CBSE Class 12 Biology Reproduction in Organisms Worksheet Set A

Read and download free pdf of CBSE Class 12 Biology Reproduction in Organisms Worksheet Set A. Download printable Biology Class 12 Worksheets in pdf format, CBSE Class 12 Biology Chapter 1 Reproduction in Organisms Worksheet has been prepared as per the latest syllabus and exam pattern issued by CBSE, NCERT and KVS. Also download free pdf Biology Class 12 Assignments and practice them daily to get better marks in tests and exams for Class 12. Free chapter wise worksheets with answers have been designed by Class 12 teachers as per latest examination pattern

Chapter 1 Reproduction in Organisms Biology Worksheet for Class 12

Class 12 Biology students should refer to the following printable worksheet in Pdf in Class 12. This test paper with questions and solutions for Class 12 Biology will be very useful for tests and exams and help you to score better marks

Class 12 Biology Chapter 1 Reproduction in Organisms Worksheet Pdf

Very Short Answer

Question. What is clone?
Answer. Clone is used to describe such morphologically and genetically similar individuals.

Question. In organisms what is the mode of reproduction?
Answer. In organisms cell division itself a mode of reproduction.

Question. How single celled organisms reproduce?
Answer. Single-celled organisms reproduce by binary fission

Question. What is life span?
Answer. The period from birth to the natural death of an organism represent its life span

Question. Which reproduction is common among single-celled organisms?
Answer. Asexual reproduction is common among single celled organisms.

 

Short Answer

Question. What do you mean by vegetative propagules?
Answer. The units or structures of vegetative propagation which are capable of giving rise to new offspring are called vegetative propagules, for example: vegetative propagules are runner and sucker, the end tip of the runner can produce buds that develop into new plants that are clones.

Question. What do you understand by fragmentation?
Answer. Fragmentation in multicellular organisms is a form of asexual reproduction in which an organism is split into fragments. Each of these fragments develops into matured, full grown individuals that are identical to their parents.

Question. What is the necessity of reproduction?
Answer. Reproduction prevents all kinds of organisms from becoming extinct. Reproduction is not necessary for carrying out life processes of an individual but helps in increasing the individuals in a population. Reproduction is essential in creating variations in species through genetic recombination.

Question. How encystation is different from sporulation?
Answer. Encystation is a process of becoming enclosed or withdrawn by the organism in a cyst in response to adverse environmental conditions whereas sporulation is a developmental process adopted by organism such as bacteria and fungus into endospores in response to adverse environmental conditions

Question. Define reproduction?
Answer. Reproduction is the biological process by which new individual organisms’ offspring are produced from their parents. The cloning of an organism is a form of asexual reproduction, by asexual reproduction an organism creates a genetically similar or identical copy of itself.

 

Long Answer

Question. State the difference between homothallic and heterothallic?
Answer. 1. Homothallic is the condition of having a haploid phase that produces two kinds of gametes capable of fusing to form a zygote whereas heterothallic is the condition of having two or more morphologically similar haploid phase or types of which individuals from the same type.
2. In homothallic a mating partner is not required whereas in heterothallic two compatible mating partners are required.
3. In homothallic it undergoes with the bisexual reproduction whereas in heterothallic it undergoes with unisexual reproduction.
4. In homothallic it undergoes with self-fertilization whereas in heterothallic it undergoes with cross-fertilization.
5. Homothallic is a mutational event whereas in heterothallic mutations occur in heterothallism.

