1. Name the resulting cell which gives rise to a new individual after fertilisation.
(Hint: zygote)
2. What is the term given to animals that lay eggs in which fertilisation occurs outside the body?
(Hint: Oviparous with external fertilisation.)
3. Name the organism which reproduces by budding.
(Hint: Hydra)
4. Name some processes which are essential for the survival of individuals.
4. Name some processes which are essential for the survival of individuals.
[Hint: Digestion, circulation, excretion, and respiration.]
5. In the list of animals given below, the hen is the odd one out. State the reason for this.
A human being, cow, dog, hen
5. In the list of animals given below, the hen is the odd one out. State the reason for this.
A human being, cow, dog, hen
(Hint: It is oviparous.)
6. Which of the following shows metamorphosis?
i)Ant ii) Cat iii) Tadpole iv) Fish
7. Which of the following is not viviparous?
i) Humans ii) Shark iii) Snail iv) Dolphin
8) Why do animals exhibiting external fertilisation produce a large number of gametes?
(Hint: To ensure a better chance of fertilisation)
9) Where does the development of the embryo take place in the body of a female? (Hint: The embryo develops in the uterus of the female reproductive organ.)
10) Define reproduction
(Hint: The production of new organisms from the existing organisms of the same species )
For question numbers 11 to 13, two statements are given- one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (i), (ii), (iii), and (iv) as given below.
i) Both A and R are true and R is the correct explanation of the assertion. ii) Both A and R are true but R is not the correct explanation of the assertion iii) A is true but R is false. iv) A is false but R is true.
11. Assertion(A): Hens and Ducks are called Oviparous animals.
Reason(R): Oviparous animals lay eggs.
i) Both A and R are true and R is the correct explanation of the assertion.
12. Assertion(A): The fusion of sperm and ovum is called fertilisation.
Reason(R): Fertilisation occurs only in birds.
iii) A is true but R is false.
13. Assertion(A): Hydra produces young ones by the process of budding.
Reason(R): An amoeba reproduces by the process of binary fission. ii) Both A and R are true but R is not the correct explanation of the assertion II.PASSSAGE BASED
Read the passage carefully and answer the questions that follow-
For the continuity of life, all living things produce organisms of their own kind. This is called reproduction. A special organ system called the reproductive system is responsible for carrying out the process of reproduction in a living body. Although all living things reproduce they do so by different means. There are two types of Reproduction-Asexual and Sexual reproduction. Asexual reproduction requires one parent while Sexual reproduction requires two parents to produce a baby. Asexual reproduction is the simplest form of reproduction and is commonly found in plants and lower animals like starfish, sponges and worms. Most plants and mammals, including human beings, reproduce sexually.
a)What is reproduction?
i) Producing fruits
ii) Producing young ones of its own kind iii) Producing food iv) All of these
b)What are the two types of reproduction?
i)Budding ii) Fragmentation iii) Asexual reproduction iv) Sexual reproduction
a. i) b. ii) c. ii&iv d. iii &iv
c)Which type of reproduction involves only one parent?
i)Sexual reproduction ii)Asexual reproduction iii)Both of these iv) None of these
d)How do mammals reproduce?
i) By sexual reproduction ii) By asexual reproduction iii) By budding
iv) All of these
e)Identify the organism which reproduces asexually. i)Shark ii)Sponges
iii)Snake
iv)Snail
III.CASE STUDY-BASED QUESTIONS
(a) Saima learned from her teacher that cloning is the production of an exact or a true copy of a cell, any other living part, or a complete organism by asexual reproduction. Cloning of an animal was successfully
performed for the first time by Ian Wilmut and his colleagues at the Roslin Institute in Edinburgh, Scotland. They cloned the sheep named Dolly on July 5, 1996.
