Exam 17: The Evolution of Animals

The figure shows a simple worm. Bilateral symmetry and a highly branched gastrovascular cavity all suggest that the worm is a(n)________.

On a hike in the mountains, you find a stream with a rocky bottom. Many of the rocks are covered in algae. Which type of mollusc is most likely to be found living in this environment?

Where did humans first appear?

The evolutionary tree indicates that ________ anthropoids are most closely related to humans?

Rays are a type of ________.

Most animals are ________ and reproduce ________.

The stationary stage of the cnidarian life cycle is the ________ stage.

All chordates have ________.

What name is given to the food-trapping cells of sponges?

In the image, the segmented body of the worm suggests that it is a(n)________.

All but one of these traits result from evolutionary responses of ancient ancestors to their physical and cultural environment. Choose the EXCEPTION.

The process of biological evolution often allows humans to survive consistent environmental stresses that occur across multiple generations. As humans colonized Earth's diverse environments, they encountered hot, dry areas and decided to settle. What trait likely offered an advantage in this environment?

Unique features of vertebrates include the presence of a(n)________.

The phylogenetic tree indicates that ________ are most closely related to chordates?

Among vertebrates, the unique feature of lampreys and hagfish is the ________.

The common ancestor of all animals is likely to have been a ________.

If researchers are able to determine when HIVs emerged and therefore how transmission of these viruses to humans occurred, how will this help modern medical care?

When the crown of thorns starfish hatches, it has a semitransparent, jellylike appearance with a non-defined shape. As it ages, it grows arms and then spikes, giving rise to its name. This dramatic change in its body features describes the starfish's ________.

The arthropod skeleton is composed of ________.

You are given the task of confirming the categorization of a newly discovered animal that has been tagged as a species of annelid. What evidence would convince you that it is an annelid and not a roundworm or flatworm?