Exam 30: Animal Origins and the Evolution of Body Plans

Fluid-filled internal body cavities function as hydrostatic skeletons that facilitate movement.Which animal has a body cavity that functions as a hydrostatic skeleton?

Refer to the table. The character states of characters 25 and 27 are shared and derived for which of the following clades?

How do nematocysts help protect some cnidarians?

Which statement best distinguishes herbivores from predators?

Why is bilateral symmetry most beneficial for mobile organisms?

The probable ancestor of the animal clade resembled modern _______, which have similarities to modern _______.

Which statement about sponges is false?

A larva is

Which of the following features is a synapomorphy of the bilaterians?

Imagine you are a scientist who has discovered a new organism on a scientific expedition.What specific characteristics would you investigate in order to determine if it is an animal?

Most parasite species have a

A major threat to coral reefs is overgrowth of algae that eventually smother the corals.This overgrowth results from

A radially symmetrical, sessile animal that possesses some sort of straining device would most likely be a(n)

The overall shape of an animal can be described by its

Refer to the table, which compares 27 amino acid positions for ten different species. Which of the following characters have shared, derived character states for deuterostomes?

Which of the following is/are not an adaptation for predatory feeding?

An animal, such as a snake, that waits in one spot for food is an example of a(n)

Refer to the figure. Which form of the insect (cecropia moth) shown is best adapted for dispersal and reproduction?

Which animal group lacks body symmetry?

Suppose that you obtain a sample of seawater and observe it under a microscope.You identify some single-celled structures that you think may be animals but are unable to ascertain whether they are developmental stages or adults.Develop a hypothesis to determine the stage of the life cycle you are observing, and identify three characteristics you would examine to support your hypothesis.