In the process of cloning Dolly, a cell was collected from the mammary gland of a female Finn Dorsett sheep. Meanwhile, an egg was obtained from a Scottish blackface ewe. The nucleus was removed from the egg. Then, the nucleus of the mammary gland cell from the Finn Dorsett sheep was inserted into the egg of the Scottish blackface ewe whose nucleus had been removed. This egg was implanted into the Scottish blackface ewe. The egg developed normally and finally Dolly was born. The cloning of Dolly was a successful attempt. However, many clones often die soon after birth. Sometimes cloning also leads to certain abnormalities among clones. Unfortunately, Dolly died on 14th February 2003 due to a certain lung disease.
i)What is cloning?
(Hint: cloning is the production of an exact or a true copy of a cell, any other living part, or a complete organism by asexual reproduction.) ii)Name the first cloned animal. (Hint: Dolly) iii)Who performed cloning for the first time? (Hint: Ian Wilmut and colleagues ) iv)State the disadvantage of cloning.
(Hint: Many clones often die soon after birth. Sometimes cloning also leads to certain abnormalities among clones. )
(b) Animal A which is classified as an amphibian lays eggs in pond water. The hatching of its eggs produces a tailed form B which looks very different from animal A. The form B then undergoes a change
C and then looks like the adult organism A (i) Identify animal A and form B
(Hint: animal A -Frog and form B tadpole)
(ii) What is the change C known as and define C
(Hint: Metamorphosis, The transformation of the larva into an adult through drastic changes)
IV. a) SHORT ANSWER TYPE QUESTIONS (2 M):
1. What is metamorphosis? (Hint: The transformation of the larva into an adult through drastic changes where the larva looks entirely different from the adult is called metamorphosis.) 2.a) What are gametes? (Hint: Gametes are an organism's reproductive cells. They are also referred to as sex cells.
b) Name the gametes produced in humans. (Sperm-male gamete and ovum-female gamete)
c) Why do only male gametes have a tail? (Hint: Because sperm need to be motile to reach a non-motile egg in the ovary of a female for fertilisation.)
3. Although 2 cells called gametes fuse, the product formed is a single cell called a zygote. Justify. (Hint: During fertilisation only nuclei of the sperm and the egg fuse to form a zygote. Then sperm degenerates. The two gametes have 23 chromosomes each. So, when they fuse they form a complete cell with 46 chromosomes with characteristics of both the parents).
4. a) What are the various methods of asexual reproduction? (Hint: Budding and binary fission)
b) Two small organisms X and Y both reproduce by the method of budding. Organism X is industrially very important because it is used in making alcohol from sugar. It is also used in making bread. Organism Y is an aquatic organism having tentacles.
(i) Identify organisms X and Y(Hint :X-Yeast and Y-Hydra)
(ii) Name the process in which X converts sugar into alcohol(Hint: Fermentation) (iii) Out of X and Y which organism is multicellular and which one is unicellular?
(Hint: X -Unicellular Y- Multicellular)
IV. b) SHORT ANSWER TYPE QUESTIONS (3 M):
1. How is reproduction in hydra different from that in amoeba? (Hint: Hydra reproduces by budding where a bud detaches from the parent and grows into a complete organism. Whereas amoeba reproduces by binary fission. The process of reproduction begins with the division of its nucleus into two. This is followed by the division of its body into two.)
2. Explain the life cycle of a frog with a diagram.
(Hint: The life cycle of a frog has three distinct stages: Eggs → Tadpole (larva) → Adult frog
Female frogs lay eggs. These eggs hatch into larvae known as tadpoles. The tadpoles are fish-like and have gills, a tail, and a small circular mouth. They can swim freely in the water. After a few weeks, tadpoles grow and undergo some abrupt changes in their structure through cell growth and development. As a result of such changes, the tadpoles are gradually transformed into frogs.)
3. Differentiate between external and internal fertilisation? (Hint-Internal- the fusion of male and female gametes takes place inside the body, there are high chances of survival of offspring, fewer numbers of eggs are produced, Cows, Hens, Human beings, etc.
External-the fusion of male and female gametes takes place outside the body, there are low chances of survival of offspring, and large numbers of eggs are produced, Fish, Frog.)
