Chapter 2

Question 1

Neuron

Answer 1

Receive information and transmit it to other cells

Question 2

Membrane

Answer 2

• Surface of the cell
• separates the inside of the cell form the outside
• Composed of two layers of fat molecules that are free to flow around one another

Question 3

Nucleus

Answer 3

the structure that contains the chromosomes

Question 4

Mitochondrion (pl: mitochondria)

Answer 4

the structure that performs metabolic activities, providing the energy that the cell requires for all other activities.

Question 5

Ribosomes

Answer 5

the sites at which the cell synthesizes new protein molecules
(some float freely while others are attached to the endoplasmic reticulum)

Question 6

What do proteins do?

Answer 6

provide building materials for the cell and facilitate various chemical reactions

Question 7

Endoplasmic Reticulum

Answer 7

a network of thin tubes that transport newly synthesized proteins to other locations

Question 8

What makes neurons unique?

Answer 8

their shape which varies enormously from one neuron to another

Question 9

What are the components of a neuron?

Answer 9

dendrites, a soma (cell body), an axon, and presynaptic terminals

Question 10

Motor Neuron

Answer 10

It’s soma is located in the spinal cord

• receives excitation from other neurons through its dendrites
• conducts impulses along its axon to a muscle

Question 11

Sensory Neuron

Answer 11

specialized at one end to be highly sensitive to a particular type of stimulation such as light, sound, or touch

Question 12

Dendrites

Answer 12

• branching fibers that get narrower near their ends
• surface is lined with synaptic receptors which receive information from other neurons
• greater surface=more information it can receive
• may contain dendritic spines

Question 13

Dendritic Spines

Answer 13

short outgrowths that increase the surface area available for synapes

Question 14

Soma (cell body)

Answer 14

• contains the nucleus, ribosomes, and mitochondira
• most metabolic work of the neuron occurs here
• size in diamter .005-0.1 mm
• covered with synapses on its surface

Question 15

Axon

Answer 15

• thin fiber of constant diameter, usually longer than dendrites
• the neuron’s information sender, conveying an impulse toward other neurons or an organ or muscle
• covered in a myelin sheath with Nodes of Ranvier
• many branches that have a presynaptic terminal on the end

Question 16

Myelin Sheath

Answer 16

insulting material that covers an axon

Question 17

Nodes of Ranvier

Answer 17

interruptions along the axon

Question 18

Presynaptic Terminal

Answer 18

• bulb at the end of the axon branch (end bulb or bouton)

- point from which the axon releases chemicals that cross through the junction between one neuron and the next

Question 19

Afferent Axon

Answer 19

brings information into a structure (admit)

Question 20

Efferent Axon

Answer 20

carries information away from a structure (exit)

Question 21

Interneuron or Intrinsic Neuron

Answer 21

if the cell’s dendrites and axon are entirely contained within a single structure