Lesson HST:N2-1
CD HST.  Health Science Technology
Unit N.  Human Structure and Function: The Nervous System
Problem Area 2.  Identify the Basic Unit of the Nervous System
Lesson 1.  Neurons

1. What is a function of myelin?

a. allows impulses to be passed along an axon at a rate that is hundreds of times faster than impulses passed along axons that are not covered with myelin

b. contains the usual cellular organelles (endoplasmic reticulum, Nissl Bodies, Golgi bodies, mitochondria, and pigment inclusions), with the exception of centrioles, which are necessary for mitosis

c. provide a large surface area for receipt of stimuli including heat, cold, touch, smell, hearing, vision, balance, hunger, and thirst

d. serves to inhibit nerve impulses to other neurons, muscles, or glands

Answer: a

2. A _____________ is a short, branching extension that carries electrical signals toward the cell body.

a. dendrite

b. dentate

c. director

d. dolomite

Answer: a

3. What have a long dendrite and a short axon and are sometimes referred to as afferent neurons?

a. collateral nerons

b. internerons

c. motor neurons

d. sensory neurons

Answer: d

4. What is the point of junction where an impulse is passed between two neurons?

a. end bulb

b. receptor

c. synapse

d. terminal knob

Answer: c

5. Information is able to cross the synaptic cleft in the form of a chemical known as _________.

a. a neurotransmitter

b. a presynaptic cleft

c. an efferent

d. an electrical synapse

Answer: a