Unit 2 - Biological basis of Behavior

Question 1

Neuron

Answer 1

Nerve cell, building block of the nervous system

Question 2

Cell Body

Answer 2

Part of a neuron that contains the nucleus, the cell’s life support center

Question 3

Dendrites

Answer 3

A neurons often bushy branching extensions that receive and integrate messages, conducting impulses towards the cell body.

Question 4

Axon

Answer 4

The neuron extension that passes messages through its terminal branches to other neurons/muscles or glands

Question 5

Myelin Sheath

Answer 5

Fatty tissue layer segmentally encasing the axons of some neurons, increasing the speed at which impulses move from neuron to neuron

Question 6

Glial Cells

Answer 6

Cells in the nervous system that support, nourish, and protect neurons; play a role in memory, thinking, and learning

Question 7

[action potential] threshold

Answer 7

The level of stimulation required to trigger a neural impulse. about -50 mV

Question 8

[action potential] Refractory period

Answer 8

In neural processing, a brief resting pulse that occurs after a neuron has fires; subsequent action potentials cannot occur until axon returns to resting state.

Question 9

[action potential] All or none response

Answer 9

A neurons reaction of either firing with full strength or not firing at all

Question 10

Synapse

Answer 10

Junction between axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. The tiny gap in between is called the synaptic gap or synaptic cleft.

Question 11

Neurotransmitters

Answer 11

Chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, influencing whether or not the neuron will generate a neural impulse/action potential.

Question 12

Reuptake

Answer 12

When excess neurotransmitters in the synaptic cleft are reabsorbed by the sending neuron.

Question 13

Acetylcholine (ACh)

Answer 13

Function: muscle action, memory, learning
Malfunction: with Alzheimer’s, ACh producing neurons deteriorate

Question 14

Dopamine

Answer 14

Function: Movement, mood, attention
Malfunction: oversupply can lead to schizophrenia, undersupply leads to tremors and decreased mobility

Question 15

Serotonin

Answer 15

Function: Mood, hunger, sleep, arousal
Malfunction: undersupply is linked to depression

Question 16

Norepinephrine

Answer 16

Function: alertness, arousal
Malfunction: undersupply can cause a depressed mood

Question 17

Gamma-aminobutyric acid (GABA)

Answer 17

Function: inhibitory neurotransmitter
Malfunction: undersupply leads to seizures, tremors, insomnia

Question 18

Glutamate

Answer 18

Function: excitatory neurotransmitter, memory
Malfunction: oversupply leads to overstimulation of the brain, causing seizures and migraines

Question 19

Endorphins

Answer 19

“Morphine Within”, natural opiate
Function: influence perception of pain and pleasure
Malfunction: oversupply of opiate drugs may suppress the body’s natural endorphin responses