A unicellular organism P lives in pond water. The organisms P has no fixed shape, its shape keeps on changing. It moves and catches its prey with the help of organs Q which keep on appearing and disappearing. The organisms P reproduces by a process R. Another organisms S also reproduces by this process. Name P, Q, R and S.

The offspring formed as a result of sexual reproduction exhibits more variations because :

Two very 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. Organisms Y is a tiny animal having tentacles which live in water.

(a) What is organisms X?

(b) Name the process in which X converts sugar into alcohol.

(c) To which class of organism does X belong?

(d) What are organisms Y?

(e) Out of X and Y, which organism is multicellular and which one is unicellular?

The 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 the animal A. The form B then undergoes a change C and gets converted into animal A.

(a) Name (i) animal A and (ii) form B.

(b) What is the change C known as ?

(c) name the breathing organs of A.

(d) What are the breathing organs of B?

X and Y are the two types of animals. The animals like X undergo external fertilization whereas animals like Y undergo internal fertilization. The animals like X lay eggs from which baby animals are hatched. On the other hand, in animals like Y, the young one develops inside the uterus of mother which then gives birth to the baby.

(a) What is the general name of animals like X ?

(b) Give two examples of animals like X ?

(c) What is the general name of animals like Y ?

(d) Write the names if two animals like Y.