30. Overview of Animals

Which of the listed characteristics is shared by plants, fungi, and animals?

Animals probably evolved from colonial protists. How do animals differ from these protist ancestors?

Many young animals are __________, a sexually immature form that is morphologically distinct from the adult stage. These young animals undergo __________ to become __________, which resemble adults but are not yet sexually mature.

Which of the following groups does not exhibit bilateral symmetry?

Which of the following is a characteristic of cnidarians?

In the embryo of a shark, ectoderm gives rise to __________; mesoderm gives rise to __________; endoderm gives rise to __________.

Which of the following is the defining characteristic of the clade Ecdysozoa for which this group is named?

Unlike other animals, sponges __________.

Which of the following is characteristic of protostomes?

All animals with bilateral symmetry have __________ germ layer(s).

A true coelom is __________.

One of the primary developmental/anatomical characteristics distinguishing the major animal phyla is the condition of the body cavity. A pseudocoelomate animal is one in which the body cavity is __________.

The presence of a coelom is advantageous because __________.

Indeterminate cleavage produces embryonic cells that __________.

The zygotes of many protostomes undergo __________ cleavage and __________ cleavage.

An animal with a true coelom that has __________ cleavage must be a(n) __________.

Which of the following is a trait shared by protostomes and deuterostomes?

Name two phyla of animals that are radially symmetric and two that are bilaterally symmetric. How do the general lifestyles of radial and bilateral animals differ?

The table below lists the common names of the nine animal phyla surveyed in this chapter. For each phylum, list the key characteristics and some representatives.

Which synapomorphy (shared, derived trait) distinguishes animals as a monophyletic group, distinct from choanoflagellates? a. multicellularity b. coloniality c. heterotrophy d. movement

Identify the pattern of embryonic development shown in each drawing below and name the phylum (or phyla) that exhibit this pattern.

Which of the following was probably the least important factor in bringing about the Cambrian explosion? a. the emergence of predator-prey relationships b. an increase in the concentration of atmospheric oxygen c. the movement of animals onto land d. the origin of Hox genes

Bilateral symmetry in animals is best correlated with a. an ability to see equally in all directions. b. the presence of a skeleton. c. motility and active predation and escape. d. adaptation to terrestrial environments.

Which of the following combinations of phylum and description is correct? (A) Echinodermata—radial symmetry as a larva, coelom (B) Nematoda—roundworms, internal skeleton (C) Platyhelminthes—flatworms, gastrovascular cavity, no body cavity (D) Porifera—gastrovascular cavity, coelom

Which of the following animal groups does not have tissues derived from mesoderm? a. annelids b. echinoderms c. cnidarians d. flatworms