Cell Cycle and Cancer Flashcards
Proto-oncogenes
dominant gene responsible for encouraging cell growth; one mutated allele results in cancer
tumor suppressor genes
recessive gene responsible for slowing cell growth; two mutated alleles results in cancer
what two combinations of mutations are needed for cancer to occur
mutations in both proto-oncogenes and tumor suppressor genes, or just a mutation in tumor suppressor genes
cancer can be caused by
- chemicals (asbestos, tobacco products)
- radiation (X-Rays, UV light)
- viruses (HPV)
Chromosome
Coiled DNA
Histones
first level of organization in a chromosome; what DNA is wrapped around
nucleosomes
group of DNA wrapped histone proteins that organize the DNA and seperate genes
chromatin
disorganized and spaghetti-like DNA
interphase
phase in which the cell grows and synthesizes DNA to produce proteins, phase in which centrioles divide. it is the longest phase in mitosis.
Prophase
DNA coils into chromosomes and the nuclear membrane fades, centrioles grow spindle fibers
Metaphase
chromosomes align at the center and spindle fibers attach
Anaphase
spindle fibers align at cell poles and the cell membrane breaks down
Telophase
chromosomes are pulled apart and the membrane reforms leaving two daughter cells
Binary Fission vs Mitosis
binary fission is the only way the organism can reproduce, creates an exact copy; mitosis is used for growth and it creates a genetic copy but not a perfect copy
Mitotic index
number description for how much mitosis is happening by percent
( # cells in mitosis / # cells total ) * 100
