X-inactivation

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/x-inactivation

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 process name?X-inactivation (Lyonization)
2. What is the primary biological role?Dosage compensation for X-linked genes
3. What is X-inactivation and why does it happen?X-inactivation is a process that turns off one of the two X chromosomes in female mammals to keep gene levels balanced with males. It helps prevent too many proteins from being made.
4. How does a cell decide which X chromosome to turn off?In placental mammals, the choice is random and happens early in development. Each cell picks one X at random, and that decision stays the same in all its future cells.

Dosage Compensation: A biological mechanism that equalizes the expression of sex-linked genes between males and females.
Epigenetics: Heritable changes in gene expression that do not involve alterations to the underlying DNA sequence.
Heterochromatin: Densely packed form of chromatin that is transcriptionally silent.
XIST RNA: A long non-coding RNA transcribed from the X-inactivated chromosome, crucial for its silencing.