Frank Brothers Solutions for ICSE Class 9 Biology Chapter 2 Being Alive What Is Its Meaning

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Answer 1: Characteristics of living organisms are:
1. All living organisms exhibit a definite shape and size. For example – Mango trees can be identified among all the other tress. Also tigers can be identified among other animals.
2. All living beings show some type of body organization. Their body may be made of one cell in case of unicellular organisms or many cells in case of multicellular organisms. In multicellular organisms, cells are further organized into tissues, organs and organ systems.
3. Living organisms show autotrophic or heterotrophic modes of nutrition.
4. All living organisms respire continuously. During respiration, most organisms use up oxygen from environment and release carbon dioxide. This oxygen oxidizes food materials to release energy which is used to carry out the various life processes of the organism.
5. In all living organisms, many chemical processes occur in order to maintain life and this is called metabolism. Some of these processes are constructive called anabolic processes whereas others are destructive called catabolic processes.
6. All living organisms show the characteristic feature of growth. From a small size at birth, living organisms grow due to formation of new cells and building up of protoplasm within cells. Example – A seedling growing into a small plant and then into a big tree.
7. Reproduction helps in producing offsprings similar to parents and thus helps in maintaining continuity of race.
8. All living organisms show some form of movement or another. This may be movement of the entire body from one place to another as seen in most animals, few plants and certain plant organs, or movement of a part of the body only.
9. All living organisms excrete waste products of metabolism from their body.
10. Every living organism shows a definite life-cycle including four stages i.e. birth, growth, maturity and death. Every living organism has a definite life-span.
Living things are distinct because they show complex behaviors like growth and reproduction. These features collectively ensure that life continues on Earth through different generations.
Teacher's Tip: Use the mnemonic "MRS GREN" to remember Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, and Nutrition.
Exam Tip: For long-answer questions about characteristics, try to provide a specific example for each point to secure full marks.

Answer 2: Organisms capable of performing all the vital activities of life like nutrition, growth, respiration, digestion and excretion etc. are called living organisms. Example – man, bird, fish, trees. Things which do not perform any vital life activities are called non-living things. Example – pen, table, stone, water, car etc. Non-living things require external energy for their movement (car, train etc.) or addition of particles from outside for increase in size (eg. increase in size of alum crystals in their concentrated solutions). Growing of the crystal of copper sulphate is not a living character. This is because the increase in its size is due to deposition of new material externally and not from within. This is known as extrinsic growth. In living organisms, growth occurs due to formation of new cells and building up of protoplasm within cells.
Non-living things remain unchanged unless acted upon by external forces. Living things grow from within by using energy they produce themselves through internal biological processes.
Teacher's Tip: Remember that living growth is "Intrinsic" (from inside) while crystal growth is "Extrinsic" (from outside).
Exam Tip: If asked why a crystal is non-living despite growing, always specify that it grows by adding material to its surface, not by cell division.

Answer 3: A motor car requires external energy for its movement and also it does not perform the vital life activities on its own, hence it is not a living organism. A living organism has internal energy which is used for carrying out all its vital life activities.
A car might move and "breathe" exhaust, but it cannot repair itself or reproduce. It depends entirely on humans to provide fuel and control its operations.
Teacher's Tip: Movement alone is not enough to be called "alive"; an object must show all life characteristics.
Exam Tip: Point out the absence of "metabolism" and "reproduction" to explain why machines are non-living.

Answer 4: (a) Irritability is a feature shown by living beings, but not non-living things. It refers to the ability of the organism to respond in accordance with internal or external environmental stimuli. Irritability is well-developed in animals due to the evolution of nervous system. An example is the immediate removal of hand from a hot object. Irritability is also shown by plants but it is not very prominent.
(b) Metabolism – In all living organisms, many chemical processes occur constantly in order to maintain life and this is called metabolism. Metabolism includes two types of processes i.e. constructive and destructive. Only living organisms show metabolism.
(c) Respiration – All living organisms respire continuously. During respiration, most organisms use up oxygen from environment and release carbon dioxide.
(d) Cellular structure - All living organisms are made up of one or many cells. Each cell contains protoplasm wherein all the life activities are carried out. Protoplasm is surrounded by a thin, elastic plasma membrane. Plant cells possess an additional cell wall to provide rigidity to the cells.
(e) Growth – All living organisms show the characteristic feature of growth.From a small size at birth, living organisms grow due to formation of new cells and building up of protoplasm within cells. Example – A seedling growing into a small plant and then into a big tree.
These biological processes are the foundation of life that keeps every organism functioning. Without these internal mechanisms, an organism would cease to exist and eventually become dead matter.
Teacher's Tip: Metabolism is like a chemical kitchen inside every cell where energy is prepared and used.
Exam Tip: Use the term "stimuli" specifically when defining irritability to demonstrate scientific accuracy.

Answer 5: The characters of living organisms are:
1. Growth
2. Reproduction
3. Metabolism
4. Respiration
5. Nutrition
6. Movement and locomotion
7. Definite form and size
8. Reproduction
9. Excretion
10. Irritability
(Write any four)
This list identifies the fundamental traits that differentiate biological life from physical objects. Every living creature, from a tiny bacterium to a giant whale, shares these essential properties.
Teacher's Tip: Focus on the "Big Four": Respiration, Nutrition, Growth, and Reproduction.
Exam Tip: When an exam asks for "any four" points, pick the ones you can explain with the best examples.

