The Blue Print of Life

DNA the Molecule DNA is a very long polymer. The basic shape is like a twisted ladder or spiral staircase. This is called a double helix.

DNA the Molecule 2’ 3’ 4’ 5’ 1’

Genome A genome is an organism's complete set of DNA, including all of its genes. Each genome contains all of the information needed to build and maintain that organism.

Cell Replication - Duplicating DNA Two cell types Prokaryote Eukaryote Prokaryotes are simple and much less complicated than Eukaryotes therefore they contain much less genetic information (DNA).

Prokaryote cell division Binary Fission Prokaryotic cells have a circular DNA molecule attached to the inner cell membrane They divide through a simple form of division called Binary Fission E. coli dividing by binary fission

Prokaryotic cell division 3 step process DNA strand splits and forms a duplicate of itself. The two copies move to opposite sides of the cell Cell membrane forms between two new and identical cells.

Eukaryotic Cells 50 µm Figure 12.3 1,000 times more DNA then an average prokaryotic cell. All eukaryotic cells store genetic information in chromosomes. Most eukaryotes have between 10 and 50 chromosomes in their body cells. Human cells have 46 chromosomes. 23 pairs

Chromosomes

Chromosomes Organization is much more complex than the single, circular DNA molecule in a prokaryotic cell Linear organized into coils wrapped around proteins called histones. Condenses during cell division

Chromosome Jumping Jacks = Sister Chromatids Center of the jumping jack is the CENTROmere

Chromatin Complexes of DNA and protein are called chromatin. In humans, a copy of the entire genome—more than 3 billion DNA base pairs—is contained in all cells that have a nucleus.

Gene A gene is an address – a location on the chromosome and in the DNA sequence where info for a specific trait is located.