tissue Culture

Samacheer Kalvi 12th Bio Botany Guide Chapter 5 Plant Tissue Culture

 

I. Choose the correct answer from the given option:

 

Question 1. Totipotency refers to.
(a) capacity to generate identical plants.
(b) capacity to generate a whole plant from any plant cell/explant.
(c) capacity to generate hybrid protoplasts.
(d) recovery of healthy plants from diseased plants.
Answer: (b) capacity to generate a whole plant from any plant cell / explant
In simple words: Totipotency means a single plant cell can grow into a complete new plant. This ability makes tissue culture possible.

🎯 Exam Tip: Remember that totipotency is a fundamental concept in plant tissue culture, highlighting the versatility of plant cells.

 

Question 2. Micro propagation involves
(a) vegetative multiplication of plants by using micro-organisms.
(b) vegetative multiplication of plants by using small explants.
(c) vegetative multiplication of plants by using microspores.
(d) Non-vegetative multiplication of plants by using microspores and megaspores.
Answer: (b) vegetative multiplication of plants by using small explants.
In simple words: Micropropagation is like making many copies of a plant using tiny parts of it, called explants. It's a fast way to grow many plants.

🎯 Exam Tip: Key aspects of micropropagation include using small explants and achieving rapid vegetative multiplication in a controlled environment.

Match the Following

 

Question 3. Match the following

(a) 1-A, 2-D, 3-B, 4-C
(b) 1-A, 2-C, 3-B, 4-D
(c) 1-B, 2-A, 3-D, 4-C
(d) 1-D, 2-B, 3-C, 4-A
Answer: (c) 1-B, 2-A, 3-D, 4-C
In simple words: Totipotency is when a cell can make a whole new plant. Dedifferentiation is when a mature cell goes back to an early, growth-ready state. An explant is the tiny plant piece used to start a new culture. Differentiation is when cells change to do specific jobs in the plant.

🎯 Exam Tip: Understanding these core terms is essential for grasping plant tissue culture. Clearly distinguish between differentiation and dedifferentiation.

 

Question 4. The time duration for sterilization process by using autoclave is _______ minutes and the temperature is ______
(a) 10 to 30 minutes and 1250 C
(b) 15 to 30 minutes and 1210 C
(c) 15 to 20 minutes and 1250 C
(d) 10 to 20 minutes and 1210 C
Answer: (b) 15 to 30 minutes and 1210 C
In simple words: When we use an autoclave to make things germ-free, it usually takes between 15 to 30 minutes. The heat inside is kept at 121 degrees Celsius to kill all germs.

🎯 Exam Tip: Remember the standard temperature (121°C) and time range (15-30 minutes) for autoclave sterilization, as these are critical for successful tissue culture.

 

Question 5. Which of the following statement is correct.
(a) Agar is not extracted from marine algae such as seaweeds.
(b) Callus undergoes differentiation and produces somatic embryoids.
(c) Somatic embryoids are done by using mercuric bromide
(d) PH of the culture medium is 5.0 to 6.0
Answer: (b) Callus undergoes differentiation and produces somatic embryoids.
In simple words: A callus is a lump of plant cells. These cells can then change and form tiny plant embryos, called somatic embryoids, which can grow into new plants.

🎯 Exam Tip: The key correct statement highlights how callus tissue can develop into organized structures, which is a major step in plant regeneration.

 

Question 6. Select the incorrect statement from given statement
(a) A tonic used for cardiac arrest is obtained from Digitalis purpuria
(b) Medicine used to treat Rheumatic pain is extracted from Capsicum annum
(c) An anti malarial drug is isolated from Cinchona officinalis.
(d) Anti-carcinogenic property is not seen in Catharanthus roseus.
Answer: (d) Anti-carcinogenic property is not seen in Catharanthus roseus.
In simple words: The plant Catharanthus roseus (Periwinkle) actually *does* have properties that fight cancer. So, the statement saying it doesn't is wrong.

🎯 Exam Tip: Pay close attention to keywords like "incorrect statement" to avoid choosing the true option. Catharanthus roseus is known for its anti-cancer compounds.

 

Question 7. Virus free plants are developed from
(a) Organ culture
(b) Meristem culture
(c) Protoplast culture
(d) Cell suspension culture
Answer: (b) Meristem culture
In simple words: The meristem is a tiny tip of a plant that is usually free of viruses. By growing this part in a lab, we can get plants that are completely free from diseases.

🎯 Exam Tip: Meristem culture is a key technique for producing healthy, virus-free plants, especially important for commercial crops.

 

Question 8. The prevention of large scale loss of biological integrity.
(a) Biopatent
(b) Bioethics
(c) Biosafety
(d) Biofuel
Answer: (c) Biosafety
In simple words: Biosafety is about keeping living things, like plants and animals, safe from harm on a big scale. It ensures that new biotechnologies do not cause damage to nature or human health.

🎯 Exam Tip: Biosafety protocols are crucial in biotechnology to prevent harm to the environment and living organisms from experimental releases or modified organisms.

 

Question 9. Cryopreservation means it is a process to preserve plant cells, tissues or organs
(a) at very low temperature by using ether.
(b) at very high temperature by using liquid nitrogen
(c) at very low temperature of -196 by using liquid nitrogen
(d) at very low temperature by using liquid nitrogen
Answer: (c) at very low temperature of -196 by using liquid nitrogen
In simple words: Cryopreservation is like putting plant parts into deep sleep by freezing them at an extremely cold temperature, -196 degrees Celsius. Liquid nitrogen is used for this to stop all activities and keep them safe for a long time.

🎯 Exam Tip: The specific temperature (-196°C) and the use of liquid nitrogen are important details to remember for cryopreservation.

 

Question 10. Solidifying agent used in plant tissue culture is
(a) Nicotinic acid
(b) Cobaltous chloride
(c) EDTA
(d) Agar
Answer: (d) Agar
In simple words: Agar is a jelly-like substance that comes from seaweeds. In plant tissue culture, it is added to the liquid food mix to make it solid, so the plant cells have a firm surface to grow on.

🎯 Exam Tip: Agar is the most common and effective gelling agent in tissue culture due to its properties like stability and nutrient compatibility.

 

Question 11. What is the name of the process given below? Write its 4 types.
Answer: The diagram shows the process of plant tissue culture, from an explant growing into callus, then separating callus cells to form single cells or new plantlets, and finally regenerating a new plant. This process is known as plant tissue culture. Based on the explants used, plant tissue culture is classified as:
1. Organ culture
2. Meristem culture
3. Protoplast culture
4. Cell culture
In simple words: The pictures show how we grow new plants from tiny pieces in a lab. This is called plant tissue culture. We can do it in four main ways, depending on which part of the plant we start with: whole organs, meristem tips, cells without walls, or just single cells.

🎯 Exam Tip: When asked about processes with diagrams, first identify the overall process, then describe the key stages, and finally list any associated classifications or types.

 

Question 12. How will you avoid the growth of microbes in the nutrient medium during the culture process? What are the techniques used to remove the microbes?
Answer: To stop microbes from growing in the nutrient medium during plant tissue culture, we use sterilization. The main technique for this is autoclaving, which means heating the medium at 121°C and 15 psi pressure for 15 to 30 minutes. Other methods include chemical sterilization, using UV radiation, and filtering the air. These steps are vital to ensure the plant cells grow without contamination.
In simple words: We stop germs from growing by making everything super clean. We use a special hot machine called an autoclave to heat the plant food mix very high. We also use special chemicals, UV light, and filters to keep everything germ-free.

🎯 Exam Tip: Aseptic conditions are paramount in tissue culture. Always mention autoclaving as the primary method for media sterilization, along with other complementary techniques.