4. Explain binary fission in amoeba with a neat labelled diagram.
Binary fission: In binary fission, a single parent cell is divided into two equal individual cells as in Amoeba. It divides into two by division of their bodies, each of them gets one nucleus and develops into a separate individual. The figure given below shows how binary fission occurs in amoeba
5. What is the difference between sexual and asexual reproduction?
Sexual Reproduction
Asexual Reproduction
Two parents are involved.
A single parent is involved.
Gametes are formed.
Gametes are not formed.
Fertilisation takes place.
Fertilisation does not take place.
Examples: humans, frogs, bird, etc.
Examples: amoeba, hydra, sponge, etc.
6. With a neat labelled diagram explain the mode of reproduction in hydra.
Budding: In budding, the organism develops a bulge called bud which further develops into an adult organism and separates itself from the parent body to lead an independent life. This type of reproduction is shown in Hydra. The following figure shows the budding in Hydra.
7. Explain what happens after a hen lays a fertilised egg?
(Hint: After laying an egg, the hen sits on the egg to keep it warm. Development of the chick takes place inside the shell. It takes about 3 weeks for the embryo to develop into a chick. After its development is complete, the chick comes out by bursting open the eggshell.)
8. Why do frogs produce a large number of gametes? (Hint-Frogs produce a large number of gametes because there are always chances of getting eaten by fish present in the water or getting washed out by wind currents and rainfall. In order to increase the chances of fertilisation, frogs lay a greater number of eggs.)
9. Briefly explain cloning.
(Hint: Cloning is the production of an exact copy of an animal by means of asexual reproduction. The nucleus of a normal body cell of the animal is transferred into an empty egg cell. The newly formed egg cell is allowed to develop normally. An exact copy of the animal is produced.
10. Why is the young one of a frog called a larva and not a baby frog? (Hint: - Because tadpole is the first stage of incomplete metamorphosis. This incomplete metamorphosis has only larval and adult stages and no pupal stages so the young one is called a larva and not a baby frog.)
V. LONG ANSWER TYPE QUESTIONS (5 M):
1. a) Briefly explain in-vitro fertilization. (Hint: It is a method in which the ovum collected from a female’s body is allowed to fuse with sperm collected from a male’s body in an external medium or outside the body of the female. The zygote so developed is allowed to grow in vitro (i.e.in glass) for about a week and then implanted in the female’s uterus where it further develops as a normal embryo. A baby born of this technique is often called a ‘test tube baby’.) b. Observe the given figure and answer the questions that follow.
b.1) Label A and B- Sperm and egg.
b. 2) Identify the process- fertilisation
b.3) What happens during the process and what is formed? (Hint- the sperm nucleus fuses with the egg nucleus as a result of which a zygote is formed.)
c)How would you distinguish between an embryo, a zygote and foetus?
(Hint: Zygote- It is a single cell formed by the fusion of male and female gametes
Embryo- When a zygote divides repeatedly to form a ball of hundred cells. Thus, an unborn baby at an early stage of development in the uterus is called an embryo.
Foetus- An unborn baby in the uterus at the stage when all the body parts can be identified.) d)
Can the process of a child changing into an adult be called metamorphosis?
(Hint: No, the process of a child changing into an adult cannot be called metamorphosis because the
basic body structure does not change.)
b) Why is it that dogs always produce several puppies whereas human beings usually produce only one
child at a time? (Hint: Dogs produce more than one egg at a time. Hence, more puppies are born to
them at the same time. Whereas humans usually produce one egg at a time, hence produce only one
child at a time)
c)Under what circumstances can twins be born in humans? (Hint: Twins are born when two eggs are
produced and fertilised by two sperms or when a single zygote splits and forms two embryos)
2) a) Why are not all animals oviparous? Does vivipary offer any advantage to organisms? (Hint: -All animals are not oviparous because being viviparous offer certain advantages over oviparous animals. Oviparous animals are those animals that reproduce by laying eggs and viviparous animals are those animals which reproduce by giving birth directly to the baby. After laying eggs, the mother needs to take care of the egg like by hatching it and saving it from predators. But in the case of a viviparous baby develop inside the mother's womb and take nutrients from
the mother and she does not worry about predators also.)
d) List the functions of the jelly cover around the frog’s egg. (Hint: There are lots of functions that the jelly in a frog's egg can provide. Firstly, it helps to keep the eggs together, or else they may float with water. Secondly, it acts as a protective covering so that the eggs do not die. Thirdly it protects the egg from any kind of injury.)