Answer 6: A rolling stone just rolls down due to gravitational force acting on it. It will stop rolling once it reaches a hurdle or plain ground. Then it cannot roll or move on its own. It needs some external force to cause its movement. Hence it is a non-living object. A living organism would be able to move by itself using its own energy, without depending on external force.
Gravity is a physical force that moves objects, but it is not a sign of life. Biological movement is driven by an organism's own muscles and internal energy stores.
Teacher's Tip: A stone moves because it is "pushed"; a cat moves because it "wants" to.
Exam Tip: Always mention that living movement is "self-directed" and uses "internal energy."

Answer 7: Living – Egg, protoplasm, cactus, flower, seed
Non-living – Table, glass, iron, car, nail
Dead – Coral, leather, cork
"Dead" objects are those that were once part of a living system but have lost their vital functions. "Non-living" objects like iron or glass were never part of a biological organism.
Teacher's Tip: If it came from a tree (like cork or a wooden table), it is classified as "Dead" because it once had life.
Exam Tip: Be careful classifying items like seeds; they are living because they have the potential to grow into a plant.

Answer 8: Examples of movement in living things –
Running of a lion
Drooping of leaves
Examples of movement in non-living things –
Running of train or car
Rolling down of a stone
Animals move their whole bodies to find food or escape danger, which we call locomotion. Plants show movement by bending their parts toward the sun or closing their leaves when touched.
Teacher's Tip: Plants don't have legs, but they move by changing how they grow toward light!
Exam Tip: Provide one animal example and one plant example for living movement to show a complete understanding.

Answer 9: (a) Life is the condition that distinguishes organisms from inorganic objects and dead organisms.
(b) Death is the cessation of all life activities in a living being due to weakening and losing of energy from them after completing their life span
(c) Locomotion is the movement of the entire organism from one place to another.
(d) Reproduction is the ability of living organisms to produce young ones that are similar to parents.
Reproduction is the biological mechanism that ensures species continue through time without going extinct. Death marks the irreversible end of an organism's ability to maintain its internal environment.
Teacher's Tip: Think of "Life Span" as the natural timer every living creature has.
Exam Tip: Define "Locomotion" as the movement of the *entire* body to distinguish it from simple internal part movements.

Answer 10:
(a) Feeding: It is the act of consuming food
Nutrition: The taking in and assimilation of food material for the purpose of building up tissue and liberating energy
(b) Ingestion: Taking in of food into the body is called ingestion
Egestion: Removal of undigested and waste food from body is called egestion
(c) Movement: It includes movement of any body part as well as the entire organism. It is exhibited by all living organisms.
Locomotion: It refers to movement of the entire organism from one place to another. It is mainly shown by animals.
(d) Catabolic process: It is the destructive process of metabolism in which complex substances are broken down into simpler units.
Anabolic process: It is the constructive process of metabolism in which substances are synthesized.
(e) Autotrophic nutrition: In this mode of nutrition, the organisms prepare their own food from simple inorganic materials. This nutrition is shown by plants.
Heterotrophic nutrition: In this mode of nutrition, the organisms cannot prepare their own food but depend directly or indirectly on autotrophs. This nutrition is shown by most animals.
While feeding is a simple act, nutrition involves the whole journey of food turning into energy and body parts. Anabolism and catabolism are like building a house and then breaking down scrap materials for heat.
Teacher's Tip: Use this simple trick: "Ana" Builds (Anabolic) and "Cata" Cuts (Catabolic).
Exam Tip: For comparison questions, always use separate blocks or a T-table to clearly show the differences.

Answer 11: Characteristics of living organisms are:
1. (i) All living organisms exhibit a definite shape and size. For example – Mango trees can be identified among all the other tress. Also tigers can be identified among other animals.
2. All living beings show some type of body organization. Their body may be made of one cell in case of unicellular organisms or many cells in case of multicellular organisms. In multicellular organisms, cells are further organized into tissues, organs and organ systems.
3. Living organisms show autotrophic or heterotrophic modes of nutrition.
4. All living organisms respire continuously. During respiration, most organisms use up oxygen from environment and release carbon dioxide. This oxygen oxidizes food materials to release energy which is used to carry out the various life processes of the organism.
5. In all living organisms, many chemical processes occur in order to maintain life and this is called metabolism. Some of these processes are constructive called anabolic processes whereas others are destructive called catabolic processes.
6. All living organisms show the characteristic feature of growth. From a small size at birth, living organisms grow due to formation of new cells and building up of protoplasm within cells. Example – A seedling growing into a small plant and then into a big tree.
7. Reproduction helps in producing offsprings similar to parents and thus helps in maintaining continuity of race.
8. All living organisms show some form of movement or another. This may be movement of the entire body from one place to another as seen in most animals, few plants and certain plant organs, or movement of a part of the body only.
9. All living organisms excrete waste products of metabolism from their body.
10. Every living organism shows a definite life-cycle including four stages i.e. birth, growth, maturity and death. Every living organism has a definite life-span.
These traits provide a universal checklist to determine if something belongs to the biological world. Each characteristic works together to help the organism survive in its specific environment.
Teacher's Tip: Remember that life is a cycle that always begins with birth and ends with death.
Exam Tip: If you forget a characteristic, think about your own body functions like breathing (respiration) and eating (nutrition).

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Answer 12:
1. (a) Protoplasm
2. (b) Dried bone
3. (a) Living
4. (d) The capacity to respond to the stimuli
5. (a) Cell
6. (c) Reproduction
Protoplasm is often called the "physical basis of life" because it is where all vital activities happen. Irritability is the fancy scientific name for how living things react when something happens to them.
Teacher's Tip: The cell is the smallest unit of life, just like a brick is the smallest unit of a wall.
Exam Tip: In Multiple Choice Questions (MCQs), read all options carefully as two answers might seem similar but only one is scientifically accurate.