Summary AP Biology Chapter 12

Chapter 12: Mitosis
The Key Roles of Cell Division

Cell Division
 The continuity of life based on the reproduction of cells
o Prokaryotic and Unicellular Eukaryotes
 When they divide, they are reproducing
o Multicellular Organisms
 Develop from a single cell (fertilized) to a two-celled embryo
 Function in renewal and repair in fully grown multicellular eukaryotes
 Replace cells that die from normal wear and tear or accidents
Cell Cycle
 The life of a cell from the time its first formed during cell division until its own division
into two daughter cells

Concept 12.1: Cell Division Results in Genetically Identical Daughter Cells
 Both prokaryotes and eukaryotes most cell division involves the distribution of identical
genetic material (DNA) to two daughter cells

Cellular Organization of the Genetic Material
 Genome
o A cells endowment of DNA, it’s genetic information
o Before the cell can divide the genome must be copied or replicated and then the
two copies must be separated to form 2 daughter cells
 Chromosomes
o One DNA molecule and associated protein molecules
o Replication and distribution of a lot of DNA is possible because DNA is packaged
in chromosomes
o Eukaryotic Cell
 Has multiple, linear chromosomes which are located in the nucleus
o Prokaryotic Cell
 Has a single, circular chromosome found in the nucleoid (a region not
enclosed by a membrane)
 Chromatin
o The entire complex of DNA and proteins that is the building material of
chromosomes
 Somatic Cells
o All body cells except for the reproductive cells
o Ex) humans: 46 chromosomes, made up of two sets of 23
 Gametes
o Reproductive cells (sperm and eggs)
o Have one set, half as many chromosomes as somatic cells
o Ex) humans: one set of 23 chromosomes