Suprachiasmatic nucleus

High school (ages 12+)
Human Body

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/suprachiasmatic-nucleus

1. What is the scientific name?
2. What is the location?
3. What is the suprachiasmatic nucleus and why is it called the brain's tiny sleep boss?
4. How does light help the SCN keep our body on time?

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the scientific name?Suprachiasmatic nucleus (SCN)
2. What is the location?Paired nuclei within the anterior hypothalamus, superior to the optic chiasm
3. What is the suprachiasmatic nucleus and why is it called the brain's tiny sleep boss?It is a small part of the brain in the hypothalamus that keeps our body’s 24‑hour clock. It tells us when to wake up and when to sleep.
4. How does light help the SCN keep our body on time?Special eye cells called ipRGCs sense light and send signals to the SCN. The SCN uses those signals to adjust our internal clock.

Circadian Pacemaker: The biological clock that generates and regulates ~24-hour rhythms.
Entrainment: The process by which an internal biological rhythm is synchronized to an external cue, typically the light-dark cycle.
Retinohypothalamic Tract: A neural pathway connecting the retina to the suprachiasmatic nucleus, transmitting light information.
Homeostasis: The tendency of a system to maintain internal stability and balance.