A. Answer the following questions in short:
1. Explain the importance of reproduction in organisms.
2. Describe the process of fertilisation in human beings.
3. Give two differences between a zygote and a foetus.
4. Define asexual reproduction. Describe two methods of asexual reproduction in animals.
5. In which female reproductive organ does the embryo get embedded?
6. What is metamorphosis? Give examples.
7. Differentiate between internal fertilisation and external fertilisation.
8. Why do you think it is necessary for frogs and fish to lay so many eggs?
9. What do you think would have happened if humans also give birth to a large number of babies at the same time?
B. Tick (✓) the correct option:
1. Internal fertilisation occurs:
(a) in female body
(b) outside female body
(c) in male body
(d) outside male body
2. A tadpole develops into an adult frog by the process of:
(a) fertilisation
(b) metamorphosis
(c) embedding
(d) budding
3. The number of nuclei present in a zygote is:
(a) none
(b) one
(c) two
(d) four
4. Egg producing animals such as birds are called:
a) viviparous
(b) oviparous
(c) hermaphrodite
(d) unisexual
C. State True or False:
1. Oviparous animals give birth to young ones. ………………
2. Each sperm is a single cell. ………………..
3. External fertilisation takes place in frog. …………….
4. A new human individual develops from a cell called gamete. ……………
5. Egg laid after fertilisation is made up of a single cell. ………………….
6. Amoeba reproduces by budding. ……………….
7. Fertilisation is necessary even in asexual reproduction. ………………….
8. Binary fission is a method of asexual reproduction. ………………..
9. A zygote is formed as a result of fertilisation. ………………
10. An embryo is made up of a single cell. ……………….
D. Fill in the blanks:
1. The process of ………………… ensure continuity of life.
2. …………………….. are unisexual.
3. The animals that produce only one kind of gametes are known as ………………… .
4. The cells involved in the sexual reproduction are called …………….. .
5. The fusion product of sperm and ovum is known as ……………….. .
E. Visit a poultry farm. Talk to the manager of the farm and try to find out the answers to the following:
1. What are layers and broilers in a poultry farm?
2. Do hens lay unfertilised eggs?
3. How can you obtain fertilised and unfertilised eggs?
4. Are the eggs that we get in the stores fertilised or unfertilised?
5. Can you consume fertilised eggs?
6. Is there any difference in the nutritional value of fertilised and unfertilised eggs?
F. Try to name some of the young ones by completing the table:
G. Complete the crossword puzzle using the clues given below:
Across (→)
1. The process of the fusion of the gametes.
6. The type of fertilisation in hen.
7. The term used for bulges observed on the sides of the body of hydra.
8. Eggs are produced here.
Down (↓)
2. Sperms are produced in these male reproductive organs.
3. Another term for the fertilised egg.
4. These animals lay eggs.
5. A type of fission in amoeba.