Question. Explain the pre-fertilisation events?
Answer. Pre-fertilisation is the process that occurs before the actual fertilization, i.e., the process before the fusion of gametes. There are two events that occur before the fertilization.
The two main pre-fertilisation events are:
1. Gametogenesis: Gametogenesis is a biological process by which diploid or haploid precursor cells undergo cell division and differentiation to form mature haploid gametes. The existence of a multicellular, haploid phase in the life cycle between meiosis and gametogenesis is also referred to as alternation of generations. Gametogenesis is important because it is the process that produces your functional gametes (egg and sperm cell) either through meiosis from a diploid cell or mitosis from a haploid cell (plants). These gametes are important because this allows genetically varied organisms (offspring) to be formed.
2. Gamete transfer: The process of bringing together of male and female gamete for fertilization is called gamete transfer. Male and female gametes need to be physically brought together to facilitate fertilization. In most of the organisms, male gamete is motile and female gamete is stationary. In a few fungi and algae both types of gametes are motile. The pollen tube grows to reach the ovary and the ovule. When the pollen tube reaches the ovule, it pushes the male gametes into the egg cell. So, the fusion of the male and the female gamete occurs.

Question. Difference between sexual reproduction and asexual reproduction?
Answer. 1. Sexual reproduction is found in almost all the animals, plants and other life forms including fungi, bacteria, and protists whereas asexual reproduction is found in lower animals and plants, fungi, protozoans, and bacteria.
2. Sexual reproduction is a bi-parental process whereas asexual reproduction is a uni-parental process.
3. Sexual reproduction produces their offspring less rapidly whereas asexual reproduction is involved in the rapid production of offspring in a short time period.
4. The cells undergoing sexual reproduction are mortal whereas the cells undergoing asexual reproduction are considered immortal.
5. Male and female gametes are formed during sexual reproduction whereas gametes are not formed during asexual reproduction.
6. Meiosis, syngamy, and conjugation are involved in the sexual reproduction whereas budding, vegetative reproduction, fragmentation and spore production are the types of asexual reproduction.

Question. Explain the post-fertilisation events?
Answer. The events in sexual reproduction after the formation of the zygote are called post fertilization events. There are two types of post fertilization events:
1. The Zygote: fertilization is defined as the fusion of the male and the female gamete to develop into a diploid zygote. After fertilization, a series of the event occurs in the zygote to develop into a seed. Let us take an overview of the process of post fertilization, endosperm and embryo formation. Development of the zygote depends on the type of the life cycle of the organism. Zygote is the vital link that ensures continuity of the species between the organisms of one generation and the next. Every sexually reproducing organism including the human beings begins life as a single cell the zygote.
2. Embryogenesis: Embryogenesis is defined by a sequential series of dynamic processes that include cell division and growth, and the elaboration of differentiation programs leading to cell fate specification. Embryogenesis is the development of a fertilized egg that occurs early on in pregnancy. After a sperm fuses with an egg, many changes occur in a specific order. The cells divide, reorganize and form layers of tissue that will eventually develop into specific organs, together they form a zygote.

Question. Write short note on fertilisation?
Answer. In sexual reproduction, two parents donate genes to their offspring through a process called fertilization. The resulting young receive a combination of inherited genes. In fertilization, male and female sex cells or gametes fuse to form a single cell called a zygote. The stages of fertilization can be divided into four processes: 1) sperm preparation, 2) sperm-egg recognition and binding, 3) sperm-egg fusion and 4) fusion of sperm and egg pronuclei and activation of the zygote. External fertilization is a mode of reproduction in which a male organism's sperm fertilizes a female organism's egg outside of the female's body. It is contrasted with internal fertilization, in which sperm are introduced via insemination and then combine with an egg inside the body of a female organism. Parthenogenesis is defined as reproduction without fertilization and occurs when the female gamete develops into a new individual without being fertilized by a male gamete.


Question. Cucurbits and papaya plants bear staminate and pistillate flowers. Mention the categories they are put under separately on the basis of the type of flowers they bear. 
Answer. Cucurbits are monoecious plants i.e., they bear both male and female flower on the same plant. On the otherhand, papaya plants are dioecious i.e., both male and female flowers are present on separate plant.

Question. Mention the unique flowering phenomenon exhibited by Strobilanthus kunthiana(neelakuranji). 
Answer. Strobilanthus kunthiana produce flowers once in twelve years.

Question. Name the mode of reproduction that ensures the creation of new variants. 
Answer. Sexual reproduction ensures creation of new variants. It involves, fusion of gametes from different parents which results in genetic recombination that cause variations.