 

Question 13. Write the various steps involved in cell suspension culture
Answer: Cell suspension culture involves growing single plant cells or small groups of cells in a liquid medium. The steps are:
**Preparation steps:**
1. A small piece of callus (unorganized cell mass) is taken and placed into a liquid medium.
2. The liquid medium with the callus is then shaken on a rotary shaker to separate the cells.
3. Individual cells are separated from the larger callus tissue.
4. Finally, a suspension of these separated cells is extracted and used for culture. This method allows for a controlled environment for cell growth and study.
**Production of Secondary Metabolites:**
• Alkaloids, flavonoids, terpenoids, phenolic compounds, and recombinant proteins are examples of secondary metabolites.
• These are chemical compounds not directly needed by the plant for normal growth but have other uses.
• The process of producing these metabolites can be scaled up and automated using special bio-reactors for industrial production.
• Many techniques like biotransformation, elicitation, and immobilization are used to make cell suspension cultures better at producing these metabolites.
In simple words: To grow plant cells in liquid, we first put some plant cell lumps into a shaking liquid. This shaking breaks the lump into single cells. We then collect these single cells to grow them further. These cultured cells can make special chemicals that plants don't use for growing, but which are useful for us, like medicines.

🎯 Exam Tip: When describing cell suspension culture, emphasize the transition from callus to liquid medium and the importance of agitation. Also, link it to the practical application of secondary metabolite production.

 

Question 14. What do you mean Embryoids? Write its application.
Answer: Embryoids, also known as somatic embryoids, are structures that look like embryos but are formed from somatic (non-reproductive) cells, often from callus tissue, rather than from a zygote. Somatic embryogenesis is the process where these embryos form directly from callus tissue or from in vitro cells that differentiate into pre-embryonic cells.
**Applications:**
1. Somatic embryogenesis can produce many potential plantlets, which can then be grown into full plants after a hardening period.
2. Somatic embryoids are used to create synthetic seeds, which are artificial seeds that contain an embryoid.
3. This process has been observed in many important plants like Allium sativum (garlic), Hordeum vulgare (barley), Oryza sativa (rice), and Zea mays (corn), showing its wide applicability in various plant species.
In simple words: Embryoids are like tiny plant embryos made from regular plant cells, not from seeds. They can grow into full plants. We use them to make many new plants quickly, create artificial seeds, and this method works for many different types of plants.

🎯 Exam Tip: Clearly define embryoids as somatic structures mimicking zygotic embryos. For applications, focus on mass propagation, synthetic seed production, and conservation.

 

Question 15. Give examples of micropropagation performed in plants.
Answer: Micropropagation, which is the rapid multiplication of plants in vitro, is successfully used for many plant species. Some common examples include:
1. Pineapple
2. Banana
3. Strawberry
4. Potato
These plants benefit from micropropagation due to faster multiplication rates and production of disease-free plantlets.
In simple words: We can make many copies of certain plants using micropropagation. Good examples are pineapple, banana, strawberry, and potato plants.

🎯 Exam Tip: When listing examples, choose widely recognized crops that have benefited significantly from micropropagation techniques for commercial production.

 

Question 16. Explain the basic concepts involved in plant tissue culture.
Answer: The basic concepts that are very important in plant tissue culture are totipotency, differentiation, and redifferentiation.
1. **Totipotency:** This is the special ability of any living plant cell. When grown in a suitable nutrient medium in a lab, it has the genetic power to grow into a complete, new individual plant. This ability is unique to plant cells.
2. **Differentiation:** This is the process where plant cells change biochemically and structurally. These changes make the cells specialize to perform specific jobs, like becoming root cells, stem cells, or leaf cells, forming different tissues and organs.
3. **Redifferentiation:** This is when cells that have already specialized (differentiated) change again into another type of cell. For example, if callus cells gain the ability to form a whole plant in a nutrient medium, this phenomenon is called redifferentiation.
4. **Dedifferentiation:** This is the process where mature, specialized cells revert to a meristematic (undifferentiated, actively dividing) state, which then leads to the formation of callus. Both redifferentiation and dedifferentiation show the inherent flexibility of plant cells.
In simple words: Plant tissue culture works because plant cells have special abilities. Totipotency means one cell can become a whole plant. Differentiation is when cells change to do different jobs. Dedifferentiation is when special cells go back to being simple growing cells, like forming a lump called callus. Redifferentiation is when those simple cells then change again to form new plant parts.

🎯 Exam Tip: Thoroughly explain each term with clear, simple definitions. Highlighting the interrelation between differentiation, dedifferentiation, and redifferentiation is important.

 

Question 17. Based on the material used, how will you classify culture technology? Explain it.
Answer: Based on the type of explant (plant material) used, plant tissue culture technology can be classified into several types:
1. **The culture of embryos:** This involves culturing very young embryos, often to rescue embryos from crosses that would otherwise fail. This allows for the development of interspecific and intergeneric hybrids.
• It can also include anther culture and ovule culture for specialized purposes.
• Roots and shoots can also be cultured separately from the whole plant.
2. **Meristem culture:** This is the culture of meristematic tissue (the actively growing tips of shoots or roots) on a suitable culture medium. It is primarily used to produce virus-free plants because meristems are often free of viruses even in infected parent plants.
3. **Protoplast culture:** This involves culturing plant cells from which the cell wall has been removed, leaving only the cell membrane. These "naked" cells are called protoplasts. They are used to create somatic hybrids by fusing protoplasts from different plants, which can then regenerate into whole plants.
4. **Cell culture:** This involves the formation of a cell suspension from callus tissue. The cells are separated from the callus and grown as individual cells or small aggregates in a liquid medium. This technique is often used for the production of secondary metabolites or for genetic transformation studies.
In simple words: We can classify plant culture methods by what plant part we start with. Embryo culture grows tiny baby plants. Meristem culture grows the plant's growing tips, often to get rid of viruses. Protoplast culture grows plant cells without their hard outer wall. Cell culture grows single plant cells in a liquid.

🎯 Exam Tip: For classification questions, list the types clearly and provide a brief explanation for each, focusing on the specific material used and the primary objective of that culture type.

 

Question 18. Give an account on Cryopreservation. The parts such as,
Answer: Cryopreservation, also called cryo-conservation, is a method used to preserve various biological materials like protoplasts, cells, tissues, organelles, organs, and enzymes. This is done by cooling them to an extremely low temperature of -196°C using liquid nitrogen. At this very low temperature, all enzymatic and chemical activities within the biological material completely stop, effectively preserving the material in a dormant state. This deep freezing maintains the viability of cells for very long periods.
Later, these preserved materials can be carefully warmed to room temperature and reactivated for experimental work. To protect the cells and tissues from damage during the freezing process, protective agents called cryoprotectants are added before cryopreservation. Examples of cryoprotectants include dimethyl sulphoxide, glycerol, or sucrose.
In simple words: Cryopreservation is a way to save plant cells, tissues, or organs for a long time by freezing them in liquid nitrogen at a super cold temperature, -196°C. This stops all life processes. We add special chemicals called cryoprotectants to protect them from damage during freezing.

🎯 Exam Tip: Key points to include are the temperature (-196°C), the use of liquid nitrogen, the cessation of metabolic activity, and the role of cryoprotectants in preventing cell damage.

 

Question 19. What do you know about Germplasm conservation? Describe it. Definition
Answer: Germplasm conservation is the process of preserving living genetic resources, such as pollen, seeds, or plant tissue materials, in viable conditions for future use. This is done for various purposes, including hybridization, crop improvement research, and maintaining genetic diversity. Pollen banks and seed banks are common examples of germplasm conservation centers.
**Purpose:**
• To maintain the ability of plants to grow and reproduce (viability and fertility) for future use.
• To keep gene banks and DNA banks of important plants, ensuring their genetic material is available. This helps in securing food supplies for the future.
In simple words: Germplasm conservation means saving living plant genetic material like seeds, pollen, or tissues so we can use them later. This helps us keep different types of plants for research, growing new crops, and making sure we have enough food in the future.

🎯 Exam Tip: Emphasize the long-term storage of genetic material and its importance for biodiversity, crop breeding, and food security. Mentioning pollen banks and seed banks is a good way to illustrate the concept.