6. Which of the following shows metamorphosis?
i)Ant ii) Cat iii) Tadpole iv) Fish
7. Which of the following is not viviparous?
i) Humans ii) Shark iii) Snail iv) Dolphin
8) Why do animals exhibiting external fertilisation produce a large number of gametes?
(Hint: To ensure a better chance of fertilisation)
9) Where does the development of the embryo take place in the body of a female? (Hint: The embryo develops in the uterus of the female reproductive organ.)
10) Define reproduction
(Hint: The production of new organisms from the existing organisms of the same species )
For question numbers 11 to 13, two statements are given- one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (i), (ii), (iii), and (iv) as given below.
i) Both A and R are true and R is the correct explanation of the assertion. ii) Both A and R are true but R is not the correct explanation of the assertion iii) A is true but R is false. iv) A is false but R is true.
11. Assertion(A): Hens and Ducks are called Oviparous animals.
Reason(R): Oviparous animals lay eggs.
i) Both A and R are true and R is the correct explanation of the assertion.
12. Assertion(A): The fusion of sperm and ovum is called fertilisation.
Reason(R): Fertilisation occurs only in birds.
iii) A is true but R is false.
13. Assertion(A): Hydra produces young ones by the process of budding.
Reason(R): An amoeba reproduces by the process of binary fission. ii) Both A and R are true but R is not the correct explanation of the assertion II.PASSSAGE BASED
Read the passage carefully and answer the questions that follow-
For the continuity of life, all living things produce organisms of their own kind. This is called reproduction. A special organ system called the reproductive system is responsible for carrying out the process of reproduction in a living body. Although all living things reproduce they do so by different means. There are two types of Reproduction-Asexual and Sexual reproduction. Asexual reproduction requires one parent while Sexual reproduction requires two parents to produce a baby. Asexual reproduction is the simplest form of reproduction and is commonly found in plants and lower animals like starfish, sponges and worms. Most plants and mammals, including human beings, reproduce sexually.
a)What is reproduction?
i) Producing fruits
ii) Producing young ones of its own kind iii) Producing food iv) All of these
b)What are the two types of reproduction?
i)Budding ii) Fragmentation iii) Asexual reproduction iv) Sexual reproduction
a. i) b. ii) c. ii&iv d. iii &iv
c)Which type of reproduction involves only one parent?
i)Sexual reproduction ii)Asexual reproduction iii)Both of these iv) None of these
d)How do mammals reproduce?
i) By sexual reproduction ii) By asexual reproduction iii) By budding
iv) All of these
e)Identify the organism which reproduces asexually. i)Shark ii)Sponges
iii)Snake
iv)Snail
III.CASE STUDY-BASED QUESTIONS
(a) Saima learned from her teacher that cloning is the production of an exact or a true copy of a cell, any other living part, or a complete organism by asexual reproduction. Cloning of an animal was successfully
performed for the first time by Ian Wilmut and his colleagues at the Roslin Institute in Edinburgh, Scotland. They cloned the sheep named Dolly on July 5, 1996.
In the process of cloning Dolly, a cell was collected from the mammary gland of a female Finn Dorsett sheep. Meanwhile, an egg was obtained from a Scottish blackface ewe. The nucleus was removed from the egg. Then, the nucleus of the mammary gland cell from the Finn Dorsett sheep was inserted into the egg of the Scottish blackface ewe whose nucleus had been removed. This egg was implanted into the Scottish blackface ewe. The egg developed normally and finally Dolly was born. The cloning of Dolly was a successful attempt. However, many clones often die soon after birth. Sometimes cloning also leads to certain abnormalities among clones. Unfortunately, Dolly died on 14th February 2003 due to a certain lung disease.
i)What is cloning?
