Lecture 4 - ANAT - Cell cycle Flashcards
goal of cell cycle
produce 2 genetically identical cells from one precursor cell
2 major phases of cell cycle
- interohase (G1/S/G2)
- mistosis (M)
G1 phase
During the G1 phase, cells accomplish most of their growth. They get bigger in size and make proteins and organelles needed for normal functions of DNA synthesis
what are 2 molecules that drive G1 phase
cyclins and cylin-dependent kinases (CDKs)
synthesis (S) phase
During the S phase of interphase, a cell replicates its DNA, resulting in two identical sister chromatids
G2 pahse
prepare for mitosis
what are 4 stages of mitosis
- prophase
- metaphase
- anaphase
- telophase
prophase
- condensation of chromotins into chromosomes
- nuclear envelope disappears
- nucleoli disappears
- spindles form in cytoplasm
metaphase
- classical alignment of chromosomes
anaphase
- elongation of cell
- sister chromosomes drawn to opposite sides of cell
telophase
- nucleoli reappears
- reassembly of nuclear envelope
- cytokinesis
2 proteins which stop cell cycle
Rb and p53 (when activated)
cyclin checkpoint order
(D), E, A, B
what type of cells in the body can undergo meiosis
germ cells
what are the 2 types of cells in eukaryotes
- germ cells
- somatic cells
what is another name for programmed cell death
apoptosis
how is apoptotis triggered
- exracellular signals eg toxins/radiation
- intracellular signals eg DNA damage/changes in calcium lvls
necrosis
unregulated eg infection/cancer
induced by tissue injury
what are 2 ways cells die
apoptosis
necrosis