 

Question 20. Write the protocol for artificial seed preparation
Answer: The protocol for artificial seed preparation involves several steps to create synthetic seeds from plant material, which can then be grown into plantlets. The process usually follows these stages:
1. **Establishment of callus tissue:** First, a mass of undifferentiated plant cells (callus) is grown from an explant.
2. **Induction of somatic embryogenesis:** The callus is then prompted to form somatic embryos, which are plant embryos developed from non-sexual cells.
3. **Maturation of somatic embryos:** These somatic embryos are allowed to grow and mature to a stage where they are ready for encapsulation.
4. **Encapsulation of somatic embryos:** The mature somatic embryos are individually coated or encapsulated, typically using agrose or sodium alginate gel. This coating protects the embryo and provides nutrients.
5. **Test for embryoid to plant conversion:** The encapsulated embryoids are tested to ensure they can successfully develop into plantlets.
6. **Greenhouse & field planting:** The plantlets that develop from these artificial seeds are then moved to a greenhouse or a hardening chamber for a period of acclimatization (hardening) to adjust to normal environmental conditions before being planted in the field.
In simple words: To make artificial seeds, we first grow a lump of plant cells. Then, we make these cells turn into tiny plant embryos. These little embryos are then covered in a special gel, like a coating. After checking if they can grow, these coated embryos are moved to a greenhouse to get used to the outside world before planting them in the ground.

🎯 Exam Tip: Clearly outline the sequential steps from callus formation to field planting. Highlight encapsulation as the defining step for "artificial seed" and the importance of hardening.

 

12th Bio Botany Guide Plant Tissue Culture Additional Important Questions and Answers

 

I. Choose the correct answer

 

Question 1. Invitro means.
(a) In a test tube.
(c) inside the cell
(d) in a laboratory
Answer: (a) In a test tube
In simple words: "In vitro" means doing experiments or growing things in a controlled environment outside a living body, like in a test tube or a lab dish.

🎯 Exam Tip: "In vitro" literally translates to "in glass," commonly referring to experiments conducted in test tubes or other laboratory glassware.

 

Question 2. The concept of Totipotency was proposed by.
(a) Hildbrandt
(b) Haberlandt
(c) Chilton
(d) Takebe et-al
Answer: (b) Haberlandt
In simple words: The idea that a single plant cell has the full power to grow into a whole plant was first suggested by a scientist named Haberlandt.

🎯 Exam Tip: Remembering key scientists and their contributions, like Haberlandt's concept of totipotency, is important for historical context in biotechnology.

 

Question 3. The scientist developed root cultures, used Knop's solution along with 3 vitamins is.
(a) Murashige & Skoog
(b) P.R. White
(c) Kanta et-al
(d) E.C. Steward
Answer: (b) P.R. White
In simple words: P.R. White was the scientist who figured out how to grow plant roots in a lab using a special liquid food mix called Knop's solution, along with three important vitamins.

🎯 Exam Tip: Associate P.R. White with pioneering work in root cultures and the use of Knop's solution with vitamins for plant tissue growth.

 

Question 4. Virus free Dahlia and Potato plants are produced by.
(b) Martin
(c) Morel & Martin
(d) E.C steward
Answer: (c) Morel & Martin
In simple words: Scientists Morel and Martin were key in finding a way to grow Dahlia and Potato plants that are completely free from viruses, using special lab techniques.

🎯 Exam Tip: Remember Morel & Martin for their significant contribution to producing virus-free plants, particularly potato and dahlia, through tissue culture.

 

Question 5. The Indian scientists developed in vitro production of haploid embryos from
(a) ovule of Nicotiana
(b) anthers of Datura
(c) gametes of Dahlia
(d) Zygote of Carrot
Answer: (b) anthers of Datura
In simple words: Indian scientists successfully grew haploid embryos (embryos with half the normal number of chromosomes) in the lab. They achieved this by using the anthers (part of the flower) from the Datura plant.

🎯 Exam Tip: Recognize anther culture as a method for producing haploid plants, which is valuable in breeding programs for obtaining homozygous lines faster.

 

Question 6. Melchers & Co workers produced
(a) Somatic hybrid of Nicotiana species
(b) Intergeneric hybrid between potato & tomato
(c) Interspecific hybrid of Nicotiana glauca and Nicotiana longs dorffii
(d) test tube fertilization in flowering plants
Answer: (b) Intergeneric hybrid between potato & tomato
In simple words: Melchers and his team created a new kind of plant by joining cells from two different plant types: potato and tomato. This new plant combined features from both.

🎯 Exam Tip: The creation of intergeneric hybrids like "pomato" (potato + tomato) by Melchers highlights the power of protoplast fusion in overcoming natural breeding barriers.

 

Question 7. The growth hormones added in MS – medium are
(a) Auxin & Gibberellins
(c) Gibberelline & cytokinin
(d) Auxin & ABA
Answer: (b) IAA & Kinetin
In simple words: In the common MS growth liquid for plants, two key hormones are added: IAA (a type of auxin) and Kinetin (a type of cytokinin). These help the plant cells grow and develop.

🎯 Exam Tip: Always remember that MS medium typically includes a balance of auxins (like IAA) and cytokinins (like Kinetin) to promote cell division and differentiation.

 

Question 9. Which one of the following is a correct set?
(a) Vincristine Cinchona officinalis Anti carcinogen
(b) Capsacin catharanthus roseus - Antimalarial
(c) Digoxin Digitalis purpuria Cardiac tonic
(d) Codeine Capsicum annum Analgesic
Answer: (c) Digoxin Digitalis purpuria Cardiac tonic
In simple words: Among the options given, Digoxin from Digitalis purpuria is correctly matched as a cardiac tonic. It helps to strengthen the heart's pumping action.

🎯 Exam Tip: When matching plant sources with their medicinal uses, pay close attention to specific names and their functions. Misidentifying the plant or its use is a common mistake.

 

Question 10. Germ plasm conservation does not include
(a) DNA bank
(b) Seed bank
(c) SWISS bank
Answer: (c) SWISS bank
In simple words: Germplasm conservation is about saving genetic resources like DNA or seeds. A "SWISS bank" is a financial institution and is not part of biological conservation efforts.

🎯 Exam Tip: Understand the purpose of germplasm conservation and list the common methods used, such as gene banks and seed banks, to easily identify irrelevant options.

 

Question 11. This is not of the strategies used to make cell suspension
(a) biotrans formation
(b) elicitation
(c) immobilization
(d) filtration
Answer: (d) filtration
In simple words: Biotransformation, elicitation, and immobilization are strategies to make cell suspension cultures work better. Filtration is a way to separate substances, not a strategy for enhancing the culture itself.

🎯 Exam Tip: Differentiate between techniques that enhance a cell culture process and those that are general laboratory procedures. Filtration is a separation technique, not a strategy for making cell suspensions.

 

Question 12. Choose the odd man out with regard to protoplasmic fusion
(a) somatic hybridization
(b) Protoplasmic fusion
(c) Embryoids
(d) Polyethylene Glycol
Answer: (c) Embryoids
In simple words: Somatic hybridization, protoplasmic fusion, and polyethylene glycol are all related to combining protoplasts. Embryoids are plant structures that develop from somatic cells, which is a different outcome, not a technique used for fusion itself.

🎯 Exam Tip: Understand the steps and components involved in protoplast fusion. Identify terms that describe the actual fusion process or agents, as opposed to the resulting structures or a different tissue culture method.

 

Question 13. This is not a technique in PTC?
(a) organ culture
(b) Meristem culture
(c) Cell culture
(d) M.S. culture
Answer: (d) M.S. culture
In simple words: Organ, meristem, and cell cultures are types of plant tissue culture (PTC) techniques. "M.S. culture" refers to Murashige and Skoog medium, which is a specific nutrient medium used in PTC, not a technique itself.

🎯 Exam Tip: Distinguish between types of culture techniques (like organ or cell culture) and specific ingredients or media used in those cultures (like MS medium). Understanding this difference is key.

 

Question 14. Which one of the following is the correct steps in the direct embryogenesis?
(a) Callus \( \downarrow \) Root induction \( \downarrow \) Plantlets \( \downarrow \) Hardening \( \downarrow \) Transfer to field
(b) Explant \( \downarrow \) Embryoids \( \downarrow \) Plantlets \( \downarrow \) Hardening \( \downarrow \) Transfer to field
(c) Callus \( \downarrow \) Multiple shoot induction \( \downarrow \) Root induction \( \downarrow \) Plantlets \( \downarrow \) Hardening \( \downarrow \) Transfer to field
(d) Explant \( \downarrow \) stem \( \downarrow \) Node \( \downarrow \) Multiple shoot induction \( \downarrow \) Root induction \( \downarrow \) Plantlets \( \downarrow \) Hardening \( \downarrow \) Transfer to field
Answer: (b) Explant \( \downarrow \) Embryoids \( \downarrow \) Plantlets \( \downarrow \) Hardening \( \downarrow \) Transfer to field
In simple words: Direct embryogenesis starts from an explant, which directly forms embryoids. These then grow into plantlets, are hardened, and finally moved to the field. This process avoids the callus stage.