(Hint: cloning is the production of an exact or a true copy of a cell, any other living part, or a complete organism by asexual reproduction.) ii)Name the first cloned animal. (Hint: Dolly) iii)Who performed cloning for the first time? (Hint: Ian Wilmut and colleagues ) iv)State the disadvantage of cloning.
(Hint: Many clones often die soon after birth. Sometimes cloning also leads to certain abnormalities among clones. )
(b) Animal A which is classified as an amphibian lays eggs in pond water. The hatching of its eggs produces a tailed form B which looks very different from animal A. The form B then undergoes a change
C and then looks like the adult organism A (i) Identify animal A and form B
(Hint: animal A -Frog and form B tadpole)
(ii) What is the change C known as and define C
(Hint: Metamorphosis, The transformation of the larva into an adult through drastic changes)
IV. a) SHORT ANSWER TYPE QUESTIONS (2 M):
1. What is metamorphosis? (Hint: The transformation of the larva into an adult through drastic changes where the larva looks entirely different from the adult is called metamorphosis.) 2.a) What are gametes? (Hint: Gametes are an organism's reproductive cells. They are also referred to as sex cells.
b) Name the gametes produced in humans. (Sperm-male gamete and ovum-female gamete)
c) Why do only male gametes have a tail? (Hint: Because sperm need to be motile to reach a non-motile egg in the ovary of a female for fertilisation.)
3. Although 2 cells called gametes fuse, the product formed is a single cell called a zygote. Justify. (Hint: During fertilisation only nuclei of the sperm and the egg fuse to form a zygote. Then sperm degenerates. The two gametes have 23 chromosomes each. So, when they fuse they form a complete cell with 46 chromosomes with characteristics of both the parents).
4. a) What are the various methods of asexual reproduction? (Hint: Budding and binary fission)
b) Two small organisms X and Y both reproduce by the method of budding. Organism X is industrially very important because it is used in making alcohol from sugar. It is also used in making bread. Organism Y is an aquatic organism having tentacles.
(i) Identify organisms X and Y(Hint :X-Yeast and Y-Hydra)
(ii) Name the process in which X converts sugar into alcohol(Hint: Fermentation) (iii) Out of X and Y which organism is multicellular and which one is unicellular?
(Hint: X -Unicellular Y- Multicellular)
IV. b) SHORT ANSWER TYPE QUESTIONS (3 M):
1. How is reproduction in hydra different from that in amoeba? (Hint: Hydra reproduces by budding where a bud detaches from the parent and grows into a complete organism. Whereas amoeba reproduces by binary fission. The process of reproduction begins with the division of its nucleus into two. This is followed by the division of its body into two.)
2. Explain the life cycle of a frog with a diagram.
(Hint: The life cycle of a frog has three distinct stages: Eggs → Tadpole (larva) → Adult frog
Female frogs lay eggs. These eggs hatch into larvae known as tadpoles. The tadpoles are fish-like and have gills, a tail, and a small circular mouth. They can swim freely in the water. After a few weeks, tadpoles grow and undergo some abrupt changes in their structure through cell growth and development. As a result of such changes, the tadpoles are gradually transformed into frogs.)
3. Differentiate between external and internal fertilisation? (Hint-Internal- the fusion of male and female gametes takes place inside the body, there are high chances of survival of offspring, fewer numbers of eggs are produced, Cows, Hens, Human beings, etc.
External-the fusion of male and female gametes takes place outside the body, there are low chances of survival of offspring, and large numbers of eggs are produced, Fish, Frog.)
4. Explain binary fission in amoeba with a neat labelled diagram.
Binary fission: In binary fission, a single parent cell is divided into two equal individual cells as in Amoeba. It divides into two by division of their bodies, each of them gets one nucleus and develops into a separate individual. The figure given below shows how binary fission occurs in amoeba
5. What is the difference between sexual and asexual reproduction?
Sexual Reproduction
Asexual Reproduction
Two parents are involved.
A single parent is involved.
Gametes are formed.