Question. Name the phase all organisms have to pass through before they can reproduce sexually.
Answer. All organisms have to pass through the period of growth known as juvenile or vegetative phase before they start reproducing sexually. The period of growth is between the birth of an individual upto reproductive maturity.

Question. Name the phenomenon and the cell responsible for the development of a new individual without fertilisation as seen in honey bees.
Answer. Female gamete undergoes development to form new individual without fertilisation. This phenomenon is known as parthenogenesis.

Question. Mention the site where syngamy occurs inamphibians and reptiles respectively.
Answer. In amphibians, syngamy takes place outside the body of the organism in water and in reptiles syngamy takes place inside the body of the female organism. Thus, in amphibians external fertilisation takes place and in reptiles internal fertilisation takes place.

Question. Write the difference between staminate and pistillate.
Answer. In flowering plants, staminate is a unisexual male flower which bears stamens only while pistillate is a female flower which bears pistils only.

Question. Why do algae and fungi shift to sexual mode of reproduction just before the onset of adverse conditions? 
Answer. Organisms, such as fungi and algae, switch to sexual mode of reproduction just before the onset of adverse conditions because sexual reproduction brings variation into the individuals, some of which might help the individuals to adapt to the changed environmental condition

Question. Coconut palm is monoecious, while date palm is dioecious. Why are they so called?
Answer. Coconut palm is monoecious because it bears both male and female flowers on the same plant,whereas date palm is said to be dioecious as it bears male and female flowers on separate plants.

Question. The cell division involved in gamete formation is not of the same type in different organisms. Justify. 
Answer. Gametes in all heterogametic species are of two types, male and female. Gametes are haploid though the parent body from which they arise may be either haploid or diploid. Several organisms belonging to monera, fungi, algae and bryophytes have haploid plant body, but organisms belonging to pteridophytes, gymnosperms, angiosperms and most of the animals including human beings, have diploid parental body. Meiosis will take place, if the diploid body has to produce haploid gametes. In diploid organisms, specialised cells called meiocytes undergo meiosis, at the end only one set of chromosome gets incorporated into each gamete.

Question. A list of three flowering plants is given below.
List - Datepalm, cucurbits and pea.
Which ones out them are
(a) monoecious and
(b) bearing pistillate flowers? 
Answer. (a) Cucurbits and pea plants are monoecious bearing both staminate and pistillate flowers on the same plant.
(b) Date palm, cucurbits and pea, all three bear pistillate flowers.

Question. Name any two organisms and the phenomenon involved where the female gamete undergoes development to form new organisms without fertilisation.
Answer. The phenomenon where female gamete undergoes development to form new organism without fertilisation is called parthenogenesis. It occurs in honeybees and rotifers. 

Please click on below link to download CBSE Class 12 Biology Reproduction in Organisms Worksheet Set A

More Study Material

CBSE Class 12 Biology Chapter 1 Reproduction in Organisms Worksheet

The above practice worksheet for Chapter 1 Reproduction in Organisms has been designed as per the current syllabus for Class 12 Biology released by CBSE. Students studying in Class 12 can easily download in Pdf format and practice the questions and answers given in the above practice worksheet for Class 12 Biology on a daily basis. All the latest practice worksheets with solutions have been developed for Biology by referring to the most important and regularly asked topics that the students should learn and practice to get better scores in their examinations. Studiestoday is the best portal for Printable Worksheets for Class 12 Biology students to get all the latest study material free of cost.

