Chapter 3 - anatomy and nervous system

Question 1

Describe neurons and its three major parts:

Answer 1

neurons: the basic information processing unit of the nervous system. Brain contains about 100 billion neurons.
1. dendrites
2. cell body
3. axon
A:

Question 2

What are dendrites?

Answer 2

receiving end for neurons.

Question 3

What is cell body?

Answer 3

central part of neurons.

Question 4

What is the axon?

Answer 4

sending end for neurons.

Question 5

What is the difference between sensory and motor neurons?

Answer 5

sensory neurons: sends info from organs to brain/spinal cord.
motor neurons: sends info from brain/spinal cord to organs.

Question 6

What is function of glial cells?

Answer 6

the support cells of the nervous system.

Question 7

What is the difference between conduction and transmission?

Answer 7

conduction: movement of electric signals inside a neuron.
transmission: movement of electric signals between neurons over synapse.

Question 8

What is the difference between resting potential and action potential?

Answer 8

resting potential: negative charge; electric charge between inside/outside of neuron’s cell membrane.

action potential: positive charge; electric charge along length of neuron’s axon to a synapse.

Question 9

What is the myelin sheath? What is its function?

Answer 9

myelin sheath: a fatty substance made up of specialized glial cells that insulates the axon and helps impulses travel down the axon more swiftly and efficiently.

Question 10

What illness involves the deterioration of the myelin sheath?

Answer 10

multiple sclerosis.

Question 11

What is the synapse?

Answer 11

a space or junction where an axon of one neuron sends a signal to the dendrite of another neuron.

Question 12

What are neurotransmitters?

Answer 12

are chemicals that carry signals from the terminal buttons (axon terminals) of the sending neuron across the synapse to the dendrite of the receiving neuron.

Question 13

What are receptors?

Answer 13

specialized sites (channels) on the membrane of dendrites or cell bodies that respond to specific neurotransmitters.

Question 14

What is the lock-and-key system?

Answer 14

where only certain neurotransmitters can activate certain receptors.

Question 15

What is acetylcholine?

Answer 15

a neurotransmitter involved in a number of functions, including motor control.

Question 16

What is dopamine?

Answer 16

a neurotransmitter that regulates fine motor control, motivation, pleasure, emotional arousal, controlled cognition, and reward.

Question 17

What is serotonin?

Answer 17

a neurotransmitter involved in the regulation of sleep and wakefulness, appetite, inhibition, mood, and aggressive behavior.

Question 18

What is gamma-aminobutyric acid (GABA)?

Answer 18

the primary inhibitory neurotransmitter in the brain.

Malfunctions linked to anxiety disorders.

Question 19

What’s the difference between agonist and antagonist?

Answer 19

agonists: mimic the effects of a neurotransmitter.
antagonist: block a particular receptor, thus blocking the function of a neurotransmitter.