DAT Cell Division Flashcards
cytokinesis
cytoplasmic division
(karyokinesis)
nuclear division
homologous
chromosomes
are two copies of every
chromosome, forming pairs called
Humans have how many chormosomes
46
how many homologous pairs
23
Animal cells have cellular structures called
centrosomes
what does each centrosome contain a pair of
centrioles
what do centrioles produce
spindle fibers
what are the two main phases of the cell cycle
interphase and mitotic phase
interphase includes what
G1, S, G2
mitotic phase includes what
mitosis and cytokinesis
Interphase begins after…
after mitosis and cytokinesis are complete
(when the cells are replicated and physically separated).
Most
cell growth in volume occurs in what
G1
Cell increases in size and G1 checkpoint ensures
everything is ready for DNA synthesis (cells produce protein,
ribosomes, and mitochondria, replicates organelles).
G1
DNA synthesis occurs in what part
S phase
when are sister chromatids made
s phase
when is DNA replicated
s phase
second molecule of DNA replicated from
the first, creating sister chromatids.
s phase
Rapid cell growth continues to occur.
G2
Preparation of
genetic material for cellular division.
G2
Some organelles replicate.
G2
Inactive state of cells not actively growing or dividing
G0
what kind of cells are found in G0
nerve and cardiac cells
When Surface area to
Volume ratio (S/V) is small…
cellular exchange
is hard, and leads to cell
death or cell division to
increase surface area.
why cells are limited in how
large they can grow.
surface to volume ratio
As Genome to Volume ratio
(G/V) decreases,…
cell
exceeds the ability of its
genome to produce proteins
needed to regulate the cell.
when does The spindle apparatus forms
prophase
kinetochore
microtubules attach to
Prophase has how many chromosomes and chromatids
46 chrome, 92 chromatids
Nucleus disassembles, (mitosis)
prophase
nucleolus disappears. (mitosis)
prophase
Chromatin condenses into chromosomes. (mitosis)
prophase
Chromosomes line up. mitosis
metaphase
how many sister chromatids do each metaphase chromosome consist of
2
Each chromatid is complete with what I metaphase
centromere and attached kinetochore.
Microtubules shorten and each chromosome is pulled apart into two separate
chromatids
anaphase
(disjunction).
Chromosomes pulled to
opposite poles
Nuclear envelope re-forms.
Telophase and cytokinesis
Chromosomes decondense back
into chromatin and nucleoli reappear.
telophase and cytokinesis
synapsis,
Chromosomes pair up lengthwise
what does synapsis form
tetrads
what need to form for crossing over to occur
tetrads
occur. Pairs are
physically linked through…
chiasmata
where does crossing over occur
chiasmata
Microtubules attach to chromosomes at kinetochores and move
them towards the metaphase plate (meiosis i)
prophase i
Homologous chromosomes are arranged at the metaphase plate
metaphase i
Independent assortment of chromosomes
metaphase i
Homologous chromosomes separate and spindle apparatus guides the
chromosomes to opposite poles
anaphase i
Homologous chromosomes are separated from each other to each end of the
cell.
Telophase I and cytokinesis
Cytokinesis then results in two
haploid daughter cells
Spindle apparatus forms and microtubules move chromosomes towards
metaphase plate
prophase ii
Sister chromatids are no longer genetically identical due to crossing over
metaphase ii
Chromatids separate, moving towards opposite ends
anaphase ii
Results in four genetically distinct daughter cells in total
Telophase II and cytokinesis
crossing over occurs
prophase i
(non-sister chromatids of two homologous chromosomes exchanging genetic
material)
crossing over
random orientation of homologous chromosomes allows for the
production of gametes with many different assortments of alleles
independant assortment
sperm fertilizes which egg)
Random joining of gametes
genetic linkage.
Genes closer together on a chromosome are more likely to be inherited together,
