Focus 7 Feb 20, 21 What is the cell cycle and what happens? (full page) 2. What happens during mitosis and cytokinesis?

The cell cycle is everything the cell does before it undergoes asexual reproduction – also known as cell division

The Cell Cycle: 1. Interphase 2. Mitosis 3. Cytokinesis

Interphase: Normal cell activity-make proteins, repair membrane 2. Cell Growth & DNA replication

Average age of cells in an adult – 7-10years Cell life spans: Stomach lining – 2 days Skin – 2 to 4 weeks Red blood cell – 4 months Bone cells – 25 to 30 years Sperm – 2 to 3 days Small intestine – less than a week Colon – 3-4 days Some immune system cells – 10 hours Heart muscle cells & brain cells – your whole life Skeletal muscles cells – 10 years Average age of cells in an adult – 7-10years Figure: 11.2 Title: Mitotic cell division in eukaryotic cells produces cells needed for growth, development, and maintenance and repair Caption: Mitotic cell divisions produce the cells that make up the body of an embryo . Mitotic cell divisions continue to allow the embryo to grow, eventually, into an adult. (d) In the adult, mitotic cell divisions maintain tissues such as skin that are made of cells with short life spans.

Mitosis & Cytokinesis: 2. 1. Cell division 2.Why divide? -For multicellular organisms to grow -To replace old or damaged cells -For unicellular organisms to reproduce

Mitosis Animations http://www.cellsalive.com/mitosis.htm

Stages of Mitosis Complete handout