Question 1

Which of the following characteristics is unique to animals and helps distinguish them from plants and fungi?

Accepted Answer

They possess nervous and muscle tissue.

Question 2

During animal development, what is the correct sequence of events from fertilization to the formation of embryonic germ layers?

Accepted Answer

Zygote → Cleavage → Blastula → Gastrulation

Question 3

Which of the following statements about Hox genes is correct?

Accepted Answer

Hox genes regulate the expression of other genes that influence animal morphology.

Question 4

What evidence supports the hypothesis that choanoflagellates are the closest living relatives of animals?

Accepted Answer

Both possess similar genes involved in cell adhesion and signaling.

Question 5

Which of the following best describes the main difference between protostome and deuterostome development?

Accepted Answer

In protostomes, the blastopore becomes the mouth; in deuterostomes, it becomes the anus.

Question 6

Which of the following is a function of a body cavity (coelom) in triploblastic animals?

Accepted Answer

It enables internal organs to grow and move independently of the outer body wall.

Question 7

A fossil from the Ediacaran biota is discovered. Which of the following statements is most likely true about this organism?

Accepted Answer

It may not resemble any living animal or algae.

Question 8

Which of the following is a defining feature of bilaterians that distinguishes them from radially symmetrical animals?

Accepted Answer

Presence of a central nervous system and active movement.

Question 9

Which of the following is true about the Cambrian explosion?

Accepted Answer

It was a period of rapid diversification of animal body plans, especially bilaterians.

Question 10

Which of the following statements about animal phylogeny is correct?

Accepted Answer

Sponges are the sister group to all other animals.

Question 11

Which clade includes animals that undergo ecdysis (molting of an exoskeleton)?

Accepted Answer

Ecdysozoa

Question 12

Which of the following is a real-world example of a hemocoel?

Accepted Answer

The main body cavity in molluscs, where hemolymph circulates.

Question 13

Which of the following best describes diploblastic animals?

Accepted Answer

They have two germ layers: ectoderm and endoderm.

Question 14

Which of the following is a correct statement about the evolutionary history of animals?

Accepted Answer

Arthropods were the first animals to adapt to life on land.

Question 15

Which of the following is a function of the lophophore in lophotrochozoans?

Accepted Answer

Feeding by filtering particles from water

Question 16

Which of the following is a correct pairing of animal group and body symmetry?

Accepted Answer

Sponges – No symmetry

Question 17

Which of the following is a real-world application of understanding animal body cavities in medicine?

Accepted Answer

Predicting how drugs are absorbed in flatworms versus roundworms.

Question 18

Which of the following statements about the fate of the blastopore is correct?

Accepted Answer

In deuterostomes, the blastopore becomes the anus.

Question 19

Which of the following is a correct statement about the Cenozoic era?

Accepted Answer

It followed a mass extinction event and saw the increased diversity of mammals.

An Overview of Animal Diversity

Study Guide - Practice Questions