In autotrophs, water is transported through:

The cells in our blood which destroy disease-causing germs, are :

The wave of expansion of an artery when blood is forced into it is called :

An animal having double circulation in a three-chambered heart is:

The transport system in plants consists of two kinds of tissues X and Y. The tissue X is made up of living cells and consists of two components A and B. The component A has tiny pores in its end walls and contains only cytoplasm but no nucleus. On the other hand, component B has cytoplasm as well as nucleus. The tissue Y is made up of dead cells and consists of two components C and D. The component C has open ends whereas component D does not have open ends. In flowering plants, either only C or both C and D transport water but D is the only water conducting tissue in non-flowering plants.

(a) What is (i) tissue X (ii) component A, and (iii) component B ?

(b) What is (i) tissue Y (ii) component C, and (iii) component D ?