Chromosomes and Karyotypes (Unit 5)

What are chromosomes made up of?

Chromatin, which consists of DNA and proteins.

What binds sister chromatids together?

A centromere

How many chromosome pairs do humans have?

Humans have 23 pairs of chromosomes.

What are autosomes?

Chromosomes that are not related to biological sex

What are sex chromosomes?

The last two chromosomes that determine biological sex.

What is a karyotype?

An image of all chromosomes,

When are karyotypes taken?

a cell in mitosis at or before metaphase

Why are karyotypes taken at or before metaphase?

The chromosomes are tightly packed together.

How many chromosomes do gametes have?

Gametes have half the number of chromosomes as body cells

Are gametes haploids or diploids?

haploids

What happens when a sperm and egg cell combine?

They form a fertilized egg (zygote), which is a diploid.

What is a zygote?

A diploid cell formed from the fertilization of an egg by a sperm.

How can a karyotype help in identifying genetic disorders?

It shows any missing chromosomes, which can indicate genetic disorders.

How many pairs of autosomes do humans have?

22 pairs

What happens when 1 chromosome is duplicated?

There is still 1 chromosome, but now 2 sister chromatids.