⭐ UNIT 3: DNA & Genetics

9th grade Biology FHS

What is DNA?

A molecule that carries genetic information.

Where is DNA found?

In the nucleus (for eukaryotes).

What is a gene?

A section of DNA that codes for a trait.

What is a chromosome?

Tightly coiled DNA.

How many chromosomes do humans have?

46 total (23 pairs).

What is the shape of DNA?

Double helix (twisted ladder).

What are the DNA base pairs?

A with T, C with G.

What makes individuals different?

Different order of bases in their DNA.

What is a mutation?

A change in the DNA sequence.

What makes a mutation harmful?

It lowers survival or causes a disease.

What makes a mutation neutral?

It has no effect on survival.

What makes a mutation beneficial?

It improves survival (rare).

What is a trait?

A characteristic you inherit (eye color, hair color).

What is heredity?

Passing traits from parents to offspring.

What is a protein?

A molecule DNA codes for that builds/controls your body.

Why is DNA important?

It controls all traits and cell functions.