Question

Match List-I with List-II.
$\begin{array}{cccc}& \text{List-I}& & \text{List-II}\\ \text{(a)}& \text{Metamerism}& \left(i\right)& \text{Coelenterata}\\ \text{(b)}& \text{Canal system}& \left(ii\right)& \text{Ctenophora}\\ \text{(c)}& \text{Comb plates}& \left(iii\right)& \text{Annelida}\\ \text{(d)}& \text{Cnidoblasts}& \left(iv\right)& \text{Porifera}\end{array}$
Choose the correct answer from the options given below.

• A. a - iv, b - i, c - ii, d - iii
• B. a - iii, b -iv, c - ii, d - i
• C. a - iv, b - iii, c - i, d - ii
• D. a - iii, b - iv, c- i, d- ii

Answer 1

The correct option is B a - iii, b -iv, c - ii, d - i

(a) Linear repetition of certain body parts is called metamerism. This is a characteristic feature of animals belonging to the phylum Annelida.

(b) The canal system is a characteristic feature of phylum porifera. The body of the poriferans has several inhalant pores called ostia and a single large exhalent pore called osculum. There is a continuous movement of water from the exterior to the interior of the body. Water enters through the ostia into the spongocoel and goes out through the osculum. This helps in food gathering, respiratory exchange and removal of waste.

(c) Comb plates are a characteristic feature of ctenophores. The ciliated comb plates help in locomotion. Hence, these organisms are also known as comb jellies.

(d) Presence of cnidoblasts is a unique feature of phylum coelenterata. Cnidoblasts or cnidocytes contain stinging capsules or nematocysts. They help in anchorage, defense and capture of prey. Due to the presence of cnidoblasts, coelenterates are also called cnidarians.