Cell Cycle Overview Chapter 12 Cell Cycle The

Cell Cycle Overview Chapter 12

Cell Cycle � The life of a cell from when it is first formed to when it divides › Cells form new cells through cell division �Part of the cell theory!

Cell Cycle

Interphase � Divided into 3 sections or phases › G 1 phase – first gap �Cell grows › S phase – synthesis �Cell grows & copies its chromosomes �Takes the longest amount of time › G 2 phase – second gap �Cell grows & prepares for cell division

Mitotic (M) Phase � Divided into 2 sections or phases › Mitosis �Chromosomes are divided into two new cells �Broken down into 4 -5 phases › Cytokinesis �Cytoplasm is divided to form two new daughter cells � Takes the least amount of time

Cell Cycle

Not All Cells Divide… � If a cell is not going to divide it spends most of its life in G 0 › G 0 – the cell does not grow or prepare to divide, it just functions normally › Cell enters G 0 after completing G 1

Cell Division - Growth � Organisms division grow, add new cells, through cell

Cell Division - Repair � Cell division replaces dead or damaged cells in multicellular organisms › Ex. Bone marrow cells divide to make new blood cells

Cell Division - Reproduction � Unicellular organisms reproduce by cell division › Makes a new organism by dividing �Mitosis (eukaryotes) �Binary fission (prokaryotes) � Multicellular organisms make gametes (sperm & eggs) through a special type of cell division (meiosis)