Cell Division Flashcards
(50 cards)
functions fo cell division
(1) growth and development (early embryonic development)
(2) repair of damaged tissues and organs
(3) formation of sex cells
sequence of phases in the life cycle of the cell
cell cycle; 90% preparation and 10% execution
what are the two phases of cell cycle?
(1) interphase (G1, S, G2)
(2) M phase
what is G0 phase?
resting phase
true or false: prokaryotes and eukaryotes undergo mitosis and meiosis.
false. prokaryotic cells are simpler structures and have different genetic materials and cellular organization from eukaryotes
decribe eukaryotic cells
has membrane-bound nucleus and organelles; structurally large and complex; larger genome; typically diploid
describe prokaryotic cells
no membrane-bound organelles; structurally small and simple; smaller genome; typically haploid
what are chromatids?
identical copies of a chromosome
what are chromatins?
DNA = histone proteins that condense to form chromatids
what are chromosomes?
highly condensed chromatin fibers carrying genes and are involved in cell division
chromosomes are composed of ___.
(1) chromosome arms (p and q arm)
(2) centromere
(3) kinetochore
(4) telomere
region of DNA where sister chromatids are joined
centromere
protein complex assembled on centromere and where spindle fibers attach
kinetochore
protects chromosome ends
telomere
number of complete sets of chromosomes in a cell is also known as ___.
ploidy level
differentiate haploid from diploid
haploid (n) : one set and a result of gamete formation
vs.
diploid (2n) : two sets and a result of fertilization
what cells are involved in mitosis? what is its result?
germ and somatic cells; two identical daughter cells (chromosome number is maintained)
mitosis in multicellular organsism vs unicellular organisms
for growth and development and replacement fo worn tissue
vs.
mode of reproduction
growth phase; cells increase in size
G1 phase
DNA replication phase
s phase
growth phase and preparation for mitosis; DNA repair
G2 phase
what happens during prophase?
(1) chromatin fibers condense into chromatids
(2) nucleolus and nuclear membrane dissolve
(3) formation of spindle fibers
(4) centrosomes start to migrate to the poles
what happens during metaphase?
(1) chromosomes align at the middle (metaphase plate) : most condensed state
(2) spindle fibers attach to the kinetochore
what happens during anaphase?
(1) sister chromatids separate and migrate toward the opposite poles