🎯 Exam Tip: Memorize the distinct steps for both direct and indirect embryogenesis. Direct embryogenesis bypasses the callus stage, which is a key differentiator.

 

Question 15. Protoplasts are transferred to sucrose solution to
(a) retain osmotic pressure
(b) retain viability
(c) restore solubility
(d) sterilize the protoplast
Answer: (b) retain viability
In simple words: Protoplasts are delicate cells without a cell wall. Transferring them to a sucrose solution helps them stay alive and functional by maintaining their water balance and preventing damage.

🎯 Exam Tip: Always remember that protoplasts are osmotically sensitive. Sucrose solution acts as an osmoticum to prevent them from bursting or shrinking, thus retaining their viability.

 

Question 16. Plants those can'not be subjected to hybridization technique can be raised by?
(a) somatic embryogenesis
(b) PTC
(c) somatic hybridization
Answer: (c) somatic hybridization
In simple words: Somatic hybridization is a technique that combines genetic material from different plant cells (protoplasts) to create new hybrid plants, especially useful when traditional breeding methods are difficult. It allows us to create new types of plants that would otherwise not be possible.

🎯 Exam Tip: Focus on the specific applications of each technique. Somatic hybridization is particularly valuable for species that cannot be crossed sexually or are infertile.

 

Question 17. Indole alkaloids used as bio medicine is got from
(a) phyllanthus amaras
(b) Acalypha indica
(c) Catharanthus roseue
(d) Avena sativa
Answer: (c) Catharanthus roseue
In simple words: Indole alkaloids, which are important in medicine, come from the plant Catharanthus roseus. This plant is a well-known source of valuable compounds.

🎯 Exam Tip: Memorize the specific plant sources for key medicinal compounds. This often appears as a direct recall question in exams.

 

Question 18. Virus is free in
(a) cell culture
(b) protoplasm culture
(c) Apical meristem culture
(d) cambial culture
Answer: (c) Apical meristem culture
In simple words: The tip of a plant shoot, called the apical meristem, is usually free from viruses, even if the rest of the plant is infected. Growing new plants from this part helps create virus-free offspring.

🎯 Exam Tip: Understand why meristem culture is effective for virus elimination: the meristematic tissue divides rapidly, often faster than the virus can replicate and spread into its cells.

 

Question 19. From the following secondary metabolites which one is used as cardioc tonic
(a) capsaicin
(b) Quinine
(c) Codeine
(d) Digoxin
Answer: (d) Digoxin
In simple words: Digoxin is a medicine that helps the heart work better, making it a cardiac tonic. It is obtained from certain plants.

🎯 Exam Tip: Be able to link important secondary metabolites with their primary medicinal uses. Digoxin is a classic example of a cardiac drug from plants.

II. Match the following

 

Question 20.
Column A
a Artificial seeds
b Cybrid
c Virus free Potato
d Cosmetics / Pharmaceuticals
e encapsulated embryoids
Column B
1 Protoplasmic Fusion
2 Plant tissue culture
3 Sec. metabolite
4 Artificial / synseeds
5 Meristmculture
(A) a-2, b-1, c-5, d-3, e-4
(B) a-1, b-2, c-3, d-4, e-5
(C) a-5, b-4, c-3, d-2, e-1
(D) a-4, b-3, c-2, d-1, e-5
Answer: (A) a-2, b-1, c-5, d-3, e-4
In simple words: The correct matches are: Artificial seeds with Plant tissue culture, Cybrid with Protoplasmic Fusion, Virus-free Potato with Meristem culture, Cosmetics/Pharmaceuticals with Secondary metabolite, and encapsulated embryoids with Artificial/synseeds. Each item connects to a specific concept or application in biotechnology.

🎯 Exam Tip: For matching questions, break down each pair. Artificial seeds are produced via plant tissue culture. Cybrids result from protoplasmic fusion. Virus-free plants are grown using meristem culture. Secondary metabolites are used in cosmetics. Encapsulated embryoids are essentially artificial seeds.

 

Question 21.
Column A
a. Codeine
b. Quinine
c. Vincristine
d. Digoxin
e. Capsaicin
Column B
1. Cardiac tonic
2. Treatment of Rheumatic pain
3. Antimalaria drug
4. Analgesic
5. Anti carcinogenic
(A) a -1, b – 2, c-3, d-4, e-5
(B) a – 4, b-3, c-5, d-1, e-2
(C) a – 5, b – 4, c-3, d-2, e-1
(D) a – 3, b-1 c-2, d-5, e-4 .
Answer: (B) a – 4, b-3, c-5, d-1, e-2
In simple words: Codeine is an analgesic (pain reliever). Quinine fights malaria. Vincristine is used against cancer. Digoxin is a cardiac tonic for the heart. Capsaicin helps with rheumatic pain.

🎯 Exam Tip: Knowing the specific medicinal uses of various secondary metabolites is crucial. Create flashcards to remember which compound is used for what purpose.

 

Question 22.
Column A
a High standard of homogeneity
b. Conservation of plant biodiversity
c. Conservation resources of germplasm
d. Liquid nitrogen
Column B
1. encapsulated seeds
2. cryopreservation
3. micro-propagation
4. Pollen banks/seed banks
(A) a-4, b-3, c-2, d-1
(B) a-2, b-4, c-1, d-3
(C) a-3, b-1, c-4, d-2
(D) a-1, b-2, c-3, d-4
Answer: (C) a-3, b-1, c-4, d-2
In simple words: High standard of homogeneity is achieved through micro-propagation. Encapsulated seeds help conserve plant biodiversity. Germplasm resources are conserved in pollen and seed banks. Liquid nitrogen is used in cryopreservation.

🎯 Exam Tip: Connect the concepts to their practical applications. Micro-propagation ensures uniform plants, encapsulated seeds aid biodiversity, germplasm banks store genetic material, and liquid nitrogen is central to cryopreservation.

III. Choose the incorrect Statement

 

Question 23.
(a) The plant material used in tissue culture should be surface sterilized
(b) Callus is a mass of unorganized growth of plant cells or tissues in invivo culture
(c) The fusion product of protoplasts without a nucleus of different cells is called cybrid
(d) Bioreactors are used for the production of secondary metabolites in a commercial way
Answer: (b) Callus is a mass of unorganized growth of plant cells or tissues in invivo culture
In simple words: The statement is incorrect because callus refers to unorganized cell growth in *in vitro* (laboratory) culture, not *in vivo* (inside a living organism). All other statements are correct facts about tissue culture.

🎯 Exam Tip: Pay close attention to terms like "in vitro" and "in vivo" in biotechnology questions. They define where the process takes place and are critical for correctness.

 

Question 24. Which one of the following statements is true regarding IPR?
(a) The discoverer has the full rights on his / her property
(b) IPR – includes only the process of the product, not trade secrets.
(c) IPR is not protected by laws formed by the country.
(d) The discoverer can use his discovery for his own company but can not sell it to others.
Answer: (a) The discoverer has the full rights on his / her property
In simple words: Intellectual Property Rights (IPR) give the creator complete control over their inventions and works. This means they own it fully and can decide how it is used or sold.

🎯 Exam Tip: Understand the fundamental principle of IPR: it grants exclusive rights to the creator or owner over their intellectual creations, allowing them to benefit from and control their work.

IV. Choose the correct Statement

 

Question 25.
(a) The HGP was founded in 2010 as an integral part of ELSI
(b) GEAC is an apex body under the UNO
(c) GMOs-GEMs & Trans genie plants approval are not coming under the scanning of GEAC
(d) The release of genetically engineered organisms and products into the environment need at least three levels of field trials such as BRL -1, BRL II & BRL III
Answer: (d) The release of genetically engineered organisms and products into the environment need at least three levels of field trials such as BRL -1, BRL II & BRL III
In simple words: Before genetically engineered organisms can be released into nature, they must pass through three different safety trial levels. This ensures they are safe for the environment and people.

