NEET Practice Questions (MCQs) with Answers & Solutions

Cnidoblasts are specialized cells found in Cnidarians that contain stinging organelles called nematocysts. They play a role in anchorage, defense against predators, and capturing prey. Thus, all of the given options (anchorage, defense, capture) are correct.

The gastro-vascular cavity is a central digestive compartment found in Cnidarians like Hydra. It serves both digestive and circulatory functions. Earthworms, liver flukes, and Ascaris do not possess a gastro-vascular cavity. Therefore, the correct answer is Hydra.

Pleurobrachia, a genus of comb jellies, possesses 8 external rows of ciliated comb plates, which they use for locomotion. These comb plates are one of the distinguishing features of ctenophores.

Flame cells are specialized excretory cells found in platyhelminthes (flatworms). They function in osmoregulation and excretion, helping to remove waste materials from the organism's body.

The pseudocoelomate among the given options is Aschelminthes. Pseudocoelomates are animals that have a body cavity that is not entirely lined by mesoderm. Aschelminthes, also known as nematodes or roundworms, possess this type of body cavity. Porifera, Annelida, and Mollusca do not have a pseudocoelom; Porifera are characterized by having no true body cavity, Annelida are coelomates with a true coelom, and Mollusca are also coelomates.

To correctly match the pairs:

Ascaris (p) is a Roundworm, so it matches with (ii).

Wuchereria (q) is a Filaria worm, so it matches with (iv).

Ancylostoma (r) is a Hookworm, so it matches with (i).

Tapeworm (s) is a Flatworm, so it matches with (iii).

Thus, the correct matching is:

p - (ii), q - (iv), r - (i), s - (iii)

In annelids, the neural system consists of paired ganglia connected by lateral nerves to a double ventral nerve cord. This ventral nerve cord runs along the length of the body and is a characteristic feature of the annelid nervous system.

Parapodia are paired, fleshy protrusions found in some annelids (e.g., polychaetes) that aid in movement and swimming. They function as lateral paddles, helping the organism to swim through water.

Arthropoda is the largest phylum in the animal kingdom. It includes insects, arachnids, myriapods, and crustaceans, which together comprise the most diverse and numerous group of animals on Earth.