chapter 10- cell division and cancer

cell cycle

stages a cell goes through to divide

• prep phases: G1, S, G2

• division phases: mitosis and cytokinesis

interphase

where the cell spends most of its time to get ready for the cell division (chromosomes loosely gathered in nucleus)

• G1- cell grows larger and begins to produce more cytoplasm and organelles

• S- synthesis cells DNA is replicated, chromosomes are duplicated

• G2- cell preps to enter division phases

sister chromatids

2 identical DNA molecules

mitosis

sister chromatids of each replicated chromosome becomes evenly divided between 2 daughter cells.

prophase

chromosomes begin to coil up

metaphase

chromosomes align in the middle of the cell

anaphase

fibers called microtubules shorten, separating sister chromatids

telophase

daughter cell and nuclei are formed

cytokinesis

cytoplasm divides, daughter cells are formed

• each have one chromatid

• enters G0 after cells are done dividing, resting period

carcinogens

anything that causes cancer

cell cycle checkpoints

cellular mechanism that ensures a stage of cell cycle is complete

apoptosis

cellular suicide

tumor

mass of cells resulting from unmatched cell division

centromere

where sister chromatids are joined

mitotic spindle

separates sister chromatids

proto-oncogenes

gene that codes for a protein that helps cells divide in response to appropriate signals

• promotes cell division and increases cancer

oncogenes (gas pedal)

mutates and overactive form of pro-oncogenes

• drive cells to divide continuously

• cause cancer

tumor suppressor genes (brake pedal)

gene that codes for a protein that maintains and check cycle progression

• decreases cancer

benign tumor

noncancerous tumors whos cells will not spread throughout body

malignant tumor

cancerous tumors that will spread

metastasize

spread of cancer from one place to another in a body

contact inhibition

characteristic of noncancerous cells that prevents them from dividing once they have filled a space and are in contact w their neighbors

anchorage dependence

need for cells to be in physical contact w another layer of cells or a surface

angiogenesis

growth of new blood cells

chemotherapy

treatment that uses chemicals to kill cancer by interfering with cell division

radiation therapy

beams of high energy radiation focused on a tumor

targeted therapies

specifies for cancer cells and not harmful to noncancerous cells (PARP)

immunotherapies

immune system fights off cancer on its own

mammogram

x-ray of breasts