KEY CONCEPT Cell cycle regulation is necessary for healthy growth.

Internal and external factors regulate cell division. External factors include physical and chemical signals. Internal factors include what is coded for in genes.

Carcinogens are substances known to promote cancer Smoke, radiation, UV rays Standard cancer treatments typically kill both cancerous and healthy cells.

Cancer cells do not carry out necessary functions. Cancer cells come from normal cells with damage to genes involved in cell-cycle

Tumors are disorganized clumps of cells. Benign tumors remain clustered and can be removed….NON-cancerous. Malignant tumors metastasize, or break away, and can form more tumors…are cancerous cancer cell bloodstream normal cell

Apoptosis is programmed cell death. a normal feature of healthy organisms Your cells with “kill” themselves in cell cycle if they find out there is an error occurs in development of infants to make your fingers! webbed fingers