unit 2 : biological bases

Question 1

dendrites function

Answer 1

• receives info
• conducts it toward cell body

Question 2

axon function

Answer 2

passes messages through terminal branches to neurons, muscles, or glands

Question 3

myelin sheath

Answer 3

• what axons encased in
• insulates and speeds up impulses

Question 4

action potential

Answer 4

• leads to depolarization
• a neural impulse, brief electrical charge that travels down an axon. makes body ready to move

Question 5

resting potential

Answer 5

• state of a neuron when not sending a signal
• has a slightly negative charge compared to the outside to help get ready to send a signal

Question 6

refractory period

Answer 6

• leads to repolarization
• period of inactivity after a neurons has fired

Question 7

excitatory signal

Answer 7

• increases likelihood of a neuron firing
• makes inside of neuron more positive (depolarization)

Question 8

inhibitory signal

Answer 8

• decreases likelihood of a neuron firing
• makes inside of a neuron more negative (hyperpolarization)

Question 9

all-or-none

Answer 9

• a neurons reaction of either firing or not
• no in between / change in strength

Question 10

communication that occurs between neurons within the synapse

Answer 10

neurotransmitters (chemical messengers) are released into the synapse

Question 11

neurotransmitters

Answer 11

• chemical messengers that cross the synaptic gaps between neurons
• travels to bind to the receptor site on the recieving neuron

Question 12

reuptake

Answer 12

the sending neuron reabsorbs the excess neurotransmitters

Question 13

acetylcholine (Ach)

Answer 13

• neurotransmitters
• increases learning & memory
• ex : you see a runner go by and recall what they were wearing

Question 14

dopamine (DA)

Answer 14

• neurotransmitters
• feel-good actions
• motivation
• coordination & focus
• ex : too little will make you shaky, too much can make you dopey

Question 15

epinephrine (adrenaline)

Answer 15

• neurotransmitters
• fight or flight response
• boosted energy
• increases breathing

ex : a shot from an epi pen gets you ready to fight an allergic reaction

Question 16

norepinephrine (NE)

Answer 16

• neurotransmitters
• controls the body’s fight or flight response
• boosted heart rate
• improved attention & focus

ex : you hear a loud noise behind you at night, your ready to run of defend yourself (epinephrine), norepinephrine makes you alert and focused to respond quick

Question 17

serotonin (SE)

Answer 17

• neurotransmitters
• keeps you calm and happy
• helps you fall asleep
• social behavior

ex : your relaxing on a peaceful day watching the sunset, you feel happy and calm (serotonin)

Question 18

GABA

Answer 18

• neurotransmitters
• reduces anxiety
• promotes relaxation
• improves sleep

ex : you had a stressful day at school but once you get home and start relaxing your anxious thoughts go away (GABA)

Question 19

endorphins

Answer 19

• neurotransmitters
• reduces pain
• relives stress
• boosts mood

ex : runners high, eurphoria

Question 20

agnostic drugs

Answer 20

• a molecule that binds to a receptor site, stimulating a response
• amplifies normal sensations

Question 21

antagonist drugs

Answer 21

• by binding to a receptor site, inhibits / blocks a natural response

ex : botox (blocks muscle contraction)

Question 22

sensory neurons (afferent)

Answer 22

neurons that carry incoming info from sensory receptors to the brain & spinal cord

Question 23

motor neurons (efferent)

Answer 23

neurons that carry outgoing information from the brain & spinal cord to muscles and glands (instructions)

Question 24

interneurons

Answer 24

acts as connectors, relaying signals between sensory & motor neurons