Circadian Rhythmns

Question 0

what are the characteristics of rhythm

Answer 0

period
frequency
amplitude
phase

Question 1

chronobiology

Answer 1

study of biological clocks and associated rhythms

Question 2

rhythm period

Answer 2

length of time to complete one cycle of rhythm

Question 3

rhythm frequency

Answer 3

number of completed cycles/Time

Question 4

rhythm amlitude

Answer 4

amount of change above and below rhythm average

Question 5

rhythm phase

Answer 5

point on the rhythm relative to some objective point during the cycle

Question 6

Circadian Rhythms: when are the cycles?

name behaviors

Answer 6

day/night

behaviors: sex, learning, parenting, aggression, social behaviors

Question 7

circatidal rhythm

Answer 7

varies with 12.4 hour tide,

behaviors such as burrowing and feeding

Question 8

Circalunar rhythm

Answer 8

varies with phases of the moon, present in limited species

Question 9

Circannual rhythm

Answer 9

varies with season

behaviors such as migration and hibernation

Question 10

Why are biological rhythms necessary

Answer 10

synchronizes animal behavior with environment, allows to preparation for predictable events

also, synchronizes internal physiological and biochemical processes to promote efficient functioning

Question 11

diurnal
nocturnal
crepuscular
why/how?

Answer 11

day
night
dawn/dusk
underyling differences in physiology

Question 12

Name two ways rhythms are controlled and describe each

Answer 12

exogenously controlled rhythms are factors outside of the organism such as light

endogenously controlled rhythms are within the organism such as whatever, melatonin

Question 13

isolation experiments…

Answer 13

determine endogenous vs exogenous rhythm control

Question 14

heliotropic plant experiment

Answer 14

leaves open in day close at night
persisted when removed from light
free runnings rhythms deviated slightly from baseline 24hr rhythm in absence of cuesq

Question 15

Zeitgebers!

Answer 15

potent environmental cue such as light

Question 16

Entrainment

Answer 16

Process of synchronizing biological rhythms to zeitgebers

Question 17

free running

Answer 17

rhythms not synchronized to environmental cue

Question 18

need to study graphs and pictures from

Answer 18

chapter about circadian rhythms

Question 19

Where are physiological oscillators located in:
amphibians
fish, bird, reptile
mammal

Answer 19

eyes of amphibians
pinneal gland of F, B, R
Suprachiasmatic Nucleus of hypothalamus mammals

Question 20

study SCN transplantation

Answer 20

Know that Petri dish SCN cells continue to demonstrate circadian rhythms

know about SCN transplantation

Question 21

T/F melatonin is effected by/effects seasonal behavior

Answer 21

T

Question 22

Where do mammalian pacemaker cells of circadian rhythms exist

Answer 22

SCN

Question 23

How is light, received by the photoreceptors of eye, transmitted to the SCN

Answer 23

via the RHT, retinohypothalamic tract

Question 24

Name an indirect pathway by which photic info* is transmitted from to the SCN

by which neurochemical?

Answer 24

geniculohypothalamic tract GHT

NPY

Question 25

Name some neuropeptides important to the SCN

Answer 25

NPY, vasopressin, somatostatin

Question 26

How many output pathways from SCN

Answer 26

probably hundreds

Question 27

what do you call two proteins stuck together

Answer 27

dimer

Question 28

Follow pathway from SCN to melatonin production

Answer 28

SNN to Paraventricular nucleus
PVN to medial forebrain bundle
MFB to superior cervical ganglion
SCG sends NE axons to pineal gland
pineal gland produces melatonin

Question 29

What are some effects of melatonin

Answer 29

affects daily rhythms and effected by length of day

Question 30

describe how “the clock tells time”

hint= dimer, proteins, genes

Answer 30

Clock and cycle proteins bind to form a dimer
the dimer promotes transcription of two genes:
period (per) and cryptochrome (cry)
The per/cry protein complex enters the nucleus and inhibits the transcription of per and cry genes
no new proteins are made until the first set degrades, approximately 24 hrs

Question 31

what is photoperiodism and what does it depend on and what does it need

Answer 31

use of day length to time annual cycles

it is dependent on the effects of light on melatonin production

Question 32

duration of melatonin secretion tells mammals info about what

Answer 32

length of day
brief duration of melatonin=short night
long duration of melatonin= long night

Question 33

What do EEGs measure?

Descibe the patterns

Answer 33

EPSPS near surface of brain
alpha
beta Need to find Hz levels that correspond to each of
theta these levels
gamma
delta

Question 34

_____ activates the cortex and wakes the forebrain from sleep

Answer 34

reticular formation

Question 35

what does the pons do for sleep

Answer 35

inhibits motorneurons during rem