Gametes are not formed.
Fertilisation takes place.
Fertilisation does not take place.
Examples: humans, frogs, bird, etc.
Examples: amoeba, hydra, sponge, etc.
6. With a neat labelled diagram explain the mode of reproduction in hydra.
Budding: In budding, the organism develops a bulge called bud which further develops into an adult organism and separates itself from the parent body to lead an independent life. This type of reproduction is shown in Hydra. The following figure shows the budding in Hydra.
7. Explain what happens after a hen lays a fertilised egg?
(Hint: After laying an egg, the hen sits on the egg to keep it warm. Development of the chick takes place inside the shell. It takes about 3 weeks for the embryo to develop into a chick. After its development is complete, the chick comes out by bursting open the eggshell.)
8. Why do frogs produce a large number of gametes? (Hint-Frogs produce a large number of gametes because there are always chances of getting eaten by fish present in the water or getting washed out by wind currents and rainfall. In order to increase the chances of fertilisation, frogs lay a greater number of eggs.)
9. Briefly explain cloning.
(Hint: Cloning is the production of an exact copy of an animal by means of asexual reproduction. The nucleus of a normal body cell of the animal is transferred into an empty egg cell. The newly formed egg cell is allowed to develop normally. An exact copy of the animal is produced.
10. Why is the young one of a frog called a larva and not a baby frog? (Hint: - Because tadpole is the first stage of incomplete metamorphosis. This incomplete metamorphosis has only larval and adult stages and no pupal stages so the young one is called a larva and not a baby frog.)
V. LONG ANSWER TYPE QUESTIONS (5 M):
1. a) Briefly explain in-vitro fertilization. (Hint: It is a method in which the ovum collected from a female’s body is allowed to fuse with sperm collected from a male’s body in an external medium or outside the body of the female. The zygote so developed is allowed to grow in vitro (i.e.in glass) for about a week and then implanted in the female’s uterus where it further develops as a normal embryo. A baby born of this technique is often called a ‘test tube baby’.) b. Observe the given figure and answer the questions that follow.
b.1) Label A and B- Sperm and egg.
b. 2) Identify the process- fertilisation
b.3) What happens during the process and what is formed? (Hint- the sperm nucleus fuses with the egg nucleus as a result of which a zygote is formed.)
c)How would you distinguish between an embryo, a zygote and foetus?
(Hint: Zygote- It is a single cell formed by the fusion of male and female gametes
Embryo- When a zygote divides repeatedly to form a ball of hundred cells. Thus, an unborn baby at an early stage of development in the uterus is called an embryo.
Foetus- An unborn baby in the uterus at the stage when all the body parts can be identified.) d)
Can the process of a child changing into an adult be called metamorphosis?
(Hint: No, the process of a child changing into an adult cannot be called metamorphosis because the
basic body structure does not change.)
b) Why is it that dogs always produce several puppies whereas human beings usually produce only one
child at a time? (Hint: Dogs produce more than one egg at a time. Hence, more puppies are born to
them at the same time. Whereas humans usually produce one egg at a time, hence produce only one
child at a time)
c)Under what circumstances can twins be born in humans? (Hint: Twins are born when two eggs are
produced and fertilised by two sperms or when a single zygote splits and forms two embryos)
2) a) Why are not all animals oviparous? Does vivipary offer any advantage to organisms? (Hint: -All animals are not oviparous because being viviparous offer certain advantages over oviparous animals. Oviparous animals are those animals that reproduce by laying eggs and viviparous animals are those animals which reproduce by giving birth directly to the baby. After laying eggs, the mother needs to take care of the egg like by hatching it and saving it from predators. But in the case of a viviparous baby develop inside the mother's womb and take nutrients from
the mother and she does not worry about predators also.)
d) List the functions of the jelly cover around the frog’s egg. (Hint: There are lots of functions that the jelly in a frog's egg can provide. Firstly, it helps to keep the eggs together, or else they may float with water. Secondly, it acts as a protective covering so that the eggs do not die. Thirdly it protects the egg from any kind of injury.)
