DNA

(DNA is a type of nucleic acid!)

Do you remember the four biomolecules?

lipids, protein, carbohydrates and...

•The goal of the cell is to make•Proteins make your traits.

proteins.

Proteins…Proteins…• Such as…

– hemoglobin: transport oxygen

– insulin: hormone; removes sugar from blood

– antibodies: fights infection

– lactase: enzyme; digests milk sugar (lactose)

– collagen: skin, bones, tendons

– keratin: skin, hair, nails

– myosin: muscle contraction

DNA= DeoxyribonucleicAcid

Location in cell: Nucleus

The nucleus contains

chromosomes which

contains DNA. DNA makes your genes.

Structure of DNA• 2 long strands of nucleotides in a spiral shape.

• Ladder-shaped when “untwisted”.

• The sides of the DNA “ladder” consist of alternating

(sugar) and

molecules.

Deoxyribose

Phosphate

• The rungs of the DNA “ladder” consist of

Nitrogen bases

DNA nucleotide• One nucleotide is one piece of DNA.

• Consist of three parts:–Deoxyribose (sugar)–Phosphate–Nitrogen base (A, T, C, G)

There are 4 possiblenitrogen bases in DNA:

(A)(T) (C)(G)

Adenine

Guanine

ThymineCytosine

Deoxyribose

(sugar)

PHOSPHATE

NITROGEN BASES (A, T, C, G)

Deoxyribose

(sugar)

PHOSPHATE

PHOSPHATE

•adenine always pairs with•guanine always pairs with

thymine

cytosineThis is known as

complimentary base pairing.