Invertebrate Zoology

In freshwater protozoa like Amoeba, the contractile vacuole collects excess water from the cytoplasm and expels it to prevent the cell from bursting.

The larva breathes through a tube called a siphon that touches the surface of the water and help the mosquitoes to receive air.

The labella is a complex structure consisting of many grooves, called pseudotrachea, which sops up liquids much like a sponge does. Salivary secretions from the labella assist in dissolving and collecting food particles so that they may be more easily taken up by the pseudotrachea.

The pharyngeal dorsal bulb of the earthworm is a true salivary gland. Thus, salivary glands are found on the pharyngeal wall.

The sac-like glands between the 5^th and 6^th abdominal tergites are called stink glands in cockroaches.

Anopheles mosquitoes can be distinguished from other mosquitoes by the palps, which are as long as the proboscis. In males, 3-segmented maxillary palp is present.

When a body is externally and internally divided into segments with serial repetition of atleast some organs, then it is called metamerism. In earthworm, segments are about 100 to 120 in number.

Leech sucks human blood.

Earthworm is called a ‘friend of farmers'.

Correct Answer: closed type with Hb in plasma

Correct Answer: Ovaries mature first in an earthworm.

In males, in the 9th sternum of abdomen, a pair of small, un-jointed anal styles is present. It is absent in females.

Correct Answer: lung

The correct answer is option (2).

A flame cell is a specialized excretory cell found in  flatworms .