Final Flashcards
(32 cards)
Mammals have circadian rhythms ____.
for a variety of activities, including sleep
Based on research it has been determined that the human circadian rhythm appears to be
just over 24 hours
Animals produce endogenous circadian rhythms that last
about a day
A Zeitgeber is a
an environmental cue that resets a biological clock
T/F alternation between wakefulness and sleep depends completely on stimuli in the environment
False
If suprachiasmatic nucleus neurons are disconnected from the rest of the brain, they:
continue to produce activity that follows a circadian rhythm
The SCN is located just above the
optic chiasm
When do the secretions of melatonin begin?
a couple of hours before a person falls asleep
A small branch of the optic nerve known as the ____ path extends directly from the retina to the SCN
retinohypthalamic
The circadian rhythm is reset by input from special ganglion cells in the retina. These ganglion cells are unusual in that they ____.
respond directly to light but respond very slowly
The PER and TIM proteins accumulate during the day until they cause sleepiness. What prevents them from continuing to accumulate at night?
when the proteins reach a high level they turn off the genes that produce them
During REM sleep, the EEG shows
irregular low voltage fast waves
For a normal person, about how long does a cycle of sleep (from stage 1 to slow-wave sleep and back again) last?
90 min
During sleep, what happens in the brain?
increased firing by GABA neurons
Research found that during REM sleep, activity ____.
increased ion both pons and limbic system
One part of the reticular formation that contributes to cortical arousal is known as the ____.
pontomesencephalon
Eugino has a large number of PGO waves. He is likely ___.
in NREM sleep
A decrease in the amount of sleep most likely to affect the performance of migratory bird during ____.
seasons other than migration
A recent hypothesis proposed that the role of REM is ____.
to shake the eyeballs back and forth in order to get sufficient oxygen to the corneas of the eyes
Male sexual behavior depends heavily on neurons in the medial preoptic area of the hypothalamus releasing which substance?
dopamine
Who would probably develop as an intersex?
a genetic female exposed to more testosterone than normal during early development
Congenital adrenal hyperplasia (CAH) occurs because the adrenal gland releases ____.
too little cortisol
If a female rat is exposed to highly stressful experiences late in pregnancy, what happens to the sexual development of her offspring?
the genetic males become responsive to male partners
Which claim is most consistent with the evolutionary perspective of sleep?
the function of sleep is similar to hibernation
