Science

Why do cells reproduce:  Growth - increase in number of cells

                                         Maintenance of existing cells

                                         Repair of damaged cells

What is cellular reproduction:

Enables parent cell to pass on genes & cell components to daughter cells

Process = cell division

Different organisms reproduce by

Cell division in prokaryotes

1. Genetic information = single, circular dna
2. Prokaryotic cell division = Binary fission
3. DNA copying is first
4. Protein ring forms
5. Sep = cross wall forums
6. One genome goes to each daughter cell.
7. End result: 2 genetically identical daughter cells.

DNA: Organized in chromosomes

Accurate passage of genetic info is difficult.

Chromosomes help organize the process

remember:

Genes = code for protein

Genes = Sequences of nucleotides

           = Segments of dna double helix

Chromosome Contains:

Dna double helix

Centromere

Histones:  Proteins packaged with DNA (Chromatin)

DNA Orginsations:

Chromosomes occur in homologous pairs

Each homologue is same length and contains same genes in same order.

Diploid: cells with pairs of chromosomes (2n)

Found in most cells of the body