Circadian Rhythm Flashcards Preview

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Flashcards in Circadian Rhythm Deck (7):

What are the circadian rhythms?

The natural patterns of physiological and behavioural processes that are timed to a near 24h period


What are the circadian rhythms responsible for?

Responsible for releasing melatonin


Where are the circadian rhythms located?

The biological clock of the hypothalamus
-suprachiasmatic nucleus


Where does melatonin come from and what does it do?

Released from pineal gland

Highly influenced by natural dark/light cycles (inhibited by light) through SNS activation. Light activates limbic core through neurons, and comes back neurally to activate the pineal gland
-indirect control of melatonin release


Where is the pineal gland?

Deep within the brain. but not actually apart of it (like the anterior pituitary)
-release of melatonin is control day the SNS


What is able to trick the melatonin system?

LED light can trick this system b y suppressing melatonin levels.
Viewing LED screens after dark can result in a decreased ability to fall asleep


What are the 9 processes that the biological clock (suprachiasmiatic nucleus) controls?

1. Sleep
2. Food and water intake
3. Urine production
4. Blood Pressure
5. Platelette aggregation
6. White Blood Cell Production
7. Body Temperature Changes
8. Hormone Release
9. Menstrual Cycle