1. DNA

2. DNA fingerprinting is the analysis of DNA from samples of body tissues or fluids in order to identify individuals
DNA fingerprinting is done by electrophoresis

3. In each cell (about 60 trillion cells in the human body) are the genetic materials, chromosomes. On the chromosomes are nearly 30,000 genes.
The gene is the fundamental unit of heredity. It instructs the body cells to make proteins that determine everything from hair color to our susceptibility to diseases.

4. In other words…
CELL
NUCLEUS
CHROMOSOMES
GENES
DNA!

8. Each gene is composed of DNA
that is designed to carry out a
specific function

9. DNA is a polymer (A substance composed of a large number of atoms- the atoms are usually arranged in repeating units).
The units of DNA are known as nucleotides. A nucleotide is composed of a sugar molecule, a phosphorous-containing group, and a nitrogen-containing molecule (called a base).
The bases are adenine, guanine, cytosine, and thymine.

10. There are 3 billion nucleotides in human DNA
99% is identical among individuals
The remaining 1% contains a significant amount of code variations between individuals
Due to the large number of variations no two people have the same DNA sequence (except for Identical twins)

11. The DNA molecule (modeled by Watson and Crick) is two DNA strands coiled into a double helix. In the double helix, adenine (A) binds with thymine (T) and cytosine (C) binds with guanine (G)---after Chargaff’s rule.
These pairs are known as complementary base pairing.

12. There are countless ways
to combine the complementary
base pairs on a DNA strand.
The average human chromosome
has DNA containing 100 million
base pairs

13. How DNA works
The inheritable traits that are controlled by DNA come from the ability to direct the production of proteins. Proteins are made by linking amino acids together.
There are thousands of known proteins, but they are all derived from 20 known amino acids.

15. The sequence of amino acids, codes for the shape and function of the protein.
Your DNA is responsible for determining the amino acid sequence. The sequence of bases on a DNA strand is responsible for coding for a particular amino acid.
Each amino acid is coded by a sequence of three bases.

17. EX. C-G-T codes for the amino acid alanine.
EX. Take into account the DNA strand:
-C-G-T-C-T-A-A-A-A-C-G-T-
The triplet code contained in this segment of DNA translates into:
[C-G-T]-—[C-T-A]-—[A-A-A]—-[C-G-T]
Alanine - aspartate - phenylalanine – alanine