Suctorial mouth occurs in

MCQ

✓

Answer

Correct option: B.

Leech

b
(b)In leech, a triradiate mouth is found at its bottom. The mouth is used for puncturing the skin of the host. It is also suctorial.

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

$I.$ Ladybirds and dragonflies are used to get rid of aphids and mosquitoes

$II.$ The bacteria Bacillus thuringiensis $(B t)$ are used to control butterfly caterpillars

$III.$ Trichoderma sp. free living fungi, are present in root ecosystems where they act against several plant pathogens

$IV.$ Rhizobium is a symbiotic bacterium that lives in the stem of legumes

Which of the statements given above are correct?

$(i)$ These muscle fibres taper at both ends and do not show striations.

$(ii)$ The wall of internal organs such as the blood vessels, stomach and intestine contain this type of muscle tissue.

$(iii)$ They are 'involuntary' as their function cannot be directly controlled.

Statement I: Lower invertebrates like sponges, coelenterates, flatworms etc exchange O₂ with CO2 by simple diffusion.
Statement II: Amphibians like frogs can respire through their most skin (cutaneous respiration) only.