🎯 Exam Tip: Be aware of the regulatory processes for genetically engineered organisms, especially the multi-level trial requirements for environmental release. This highlights the focus on biosafety.

 

Question 26.
(a) 'Takepe' regenerated tobacco plants from isolated mesophyll protoplasts.
(b) Morel & Martin formulated Bioethics.
(c) The photoperiod needs for Tissue culture is 12-18 hours of light.
(d) The PH medium for Tissue culture should be below 5
Answer: (a) 'Takepe' regenerated tobacco plants from isolated mesophyll protoplasts
In simple words: Takebe was the first to successfully grow whole tobacco plants from single leaf cells (mesophyll protoplasts). This was a major step forward in plant biotechnology.

🎯 Exam Tip: Familiarize yourself with key historical milestones and the scientists associated with them in plant tissue culture. Specific achievements like Takebe's work with tobacco are important.

V. In each of the following questions, two statements are given – one as Assertion (A) and the other one is Reason (R) Mark the correct answer as

 

Question 28. Assertion: A major advantage of tissue culture is protoplast fusion. Reason: It produces a genetically uniform population.
Answer: (c) It A is true but 'R' is false
In simple words: Protoplast fusion is indeed a big benefit of tissue culture. However, the reason given is wrong because protoplast fusion creates new genetic combinations, not a uniform population. Micropropagation leads to a uniform population.

🎯 Exam Tip: Carefully evaluate both the Assertion and the Reason independently before checking their relationship. Protoplast fusion introduces variation, while micropropagation ensures genetic uniformity.

 

Question 29. Assertion(A): The explants are sterilized by mercuric chloride Reason(R): Sterilization prevents the growth of other microorganisms in the Culture medium
Answer: (b) (A) wrong: (R) correct
In simple words: While sterilization is vital to stop microbes from growing in the culture medium (Reason is correct), explants are usually surface sterilized using agents like sodium hypochlorite or ethanol, not typically mercuric chloride (Assertion is wrong).

🎯 Exam Tip: Know the common sterilizing agents used in tissue culture and their applications. Mercuric chloride is highly toxic and less commonly used for explant sterilization compared to others.

VI. Two Marks

 

Question 1. What are the contributions of Haberlandt to PTC?
Answer: Haberlandt made significant contributions to Plant Tissue Culture (PTC). Firstly, he successfully performed *in vitro* (in laboratory) culture of plant cells. Secondly, he used Knop's salt solution along with glucose and peptone as a culture medium. Most importantly, he introduced the concept of totipotency, which is the idea that a single plant cell can grow into a whole plant. This was a foundational concept for plant tissue culture.
In simple words: Haberlandt was key to early plant tissue culture. He grew plant cells in a lab using a special liquid and introduced the idea that one plant cell can become a whole plant.

🎯 Exam Tip: When discussing historical contributions, always mention the key experiment or concept introduced by the scientist. Haberlandt's concept of totipotency is a critical point.

 

Question 2. What is the special contribution of Murashige and Skoog?
Answer: Murashige and Skoog's special contribution was formulating a widely used tissue culture medium, known as MS medium, in 1962. This medium became a landmark in Plant Tissue Culture (PTC) because it is the most frequently used culture medium for almost all types of tissue culture work. Its balanced composition of nutrients supports the growth of many different plant tissues effectively.
In simple words: Murashige and Skoog created the MS medium, a very popular nutrient mix for growing plant tissues in the lab. This made it much easier to do tissue culture work.

🎯 Exam Tip: Murashige and Skoog are famous for the MS medium. Highlight its widespread use and importance in supporting various tissue culture experiments.

 

Question 3. Who developed first interspecific somatic hybrid?
Answer: The first interspecific somatic hybrid was developed by Carlson and his co-workers in 1971. They achieved this by fusing protoplasts (plant cells without cell walls) from two different species, *Nicotiana glauca* and *Nicotiana longsdorffii*. This breakthrough showed that it was possible to create new hybrid plants by combining cells from different species in the lab, overcoming natural barriers.
In simple words: Carlson and his team made the first hybrid plant by joining cells from two different tobacco species in the lab in 1971.

🎯 Exam Tip: Remember the name Carlson and the year 1971 for the first interspecific somatic hybrid. Knowing the specific plant species involved (*Nicotiana glauca* and *Nicotiana longsdorffii*) adds detail to your answer.

 

Question 4. Define Totipotency?
Answer: Totipotency is the unique property of living plant cells to develop into a complete individual plant when grown in a suitable nutrient medium. This means even a single plant cell holds all the genetic information needed to regenerate into a full plant, including roots, stems, and leaves. It is a fundamental concept in plant tissue culture. This inherent genetic potential is what makes plant tissue culture possible. It is one of the basic concepts used in tissue culture.
In simple words: Totipotency means that any living plant cell has the full power to grow into a whole new plant, given the right conditions.

🎯 Exam Tip: When defining totipotency, emphasize "living plant cells," "genetic potential," and "complete individual plant." It's the core idea enabling regeneration from a single cell.

 

Question 5. What are the components of Knop's solution?
Answer: Knop's solution, a nutrient medium, primarily contains various salts dissolved in a sucrose solution, along with deionized water. The key components are:
I. Various Salts dissolved in Sucrose solution:
* Calcium Chloride: 3.0 gm
* Potassium Nitrate: 1.0 gm
* Magnesium Sulphate: 1.0 gm
* Dibasic Potassium Phosphate: 1.0 gm
II. Sucrose: 50 gm (optimal, acts as a carbon source)
III. Deionized Water: 1000ml (to dissolve all ingredients).
This blend provides essential nutrients for plant cell growth.
In simple words: Knop's solution is a mix of important salts like calcium chloride, potassium nitrate, magnesium sulphate, and phosphate, along with sugar (sucrose), all dissolved in pure water. It feeds the plant cells.

🎯 Exam Tip: Remember the major salt components and their approximate quantities (if specified). Also, highlight the role of sucrose as an energy source and deionized water as the solvent.

 

Question 6. Distinguish between Redifferentiation and Dedifferentiation.
Answer:
**Redifferentiation:** This is when a differentiated cell (a specialized cell) further changes into another type of specialized cell. For example, in tissue culture, if callus cells (which are unspecialized) develop into organized structures like shoots and roots (embryoids), this process is called redifferentiation. It means cells gain a new, more specific function.
**Dedifferentiation:** This is the process where mature, specialized cells go back to a less specialized, meristematic state. This leads to the formation of callus tissue, which is a mass of unorganized cells. It's like a specialized cell "forgetting" its job and becoming a basic, versatile cell again.
In simple words: Dedifferentiation is when a special cell becomes simple again, like forming callus. Redifferentiation is when those simple cells then become special again, like making shoots or roots.

🎯 Exam Tip: The key difference is the direction of change: Dedifferentiation means specialized to unspecialized (forming callus), while Redifferentiation means unspecialized to re-specialized (forming organs like shoots/roots).

 

Question 8. What is Agar?
Answer: Agar is a mucilaginous polysaccharide, meaning it's a jelly-like carbohydrate, that is obtained from certain marine algae, particularly red seaweeds like *Gelidium*, *Gracilaria*, and *Gelidiella*. In plant tissue culture, agar is widely used as a solidifying agent. It helps to turn liquid nutrient media into a semi-solid gel, providing a stable surface for plant cell and tissue growth. This makes it easier to handle cultures and provides support for growing tissues.
In simple words: Agar is a jelly-like substance from seaweeds. It is used to make liquid growing solutions thick and solid for plant tissue culture, helping the plants to grow on a firm base.

🎯 Exam Tip: Remember agar as a seaweed-derived polysaccharide used primarily for solidifying culture media, not as a nutrient itself, but providing physical support.

 

Question 9. Notes on Autoclave.
Answer: An autoclave is a specialized device essential for sterilization in tissue culture, using wet steam under high pressure. This method, known as wet steam sterilization, is highly effective. Autoclaving is typically done at 15 psi (pounds per square inch) and 121°C for 15-30 minutes, which kills all microorganisms, including spores. Importantly, all glassware, forceps, scalpels, and other tools used in tissue culture are sterilized in an autoclave to maintain an aseptic (contamination-free) environment. This ensures that only the desired plant cells grow.
In simple words: An autoclave is a machine that uses hot, high-pressure steam (121°C at 15 psi for 15-30 minutes) to kill all germs. It sterilizes all the tools and glassware used in plant tissue culture to keep things clean.

