STD 11 - 9. Biomolecules — BIOLOGY STD 11 Science — Question

$(i)$ Ascidia'               $(ii)$ Cockroach

$(iii)$ Earthworm         $(iv)$ Prawn

$(v)$ Silver fish          $(vi)$ Snail

$(vii)$ Squid

$(a)$ Contraction of diaphragm

$(b)$ Contraction of external inter-costal muscles

$(c)$ Pulmonary volume decreases

$(d)$ Intra pulmonary pressure increases

$(i)$ Unicellular, colonial, filamentous, symbiotic or free living.

$(ii)$ The colonies are surrounded by a gelatinous sheath.

$(iii)$ Some can fix atmospheric nitrogen in specialized cells called heterocysts.

$(iv)$ They often form blooms in water bodies.