DNA

Organisms

All living entities made of cells.

Adult human cells

An adult human contains 50 to 100 trillion cells.

Nucleus

The control center of the cell that contains instructions for cell function.

Chromosomes

Structures within the nucleus made of DNA that carry genetic information.

Human chromosomes

Humans have 46 chromosomes in each cell.

Inheritance of chromosomes

23 chromosomes are inherited from the father and 23 from the mother.

DNA

Deoxyribonucleic acid, the molecule that makes up chromosomes.

Gene

A section of DNA that contains instructions for a specific feature.

Features

Characteristics controlled by genes.

Double helix

The twisted ladder shape of DNA.

Nucleotide

The repeating unit of DNA, made up of sugar, phosphate, and a base.

DNA sides

The sides of DNA are composed of sugar and phosphate.

Nucleotide bases

The chemicals that link the sides of DNA, consisting of adenine, thymine, cytosine, and guanine.

Complementary base-pairing rule

The rule that adenine pairs with thymine and cytosine pairs with guanine in DNA.