🎯 Exam Tip: Key details for autoclaving are the temperature (121°C), pressure (15 psi), and time (15-30 minutes). Emphasize its role in achieving complete sterilization for aseptic conditions.

 

Question 10. What are the minor nutrients added in MS medium?
Answer: In addition to major nutrients, MS (Murashige and Skoog) medium also includes minor nutrients, or micronutrients, which are essential for plant growth in smaller quantities. These typically include:
* Sodium molybdate
* Cupric sulphate
* Cobaltous chloride
* Zinc sulphate
* Boric acid
* Manganese sulphate
* Potassium iodide
These elements act as cofactors for various enzyme activities, playing vital roles in plant metabolism and development.
In simple words: MS medium has small amounts of important nutrients like sodium molybdate and cupric sulphate. These tiny additions are still very important for the plants to grow well.

🎯 Exam Tip: Remember that both macro- and micronutrients are essential. While macronutrients are needed in larger amounts, micronutrients, though in small quantities, are equally crucial for specific metabolic functions. List a few key examples.

 

Question 11. Why do we subject plantlets to hardening?
Answer: Plantlets grown in *in vitro* (laboratory) conditions are very delicate and are used to a controlled environment with specific light, temperature, and nutrient levels. Hardening is a crucial process where these plantlets are gradually adapted to the harsher, natural environmental conditions found outside the lab. This slow adaptation involves exposing them to diffused light, varying temperatures, and eventually soil, preparing them to survive and grow well in the open field. This helps them develop stronger root systems and protective cuticles.
In simple words: Lab-grown plantlets are fragile. Hardening slowly gets them used to normal light, temperature, and soil outside the lab, making them strong enough to survive in nature.

🎯 Exam Tip: Explain hardening as a gradual acclimatization process. Focus on the transition from artificial (lab) to natural (field) conditions and the physiological changes it induces for survival.

 

Question 12. What is cybrid?
Answer: A cybrid (cytoplasmic hybrid) is a unique fusion product of two different protoplasts (plant cells without cell walls) where the nucleus from one of the parent protoplasts is lost or eliminated. This means the resulting cell has the nucleus from only one parent, but it contains cytoplasm, including organelles like mitochondria and chloroplasts, from both parent cells. Cybrids are useful for transferring cytoplasmic traits, such as cytoplasmic male sterility or herbicide resistance, from one plant to another.
In simple words: A cybrid is a special new cell made by joining two plant cells. It gets its main control center (nucleus) from one parent, but takes the other parts (cytoplasm and its organelles) from both parents.

🎯 Exam Tip: The key characteristic of a cybrid is the presence of a nucleus from one parent and cytoplasm from both. This distinguishes it from a true somatic hybrid which has nuclei from both parents.

 

Question 13. What are the various components of MS- Medium?
Answer: The MS (Murashige and Skoog) medium is a widely used plant tissue culture medium, composed of several key components to support optimal plant cell growth. These include:
* **Macronutrients:** These are elements required in larger quantities, such as nitrogen, potassium, calcium, magnesium, phosphorus, and sulfur.
* **Micronutrients/Minor nutrients:** These are trace elements needed in smaller amounts, like iron, manganese, zinc, boron, copper, and molybdenum.
* **Vitamins:** Organic compounds like thiamine, nicotinic acid, and pyridoxine, which act as cofactors for enzyme reactions.
* **Growth Hormones:** Plant growth regulators such as auxins, cytokinins, and sometimes gibberellins, added in specific measurements to control cell division and differentiation.
* **Solidifying Agent:** Agar is typically added to solidify the medium, providing a stable surface for cell and tissue growth.
* **Carbon Source:** Sucrose is commonly included as a readily available energy source.
In simple words: MS medium has big nutrients (like nitrogen), tiny nutrients (like iron), vitamins, plant growth hormones, and sugar for energy. Agar is also added to make it solid so plants can grow on it.

🎯 Exam Tip: Categorize the components of MS medium (macro/micronutrients, vitamins, hormones, carbon source, gelling agent) and provide examples for each. This shows a comprehensive understanding.

 

Question 14. How to remove the cell wall of a plant cell.
Answer: To remove the cell wall of a plant cell and obtain a protoplast, a specific enzymatic digestion method is used. The chosen leaf tissue is first immersed in a solution containing:
* **0.5% Macerozyme:** This enzyme helps to separate individual cells by digesting the middle lamella, which is the layer between adjacent plant cells.
* **2% Onozuka cellulose enzyme:** This enzyme is crucial for breaking down the cellulose in the plant cell wall itself.
These enzymes are typically dissolved in a solution of 13% sorbitol or mannitol (osmotic stabilizers) at a pH of 5.4, and the tissue is incubated at 25°C overnight. After this enzymatic treatment and gentle teasing, the protoplasts (cells without walls) are released. To ensure their viability, they are then transferred to a 20% sucrose solution, and finally, they are isolated by centrifugation.
In simple words: To remove a plant cell wall, leaf tissue is put in a special enzyme mix (macerozyme and cellulose enzyme) with sugar alcohols overnight. These enzymes break down the wall, leaving behind bare cells called protoplasts, which are then cleaned.

🎯 Exam Tip: Key points for cell wall removal are the specific enzymes (macerozyme, cellulase), osmotic stabilizers (sorbitol/mannitol), and the incubation conditions (pH, temperature, time). This enzymatic approach creates viable protoplasts.

 

Question 15. What is organogenesis?
Answer: Organogenesis is a process in plant tissue culture where morphological changes in the callus (an unorganized mass of plant cells) lead to the formation of organized structures like shoots, roots, and eventually whole plantlets. This process typically occurs in two main steps. When roots are formed, it's called Rhizogenesis. When shoots are formed, it's called Caulogenesis. By carefully adjusting the balance of plant hormones in the culture medium, scientists can direct the callus to develop either roots or shoots, or both, regenerating a complete plant.
In simple words: Organogenesis is when unformed plant cells in a lab start growing into proper plant parts like roots and shoots. If it makes roots, it's Rhizogenesis; if it makes shoots, it's Caulogenesis.

🎯 Exam Tip: Define organogenesis as the formation of organized structures (shoots/roots) from callus. Clearly distinguish between Rhizogenesis (root formation) and Caulogenesis (shoot formation).

 

Question 16. Distinguish between callus & clone
Answer:
**Callus:** Callus refers to a mass of unorganized, undifferentiated plant cells or tissues that grows *in vitro* (in the laboratory) in a culture medium. It is typically a soft, yellowish-white mass formed when plant cells proliferate without forming specific organs. It is a transitional stage in many plant tissue culture protocols.
**Clone:** A clone refers to a genetically uniform population of plantlets that develops from callus. These plantlets are identical to the parent plant from which the original explant was taken. Clones are formed when callus cells differentiate and develop into organized structures, eventually forming whole plants that are genetic copies. The term "clone" specifically highlights the genetic identicalness.
In simple words: Callus is just a blob of unorganized plant cells grown in the lab. A clone is a group of new, full plants that are exactly identical to the original parent plant, often grown from callus.

🎯 Exam Tip: The key distinction is organization and genetic identity. Callus is unorganized and undifferentiated, while clones are organized, differentiated, and genetically identical copies of the parent plant.

 

Question 19. Give the tabulation of a few secondary metabolites their plant sources.
Answer: Here is a table showing some important secondary metabolites, the plants they come from, and their uses. These compounds play various roles in plant defense and human health.

In simple words: This table shows useful plant chemicals. It tells you which plant makes them and what they are used for, like medicines or pain relief.

🎯 Exam Tip: When tabulating information, always use clear columns and rows. Remember to include the common name of the plant if available, as it can help recall the source.

 

Question 20. Give the IPR - aspects in India
Answer: Intellectual Property Rights (IPR) in India cover different aspects of creations from the mind. These rights ensure that creators can benefit from their inventions and original works. The main aspects include:

• **Trade Secrets:** Confidential information that gives a business a competitive edge.
• **Trademark:** A symbol, design, or phrase legally registered or established by use as representing a company or product.
• **Copyright:** Protects original literary, dramatic, musical, and artistic works.
• **Patent:** A legal right given to an inventor for an invention, allowing them to exclude others from making, using, or selling it for a limited time.
• **Geographical Indication:** Used on products that have a specific geographical origin and possess qualities or a reputation due to that origin.
• **Utility/Model Design:** Protects the ornamental or aesthetic aspect of an article.
• **Plant Breeders' Rights:** Protects the rights of plant breeders over new varieties of plants.