Worksheet for Biology CBSE Class 12 Chapter 1 Reproduction in Organisms

Teachers of studiestoday have referred to the NCERT book for Class 12 Biology to develop the Biology Class 12 worksheet. If you download the practice worksheet for the above chapter daily, you will get better scores in Class 12 exams this year as you will have stronger concepts. Daily questions practice of Biology printable worksheet and its study material will help students to have a stronger understanding of all concepts and also make them experts on all scoring topics. You can easily download and save all revision Worksheets for Class 12 Biology also from www.studiestoday.com without paying anything in Pdf format. After solving the questions given in the practice sheet which have been developed as per the latest course books also refer to the NCERT solutions for Class 12 Biology designed by our teachers

Chapter 1 Reproduction in Organisms worksheet Biology CBSE Class 12

All practice paper sheet given above for Class 12 Biology have been made as per the latest syllabus and books issued for the current academic year. The students of Class 12 can be assured that the answers have been also provided by our teachers for all test paper of Biology so that you are able to solve the problems and then compare your answers with the solutions provided by us. We have also provided a lot of MCQ questions for Class 12 Biology in the worksheet so that you can solve questions relating to all topics given in each chapter. All study material for Class 12 Biology students have been given on studiestoday.

Chapter 1 Reproduction in Organisms CBSE Class 12 Biology Worksheet

Regular printable worksheet practice helps to gain more practice in solving questions to obtain a more comprehensive understanding of Chapter 1 Reproduction in Organisms concepts. Practice worksheets play an important role in developing an understanding of Chapter 1 Reproduction in Organisms in CBSE Class 12. Students can download and save or print all the printable worksheets, assignments, and practice sheets of the above chapter in Class 12 Biology in Pdf format from studiestoday. You can print or read them online on your computer or mobile or any other device. After solving these you should also refer to Class 12 Biology MCQ Test for the same chapter.

Worksheet for CBSE Biology Class 12 Chapter 1 Reproduction in Organisms

CBSE Class 12 Biology best textbooks have been used for writing the problems given in the above worksheet. If you have tests coming up then you should revise all concepts relating to Chapter 1 Reproduction in Organisms and then take out a print of the above practice sheet and attempt all problems. We have also provided a lot of other Worksheets for Class 12 Biology which you can use to further make yourself better in Biology

Where can I download latest CBSE Practice worksheets for Class 12 Biology Chapter 1 Reproduction in Organisms

You can download the CBSE Practice worksheets for Class 12 Biology Chapter 1 Reproduction in Organisms for the latest session from StudiesToday.com

Can I download the Practice worksheets of Class 12 Biology Chapter 1 Reproduction in Organisms in Pdf

Yes, you can click on the links above and download chapter-wise Practice worksheets in PDFs for Class 12 for Biology Chapter 1 Reproduction in Organisms

Are the Class 12 Biology Chapter 1 Reproduction in Organisms Practice worksheets available for the latest session

Yes, the Practice worksheets issued for Chapter 1 Reproduction in Organisms Class 12 Biology have been made available here for the latest academic session

How can I download the Chapter 1 Reproduction in Organisms Class 12 Biology Practice worksheets

You can easily access the links above and download the Class 12 Practice worksheets Biology for Chapter 1 Reproduction in Organisms

Is there any charge for the Practice worksheets for Class 12 Biology Chapter 1 Reproduction in Organisms

There is no charge for the Practice worksheets for Class 12 CBSE Biology Chapter 1 Reproduction in Organisms you can download everything free

How can I improve my scores by solving questions given in Practice worksheets in Chapter 1 Reproduction in Organisms Class 12 Biology

Regular revision of practice worksheets given on studiestoday for Class 12 subject Biology Chapter 1 Reproduction in Organisms can help you to score better marks in exams

Are there any websites that offer free Practice test papers for Class 12 Biology Chapter 1 Reproduction in Organisms

Yes, studiestoday.com provides all the latest Class 12 Biology Chapter 1 Reproduction in Organisms test practice sheets with answers based on the latest books for the current academic session

Can test sheet papers for Chapter 1 Reproduction in Organisms Class 12 Biology be accessed on mobile devices

Yes, studiestoday provides worksheets in Pdf for Chapter 1 Reproduction in Organisms Class 12 Biology in mobile-friendly format and can be accessed on smartphones and tablets.

Are practice worksheets for Class 12 Biology Chapter 1 Reproduction in Organisms available in multiple languages

Yes, practice worksheets for Class 12 Biology Chapter 1 Reproduction in Organisms are available in multiple languages, including English, Hindi