Question

Which of the following statements is TRUE regarding sea anemones?

	None of the answer options is correct.
	Sponges—not sea anemones—possess what is considered to be the “simplest” nervous system found in animals.
	Because sea anemones are “simple” organisms, these animals only possess motor neurons; sensory neurons or interneurons are never found in sea anemones.
	Although sea anemones possess “net-like” nervous systems, these animals have brains located at their bases (near where they would attach to rocks).
	Although sea anemones lack definitive brains, they do possess ganglia that serve a similar function to the paired ganglia of flatworms.

2.

Some people have low levels of calcium circulating in the blood, a condition known as hypocalcemia. While for many this disorder has little to no effect, for some it can be life-threatening. How could low levels of calcium harm an individual?

	Low levels of calcium would not have any effect on synaptic transmission.
	Low levels of calcium would cause sustained depolarization of the presynaptic cell.
	Low levels of calcium would result in fewer signals sent between the pre- and postsynaptic cell.

3.

Cephalization is: the

	All of these choices are correct.
	development of a brain within the head of an animal.
	concentration of sensory organs within the head end of an animal.
	development of a “head end” in an organism.

4.

Which of the following are TRUE about the resting membrane potential? (Select all that apply.)

	It results from voltage-gated sodium channels remaining open for long periods of time.
	It results from K+ ions diffusing out of the cell.
	It results from the sodium-potassium pump moving more Na+ ions out of the cell than K+ ions into the cell.

5.

Afferent and efferent neurons differ in:

	their size.
	the directionality of the information they send.
	their pattern of myelination.

6.

A neuron that responds to the environment is a(n):

	interneuron.
	homeostatic neuron.
	motor neuron.
	sensory neuron.

7.

Which of the following is NOT the role of an interneuron?

	stimulating a muscle to contract
	conveying information from the internal environment of an animal
	relaying information from sensory to motor neurons
	maintaining homeostasis

8.

Where are postsynaptic cell receptor proteins synthesized?

	the Golgi apparatus
	the lysosome
	the cytoplasm
	the rough endoplasmic reticulum

9.

Inhibition of the flexor muscle during the knee-extension reflex is an example of:

	homeostasis.
	reciprocal inhibition.
	negative feedback.
	All of these choices are correct.

10.

What type of cells produce myelin for sensory neurons?

	pyramidal neurons
	glial cells
	melanocytes
	astrocytes