**Other Various Aspects:**
The property mentioned above, derived from discoveries, should not be used by others without legal permission or proper authorization. These rights must be protected by the laws created by a country to ensure fair use and reward for innovation.
In simple words: IPR in India means legal rights for new ideas or creations, like patents for inventions or copyrights for books. It stops others from copying them without asking.

🎯 Exam Tip: For IPR questions, define each aspect clearly. A simple diagram or list of types, like in the source, helps illustrate the scope of IPR.

 

Question 21. Expand the following. PTC, HEPA, RCGM -, GE AC, ELSI, GMO
Answer: Here are the full forms for the given acronyms. Understanding these terms is important for studying biotechnology and related fields.

• **PTC** - Plant Tissue Culture
• **HEPA** - High-Efficiency Particulate Air
• **RCGM** - Review Committee on Genetic Manipulation
• **GEAC** - Genetic Engineering Appraisal Committee
• **ELSI** - Ethical, Legal, and Social Implications
• **GMO** - Genetically Modified Organism
• **GEM** - Genetically Engineered Micro Organism

In simple words: This lists the full names for common shortcuts used in plant science and genetics.

🎯 Exam Tip: Always practice writing out full forms accurately. For longer names, breaking them into parts (like Ethical, Legal, and Social Implications) helps in memorization.

 

Question 22. Name the cryoprotectants used in Cryopreservation
Answer: In cryopreservation, special substances called cryoprotectants are used to protect cells and tissues from damage during freezing. These agents prevent the formation of large ice crystals that can harm biological material. Common cryoprotectants include:

• Dimethyl sulphoxide
• Glycerol
• Sucrose

They help preserve the cells and tissues by reducing the stress caused by very low freezing temperatures. Thus, they are known as cryoprotectants.
In simple words: Cryoprotectants are chemicals like glycerol or sugar that we add to cells before freezing them. They stop the cells from getting damaged by ice.

🎯 Exam Tip: List the cryoprotectants clearly. Adding a brief explanation of *why* they are used (to prevent freezing damage) enhances the answer.

 

Question 23. How is ELSI research funded?
Answer: ELSI (Ethical, Legal, and Social Implications) research typically receives funding from a portion of the Human Genome Project (HGP) budget. In the US, this funding was often allocated from the National Institute of Health (NIH) and the US Department of Energy (DOE). These funds were specifically dedicated to ELSI research.
In simple words: ELSI research gets money from the big project that studies human genes, like from health and energy departments.

🎯 Exam Tip: When answering about funding, identify the source of the funds and the specific projects or institutions involved. Mentioning the HGP is key here.

 

Question 24. What is Biosafety?
Answer: Biosafety is about preventing the large-scale loss of biological integrity. It focuses on keeping both ecology (the natural environment) and human health safe. This involves setting up rules and ways to handle biological materials and research safely, to protect people and the environment from harm.
In simple words: Biosafety means taking steps to protect people and nature from harm when working with living things, especially in labs.

🎯 Exam Tip: A good definition of biosafety should highlight its dual focus: protecting human health and ecological balance from biological risks.

 

Question 25. Differentiate of Organ culture and meristem culture
Answer: Here is how organ culture and meristem culture differ:

• **Organ Culture:** This involves growing whole plant organs, like embryos, anthers (parts of a flower), ovaries, roots, or shoots, in a controlled environment. The goal is often to study organ development or to produce specific compounds.
• **Meristem Culture:** This technique focuses on culturing meristematic tissue (the actively growing tips of plants) from any plant. Meristems are often virus-free, so this method is commonly used to produce healthy plants free of diseases.

Meristem culture is particularly valuable for virus elimination, as meristematic cells usually do not carry viruses.
In simple words: Organ culture grows big parts of a plant like roots or flowers. Meristem culture grows only the tiny growing tips of a plant, often to make new plants that are free from diseases.

🎯 Exam Tip: For differentiation questions, clearly state the main characteristic or purpose of each type of culture. Highlighting the "virus-free" aspect is crucial for meristem culture.

 

VII. Three Marks

 

Question 1. Give the name of few culture media used in PTC & their nature.
Answer: Plant Tissue Culture (PTC) relies on specific nutrient media to support plant cell growth. Here are some commonly used media and their nature:

• **M.S. Nutrient Medium (Murashige & Skoog -1992):** This is one of the most widely used media. It provides carbon sources, various vitamins, and plant hormones essential for growth.
• **B5 - Medium (Gamborg et al. 1968):** Another popular medium, often used for cell suspension cultures and protoplast culture.
• **White Medium (White 1943):** An older medium, typically used for root cultures.
• **Nitsch's Medium (Nitsch & Nitsch 1969):** Frequently used for anther and pollen culture to produce haploid plants.

These media can be prepared as solid, semi-solid, or liquid. A gelling agent like agar is added for solidification to create a firm surface for cell growth.
In simple words: To grow plant cells in a lab, we use special foods called culture media. Examples are MS medium and B5 medium, which have sugar, vitamins, and hormones. We can make them liquid or solid.

🎯 Exam Tip: Name at least three different culture media and briefly mention their key components or a unique application. Remember to state that agar is used for solidifying liquid media.

 

Question 2. Explain the Induction of Callus.
Answer: Callus induction is the process of making plant cells grow into an unorganized mass of cells called a callus. This is a key step in many plant tissue culture techniques. Here are the steps involved:

**Steps for Callus Induction:**

**I) Inoculation:** A sterile piece of plant tissue, called an explant (like a segment of leaf, stem, tuber, or root), is placed onto a sterile nutrient medium, such as MS medium, along with plant growth hormones like auxins.

**II) Incubation:** The prepared medium with the explant is kept in a controlled environment. This usually means incubating it at 25 °C ± 2 °C with a cycle of 12 hours of light and 12 hours of darkness. The precise temperature and light cycle are vital for proper cell growth.

**III) Induction of Callus:** During incubation, the cells from the explant begin to divide rapidly and without a specific pattern. This unorganized growth on the surface of the explant leads to the formation of a callus. A callus is a mass of unorganized plant cells or tissue grown in vitro (in a test tube or lab dish) in a culture medium.
In simple words: Callus induction is when you take a small plant part and put it on special food in a lab. You keep it warm and in certain light. Then, the plant cells start growing into a messy lump called a callus.

🎯 Exam Tip: Explain each step (Inoculation, Incubation, Induction) clearly. Mentioning the explant, nutrient medium, growth hormones, and controlled conditions (temperature, light cycle) are important keywords.

 

Question 3. Write the flow chart of plant Regeneration pathway.
Answer: Plant regeneration involves growing whole plants from explants through either somatic embryogenesis or organogenesis. Below is a description of the flow chart for this process:

**Plant Regeneration Pathway**

**From Explant:**

1. **Explant** (Meristem, Shoot apex, Stem, Leaf, Root)
\( \downarrow \)
**Direct Embryogenesis:**
\( \downarrow \)
**Embryoids**
\( \downarrow \)
**Plantlets**
\( \downarrow \)
**Hardening**
\( \downarrow \)
**Transfer to field**

2. **Explant** (Callus)
\( \downarrow \)
**Indirect Embryogenesis:**
\( \downarrow \)
**Shoot Induction**
\( \downarrow \)
**Root Induction**
\( \downarrow \)
**Plantlets**
\( \downarrow \)
**Hardening**
\( \downarrow \)
**Transfer to field**

3. **Explant** (Stem, Noda, Leaf, Root)
\( \downarrow \)
**Multiple Shoot Induction (Micro-propagation):**
\( \downarrow \)
**Root Induction**
\( \downarrow \)
**Plantlets**
\( \downarrow \)
**Hardening**
\( \downarrow \)
**Transfer to field**

4. **Virus free plantlets**
\( \downarrow \)
**Root Induction**
\( \downarrow \)
**Plantlets**
\( \downarrow \)
**Hardening**
\( \downarrow \)
**Transfer to field**

This pathway shows how a small piece of plant tissue can be grown into a full plant using different tissue culture methods, eventually moving to a natural environment.
In simple words: This is like a recipe for growing new plants from a small piece. You can either grow tiny embryos, make many shoots, or use virus-free parts. In the end, the small plants are made strong and then put into the soil.

