Lecture 25

Question 1

What is the function of aldosterone?

Answer 1

steroid hormone = increases sodium reabsorption

Question 2

Which structures of the nephron does it act on?

Answer 2

distal tubule and collecting duct

Question 3

What secretes aldosterone?

Answer 3

adrenal cortex

Question 4

What are the 2 triggers for aldosterone secretion?

Answer 4

increase extracellular potassium | decrease BP

Question 5

What initiates the angiotensin II pathway?

Answer 5

decrease in BP

Question 6

What is the affect of the atrial natriuretic peptide?

Answer 6

increase sodium excretion = opposite of aldosterone

Question 7

What are P-cells?

Answer 7

parietal epithelial cells responsible for sodium reabsorption

Question 8

What is the rectifying channel?

Answer 8

preferential movement/direction of ion flow

Question 9

How can penicillin excretion be delayed?

Answer 9

penicillin and probenecid compete for the same transport system

Question 10

What are the 5 special senses?

Answer 10

vision | hearing | taste | smell | equilibrium

Question 11

What are the 5 somatic senses?

Answer 11

touch | temperature | pain | itch | proprioception

Question 12

What is proprioception?

Answer 12

spatial orientation of body parts

Question 13

What are the 3 kinds of sensory neurons the body uses to get info from the environment?

Answer 13

simple receptors | pacinian corpuscle | hair cells

Question 14

What are simple receptors?

Answer 14

free-nerve endings | sensitive to touch | found on cornea

Question 15

What is the pacinian corpuscle?

Answer 15

enclosed nerve endings with layers of connective tissue

Question 16

What are hair cells?

Answer 16

mechanoreceptors | found in ear

Question 17

What are chemoreceptors?

Answer 17

detects levels of molecules such as O2 and glucose

Question 18

What are mechanoreceptors?

Answer 18

detects movement of air or pressure such as vibrations or cell stretch (osmoreceptors)

Question 19

What are photoreceptors?

Answer 19

detects photons of light

Question 20

What are thermoreceptors?

Answer 20

detects varying degrees of heat

Question 21

What is transduction?

Answer 21

conversion of stimulus energy into info that can be processed by the CNS | via open/close of ion channels and second messenger systems

Question 22

What is two-point discrimination?

Answer 22

when 2 points can be perceived as 2 different stimuli because the secondary neurons are not converging

Question 23

What happens when the secondary sensory neurons converge into 1?

Answer 23

creates a larger receptive field = allows stimuli to be summed up as 1

Question 24

Do all parts of our bodies have 2-point discrimination?

Answer 24

no = different sensory systems throughout the body

Question 25

What are sensory modalities?

Answer 25

different senses such as temp and touch

Question 26

Where is the relay system that all sensory modalities pass through?

Answer 26

thalamus

Question 27

Which sensory system does not pass through the thalamus?

Answer 27

sense of smell = olfactory

Question 28

What does modality mean?

Answer 28

nature of the stimulus (if it is taste or smell)

Question 29

What are the 4 factors that the CNS uses to differentiate between the different senses?

Answer 29

modality | location | intensity | duration

Question 30

What happens if the stimulus continues?

Answer 30

nerve endings will at some point = no longer trigger CNS to relay the info = desensitization to the stimulus

Question 31

What is lateral inhibition?

Answer 31

multiple signals coming in = whichever dominates will inhibit the neighboring secondary neurons

Question 32

What is decussation?

Answer 32

when signals switch from one side of the brain to the other

Question 33

What is homunculus (little man)?

Answer 33

mapping out the somatic sensory cortex and how each part of the cortex reflects that stimulus that comes from the body