Question

1. What is/are something that annelids like earthworms have that aren’t found in nematodes

A. Chatae

B. Multiple identical body segments

C. An exoskeleton that is periodically shed

D. Both A and B are correct

E. Both B and C are correct

2. You see an animal with two cell layers a single opening leading to a gastrovascular cavity which surrounded by tentacles that is freely swimming. What type of animal is it?

A.Porifera

B.Cnidarian-polyp form

C.Cnidarian-medusa form

D.Mollusc

E.Annelid

3. Which characteristic of birds are shared with at least some other types of dinosaurs

A.Toothless beak

B.feathers

C.Laying eggs

D.Both A and C are correct

E.Both B and C are correct

Answer 1

1.The answer to first question is-

D. Both A and B are correct

Explanation

Annelids are metamerically segmented, by transverse grooves externally and by septa internally. Roundworms or nematodes are not segmented.

Each segment of annelid has paired setae or chaetae that is their locomatory organ.Annelids have numerous of them. Nematodes donot have such organ.

THUS, first and second option are correct.

In case of third option, nematodes do shed their cuticle periodically but this not the case with annelids. Annelids donot shed their cuticle. (exoskeleton)

2. The answer to second question is

C.Cnidarian-medusa form

Explanation-

Cnidarians are the ones who are diloblastic i.e they have two layers of cells,i.e ectoderm and endoderm. They are radially symmetrica with central gastrovascular cavity that communicates with exterior by mouth. Mouth is sorrounded by tentacles.

These are those organisms that shows polymorphism-i.e Polyp form and medusa form. Poly form is sessile and asexual zooid while medusa form is free swimming and sexual zooid.

3.The answer to third question is

E.Both B and C are correct

Explanation- Ancestors of birds were dinosours. Therapods dinosours shows close ancestry with Birds. They had feathers and also laid eggs. Toothless beak is something that was derived in a very slow process caleed evolution by birds. Thus all therapods donot have toothless beak. THus the answer is option E.