3a.1 cell division Flashcards
what are all cells made of?
mitosis
what ar\e the only type of cells not made from mitosies
gametes
when a cell divides by mitosis it…
- splits into 2 daughter cells
-where each has a diploid number of chroms
what are daughter cells?
genertically identical from the cells they came from & each other
what is a diploid
full set of chromosomes
(reg cells)
what is a haploid
half set of chromosomes
(gametes)
what always happens before mitosis?
dna replication
when can mitosis happen?
- asexual reproduction
- repair of tissue
- growth
what are the stages of mitosis
( 5)
- interphase
- prophase
- metaphase
- anaphase
- telophase
interphase blurt?
-b4 mitosis
- DNA replication
- cell organelles are synthesised
prophase
-chromosomes shorten and thicken to become visible
- nuclear membrane breaks down
- spindle fibres appear
metaphase?
- chromosomes line up on spindle fibres
- line up along equator of cell
anaphase?
chromosomes are seperated & pulled away to poles by shortening of spindle fibres
telophase?
- nucelar membranes reform
- chromosomes disperse
- cell divides into 2 via cytokinesis
where would meisos occur
in humans
in plants
ovaries and testes
ovule and anther
what does meisos result in??
genetic variation
how many phases and stages in meisos
2 phases of mitosises, 8 stages
interphase 1
- DNA replication
prophase 1
chromosomes become visible and thicken
homologous pairs line up
non-sister chromosomes join up and trade sections
metaphase 1
- chromosomes line up on spindle fibres
- line up along equator of cell
anaphase 1
-homologous chromosomes attacth to splindles
- splindes contract and pull apart pairs
telo phase 1
- nucelar membranes reform
- chromosomes disperse
- cell divides into 2 via cytokinesis
results in 2 nuclei w 46 chromosomes
prophase-telophase 2
process in general repeated,
one chromatic from each duplicated chromosome , separates
results in 4 haploid daughter cells
meisosi phase 1 and phase 2 difference + blurt
1 - homologous chromosomes separate to create daughter nuclei
2-
2 daughter nuclei divide
-chromosomes separate
creating 4
haploid gametes
whose chromosomes aren’t identical
what makes meisos produce daughter cells which are genetically vaired?
prophase1:
non-sister chromosomes join up and trade sections
mitosis vs meisos:
number of divisions?
MIT: 1
MEI: 2
mitosis vs meisos:
where does it occur?
MIT: all over body
MEI: sex organs
mitosis vs meisos:
creates (cells)…??
MIT: all cells apart from gametes
MEI: only gametes
mitosis vs meisos:
number of chromosomes in each cell…???
MIT: 46 (diploid)
MEI: 23 (haploid)
mitosis vs meisos:
produces number of cells…?
MIT: 2
MEI: 4
mitosis vs meisos:
function??
MIT: asexual reproduction, growth, repair of tissue
MEI: sexual reproduction
mitosis vs meisos:
gives daughter nuclei w/ chromosomes that are…??
MIT: genetically identical
MEI: genetically varied
