Question

Identify (1), (2) and (3) from the given table.

$\begin{array}{ccc}Phylum& Germlayer& Bodycavity\\ \text{(1) \_\_\_\_\_\_\_\_\_\_}& \text{Triploblastic}& \text{No coelom}\\ \text{Nematoda}& \text{Triploblastic}& \text{(2) \_\_\_\_\_\_\_\_\_\_}\\ \text{Annelida}& \text{(3) \_\_\_\_\_\_\_\_}& \text{True coelom}\end{array}$

• A. (1) Porifera, (2) No coelom, (3) Diploblastic
• B. (1) Platyhelminthes, (2) True coelom, (3) Triploblastic
• C. (1) Platyhelminthes, (2) False coelom, (3) Triploblastic
• D. (1) Porifera, (2) False coelom, (3) Triploblastic

Answer 1

The correct option is C (1) Platyhelminthes, (2) False coelom, (3) Triploblastic

In the animal kingdom, different Phylums have different characteristics. For example,
$\bullet$ Phylum Platyhelminthes - The animals belonging to this phylum are triploblastic. They lack body cavity and hence are called acoelomates.
$\bullet$ Phylum Nematoda - The animals belonging to this phylum are triploblastic but they have a body cavity lined by patches of mesoderm. Thus they are considered as psuedocoelomates.
$\bullet$ Phylum Annelida - The animals belonging to this phylum are triploblastic with true body cavity (eucoelomates).