Overview of the Circulatory System

Review Questions

Why are open circulatory systems advantageous to some animals?

  1. They use less metabolic energy.
  2. They help the animal move faster.
  3. They do not need a heart.
  4. They help large insects develop.

Hint:

A

Some animals use diffusion instead of a circulatory system. Examples include:

  1. birds and jellyfish
  2. flatworms and arthropods
  3. mollusks and jellyfish
  4. none of the above

Hint:

D

Blood flow that is directed through the lungs and back to the heart is called ________.

  1. unidirectional circulation
  2. gill circulation
  3. pulmonary circulation
  4. pulmocutaneous circulation

Hint:

C