IB Biology Topic C3.1.11 Modulation of Sleep Patterns by Melatonin Secretion as a Part of Circadian Rhythms Revision Notes (SL/HL)

IB Biology Topic C3.1.11 Modulation of Sleep Patterns by Melatonin Secretion as a Part of Circadian Rhythms Revision Notes (SL/HL) | RevisionDojo

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Melatonin Sets the Body Clock, Rising in Darkness to Trigger Sleep

Definition

Circadian Rhythm

The 24-hour biological cycle that regulates physiological processes, including sleep.

Circadian rhythms are generated inside the body but fine-tuned by external cues like light and temperature.

In humans, the sleep-wake cycle is the most prominent circadian rhythm.

Analogy

Waking naturally as the sun rises, feeling refreshed, is the sleep-wake cycle working smoothly.
That cycle is orchestrated by circadian rhythms, with melatonin in the starring role.

The Pineal Gland Makes Melatonin, the Hormone That Signals Sleep

The pineal gland is a small, pea-shaped gland deep within the brain.
It produces melatonin, a hormone that signals the body when it is time to sleep.
1. Its production is triggered by darkness and inhibited by light.
2. This creates a diurnal pattern: high levels at night and low levels during the day.

Definition

Melatonin

A hormone secreted by the pineal gland that regulates sleep-wake cycles.

Note

Melatonin is called the "hormone of darkness" because its secretion tracks the absence of light.

Falling Light Triggers a Retina-SCN-Pineal Pathway That Releases Melatonin

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Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris.
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum.

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Melatonin Sets the Body Clock, Rising in Darkness to Trigger Sleep

Definition

Circadian Rhythm

The 24-hour biological cycle that regulates physiological processes, including sleep.

Circadian rhythms are generated inside the body but fine-tuned by external cues like light and temperature.

In humans, the sleep-wake cycle is the most prominent circadian rhythm.

Analogy

Waking naturally as the sun rises, feeling refreshed, is the sleep-wake cycle working smoothly.
That cycle is orchestrated by circadian rhythms, with melatonin in the starring role.

The Pineal Gland Makes Melatonin, the Hormone That Signals Sleep

The pineal gland is a small, pea-shaped gland deep within the brain.
It produces melatonin, a hormone that signals the body when it is time to sleep.
1. Its production is triggered by darkness and inhibited by light.
2. This creates a diurnal pattern: high levels at night and low levels during the day.

Definition

Melatonin

A hormone secreted by the pineal gland that regulates sleep-wake cycles.

Note

Melatonin is called the "hormone of darkness" because its secretion tracks the absence of light.

Falling Light Triggers a Retina-SCN-Pineal Pathway That Releases Melatonin

Definition

Paywall

(on a website) an arrangement whereby access is restricted to users who have paid to subscribe to the site.

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Note

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam quis nostrud exercitation.

Excepteur sint occaecat cupidatat non proident

Tip

Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris.
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum.

A - Unity and Diversity9 subtopics

B - Form and Function10 subtopics

C - Interaction and Interdependence9 subtopics

D - Continuity and Change12 subtopics

IB Biology Topic C3.1.11: Modulation of Sleep Patterns by Melatonin Secretion as a Part of Circadian Rhythms Notes

Melatonin Sets the Body Clock, Rising in Darkness to Trigger Sleep

The Pineal Gland Makes Melatonin, the Hormone That Signals Sleep

Falling Light Triggers a Retina-SCN-Pineal Pathway That Releases Melatonin

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

Unlock the rest of this chapter with a free account

Melatonin Sets the Body Clock, Rising in Darkness to Trigger Sleep

The Pineal Gland Makes Melatonin, the Hormone That Signals Sleep

Falling Light Triggers a Retina-SCN-Pineal Pathway That Releases Melatonin

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

Unlock the rest of this chapter with a free account

A - Unity and Diversity9 subtopics

B - Form and Function10 subtopics

C - Interaction and Interdependence9 subtopics

D - Continuity and Change12 subtopics