🎯 Exam Tip: When describing a flowchart, clearly list each step in sequential order. Use arrows or clear bullet points to show the flow. Group related steps, such as those leading to direct or indirect embryogenesis, for better clarity.

 

Question 4. What are the application of somatic embrogenesis
Answer: Somatic embryogenesis is a powerful plant tissue culture technique with several important applications:

• **Production of Plantlets:** It provides a way to get many potential plantlets from somatic cells. After a hardening period, these plantlets can be successfully grown into mature plants.
• **Synthetic Seeds:** Somatic embryoids can be used to create synthetic seeds. These are artificial seeds that contain an embryoid (a small plant embryo) and a protective coating, allowing for easy handling and storage.
• **Widespread Application:** This technique is now used for many plants, including garlic (Allium sativum), barley (Hordeum vulgare), rice (Oryza sativa), and corn (Zea mays). This shows that it can work for almost any plant species.

This method allows for efficient propagation and genetic improvement of various crops.
In simple words: Somatic embryogenesis helps make many small plants, create fake seeds for storage, and works for many different types of plants like rice and corn.

🎯 Exam Tip: When listing applications, focus on the practical benefits. Highlighting the production of plantlets, synthetic seeds, and its broad applicability across various plant species are key points.

 

Question 4. Explain various steps in Protoplast culture.
Answer: Protoplasts are plant cells that have had their cell walls removed, but still have a cell membrane. The process of protoplast culture involves several key steps:

1. **Isolation of protoplast:**
   • Leaf tissue is first placed in a solution containing 0.5% macerozyme and 2% onozuka cellulose enzymes. These enzymes are dissolved in 13% sorbitol or mannitol at a pH of 5.4.
   • The tissue is then incubated overnight at 25°C.
   • After incubation, the protoplasts are carefully separated by gentle teasing.
   • These isolated protoplasts are then moved to a 20% sucrose solution to help them stay alive.
   • Finally, the protoplasts are separated from cell wall debris by centrifugation.
2. **Fusion of protoplast (Agglutination & Fusion):**
   • Two different protoplasts (A and B) are brought together and made to fuse. This fusion is helped by a fusogenic agent like Poly Ethylene Glycol (PEG) at 25-30% concentration, along with Ca++ ions.
3. **Culture of protoplast:**
   • The health of the protoplasts is checked using fluorescein diacetate before culturing.
   • The protoplasts are then grown in an MS medium, sometimes with small changes. They are cultured as droplets, or plated, or as microdrops.
   • Incubation takes place in continuous light (1000-2000 lux) at 25°C.
   • New cell walls form within 24-48 hours.
   • The first division of new cells happens within 2-7 days of culturing.
4. **Selection of somatic hybrid cells:**
   • When protoplasts from different cells fuse without their nuclei combining, the resulting product is called a cybrid. This process of forming somatic hybrids is also known as somatic hybridization.

In simple words: First, cell walls are removed from plant tissues to get individual cells called protoplasts. These protoplasts are then made to join together (fuse). After fusion, they are grown in a special liquid food, where they form new cell walls and start dividing. Finally, the new combined cells, called somatic hybrids or cybrids, are selected for further use. This method helps create new plant types.

🎯 Exam Tip: Remember the four main stages: isolation, fusion, culture, and selection. Highlighting the specific agents like enzymes for isolation and PEG for fusion will fetch you full marks.

 

Question 5. What is meant by biosafety? Explain.
Answer: Biosafety refers to the set of strict rules and guidelines used in biological laboratories and related industries. It involves applying scientific knowledge, techniques, and special equipment to safely handle biological materials. The main goal is to prevent large-scale loss of:

• Biological integrity
• Ecology
• Human health aspects

Biosafety also aims to reduce human errors and technical failures that could lead to unnecessary risks. Essentially, it ensures that working with biological agents is done without harming people, the environment, or other organisms.In simple words: Biosafety means following strict rules when working with living things in labs to keep everyone and the environment safe. It helps prevent big problems like diseases spreading or harm to nature, making sure we work carefully and correctly.

🎯 Exam Tip: When defining biosafety, emphasize "strict guidelines" and its dual focus on "ecology" and "human health" to show a complete understanding.

 

Question 6. Expand ELSI & What is meant by Bioethics.
Answer: ELSI stands for Ethical, Legal, and Social Implications. Bioethics refers to the study of ethical issues that arise from advancements in biotechnology. Key aspects of Bioethics include:

• **Advancements in biotechnology:** This covers areas like transgenic plants in agriculture, gene therapy in the pharmaceutical industry, and progress in medicine.
• **Controversies:** Biotechnological applications have often led to public debates and concerns, sometimes causing social unease and raising legal issues.
• **Ecological and moral values:** These applications touch upon important principles related to nature and what is considered right or wrong.

Therefore, it is crucial to legally regulate modern biotechnological applications. This ensures that biotechnology is used ethically and safely for the well-being of humanity and all other living organisms on Earth.In simple words: ELSI means looking at the right, legal, and social parts of new science. Bioethics is about deciding what is right and wrong when using new technologies like genetic engineering. It makes sure that new science helps people and nature without causing harm, and that proper laws are in place.

🎯 Exam Tip: Clearly state the full form of ELSI. For Bioethics, focus on the "ethical, legal, and social" challenges and the need for "regulation" in biotechnology.

 

Question 7. Write about Potential risks and consideration for safety aspects.
Answer: When dealing with biological materials and new technologies, there are several potential risks and safety concerns to consider:

• **Pathogenicity:** Living organisms and viruses, whether natural or genetically modified, can cause diseases in humans, animals, and plants. This risk needs careful management.
• **Toxicity of allergy:** Microbial production can sometimes lead to toxic substances or cause allergic reactions. This requires strict checks and safety measures.
• **Antibiotic resistance:** The increasing number of antibiotic-resistant microbes is a major concern. It means that infections become harder to treat.
• **Disposal problem:** Dealing with spent microbial biomass and hazardous chemicals requires proper disposal methods to prevent environmental contamination.
• **Safety aspects:** These include preventing contamination of experiments, avoiding infections, and dealing with potential mutant strains that might arise.
• **Industrial use:** Regulations are needed for the industrial use of microorganisms containing in vitro recombinants to ensure they are handled safely and do not pose risks to the environment or public health.

In simple words: Using new biological methods can have risks like making people or plants sick, causing allergies, or creating stronger germs that resist medicine. We also need to safely throw away waste and make sure new lab-made germs do not escape. All these things must be thought about carefully to keep everyone safe.

🎯 Exam Tip: Listing specific risks like "pathogenicity", "toxicity/allergy", and "antibiotic resistance" shows a comprehensive understanding. Also, mention disposal and general safety protocols.

 

Question 8. List down organizations implementing Bio-safety guidelines.
Answer: Various organizations are responsible for implementing biosafety guidelines to ensure safe practices in biotechnology and research:

• **IBSCs (Institutional Bio-Safety Committees):** These committees monitor research activities at the institutional level, making sure all biosafety rules are followed within a specific lab or institute.
• **RCGM (The Review Committee on Genetic Manipulation):** Functioning under the Department of Biotechnology (DBT), this committee oversees risky research activities in laboratories, especially those involving genetic manipulation.
• **GEAC (Genetic Engineering Approval Committee):** This committee, under the Ministry of Environment and Forest, has the authority to approve the commercial use of Genetically Modified Organisms (GMOs) and to conduct open field trials of transgenic crops. It ensures that GMOs are safe before being released.

These organizations help manage the ethical, legal, and environmental aspects of biotechnology.In simple words: Many groups help make sure science is safe. Institutional Bio-Safety Committees check labs, the Review Committee on Genetic Manipulation watches risky genetic work, and the Genetic Engineering Approval Committee approves new genetically modified plants for use.

🎯 Exam Tip: Remember the full forms and primary functions of each organization. Mentioning their regulatory role in different stages (institutional, research, commercial) is key.