Podcast
Questions and Answers
Which hormone shows maximal secretion between 6-8 a.m.?
Which hormone shows maximal secretion between 6-8 a.m.?
In which rhythm does the hormone prolactin show maximal secretion 1 hour after going to sleep?
In which rhythm does the hormone prolactin show maximal secretion 1 hour after going to sleep?
During which stage of development is gonadotrophin released mainly at night?
During which stage of development is gonadotrophin released mainly at night?
What is a potential adverse side effect of high doses of the sleeping aid marketed as a 'Health Food Additive'?
What is a potential adverse side effect of high doses of the sleeping aid marketed as a 'Health Food Additive'?
Signup and view all the answers
What type of regulation is involved in the control of synthesis and secretion of hormones?
What type of regulation is involved in the control of synthesis and secretion of hormones?
Signup and view all the answers
What are the possible adverse events associated with the sleeping aid in individuals with seizures?
What are the possible adverse events associated with the sleeping aid in individuals with seizures?
Signup and view all the answers
What is the main function of CLOCK and BMAL in the molecular clock?
What is the main function of CLOCK and BMAL in the molecular clock?
Signup and view all the answers
What is the role of the suprachiasmatic nucleus (SCN) in regulating circadian rhythms?
What is the role of the suprachiasmatic nucleus (SCN) in regulating circadian rhythms?
Signup and view all the answers
Which cells are primarily responsible for entraining the molecular clock through sensitivity to light?
Which cells are primarily responsible for entraining the molecular clock through sensitivity to light?
Signup and view all the answers
What is the function of the retinohypothalamic tract in relation to the molecular clock?
What is the function of the retinohypothalamic tract in relation to the molecular clock?
Signup and view all the answers
Which gland acts as a link between external photoperiod and internal milieu?
Which gland acts as a link between external photoperiod and internal milieu?
Signup and view all the answers
What is the major hormone secreted by the pineal gland that contributes to circadian rhythms?
What is the major hormone secreted by the pineal gland that contributes to circadian rhythms?
Signup and view all the answers
How do photosensitive ganglion cells contribute to entrainment of the molecular clock?
How do photosensitive ganglion cells contribute to entrainment of the molecular clock?
Signup and view all the answers
What is the main Zeitgeber that entrains the molecular clock if no external cues are present?
What is the main Zeitgeber that entrains the molecular clock if no external cues are present?
Signup and view all the answers
What is the role of peripheral clocks in regulating circadian rhythms?
What is the role of peripheral clocks in regulating circadian rhythms?
Signup and view all the answers
Study Notes
Hormone Secretion Patterns
- Cortisol shows maximal secretion between 6-8 a.m.
- Prolactin shows maximal secretion in an ultradian rhythm, with peaks 1 hour after going to sleep.
Developmental Regulation of Hormones
- Gonadotrophin is released mainly at night during the prepubertal stage of development.
Sleeping Aids and Adverse Effects
- High doses of the sleeping aid marketed as a 'Health Food Additive' can cause adverse side effects.
- In individuals with seizures, the sleeping aid can cause seizures.
Regulation of Hormone Synthesis and Secretion
- The control of synthesis and secretion of hormones involves negative feedback regulation.
Molecular Clock and Circadian Rhythms
- CLOCK and BMAL are transcription factors that play a key role in the molecular clock, regulating the expression of clock-controlled genes.
- The suprachiasmatic nucleus (SCN) is the master clock that regulates circadian rhythms, responding to light and dark signals.
- Intraparenchymal photosensitive ganglion cells in the retina are primarily responsible for entraining the molecular clock through sensitivity to light.
- The retinohypothalamic tract transmits light information from the retina to the SCN, regulating the molecular clock.
Pineal Gland and Circadian Rhythms
- The pineal gland acts as a link between external photoperiod and internal milieu, regulating circadian rhythms.
- Melatonin is the major hormone secreted by the pineal gland that contributes to circadian rhythms.
Entrainment of the Molecular Clock
- Photosensitive ganglion cells contribute to entrainment of the molecular clock by detecting light and transmitting signals to the SCN.
- In the absence of external cues, the molecular clock is entrained by an intrinsic circadian rhythm, with a period of approximately 24 hours.
Peripheral Clocks
- Peripheral clocks in peripheral tissues, such as the liver and pancreas, play a key role in regulating circadian rhythms, responding to signals from the SCN.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge about biological rhythms, hormones, receptors, and the work of Jean-Jacques Mairan in the 18th century. Explore the concepts of plant movements, cyclicality, and endogenous mechanisms.
