Recent bio notes // new unit
Prokaryotes do it, not mitosis
Different than mitosis because:
No interphase s
Less dna than eukaryotes, in form of circular chromosome (plasmid)
No spindle fibers
Duplicated c’somes attached to cell membrane.
Cells get bigger, c somes move away from each other, eventually cell wall forms between the 2 as they separate.
There are internal and external signals. EXTERNAL: attached to substrate (anchorage dependence). (Density dependent inhibition). (Growth factors). Know PDGF .
INTERNAL: found in cytoplasm, control whether or not cell with divide. Checking at several instances to make things done.
Cancer cells exhibit neither density dependent inhibition nor anchorage dependence. Pollutant (chemical, radiation,) physical, fat, genetics
If abnormal cells remain at the original site, the lump is called a benign tumor
G0 cells not actively dividing
Meiosis gotta do we the sex
Diploid (2n) while set of DNA and exact copy
Haploid (n) 1/2 of DNA and mixed up. After 1st division start calling cells this
Totally mixed up cells, variety sex
Also know gametes (ovaries and testicles) and somatic cells