Prokaryotic and eukaryotic cell cycle Flashcards
Steps of binary fission
.DNA replication- DNA, chromosomes and plasmids mutiple
Elongation-doubles in length and the duplicated DNA moves to opposite ends of the cell
Septum forms between the cells, cell undergoes cytokinesis and pulls in the cell membrane and cell wall
CYTOKINESIS-
2 new cell walls and membrane are formed in centre of the cell
cytokinesis
when the cytoplasm divides into two and 2 seperaet cells form
mitosis
Separation of sister chromatids and the formation of two nuclei
Interphase
Synthesis of DNA, organelles and proteins needed for replication
Stages of mitosis
prophase
metaphase
anaphase
telophase
prophase-what happens to nuclear envelop, what happens to chromatin and what do centrioles produce and where do they move to
Nuclear envelope starts to disappear
Chromatin condenses
centrioles produce from spinlde fibres and migrate to oppostire sides of the cell
contains 46 chromosomes and chromatids
Telophase- what do chorosmomes do, what forms, what happens to chromatin, what happens to nuclear envelope and what other process occurs and how many chromaitds are there during this phase
chromosomes cluster on opposite sides of the cell and two sepereate nucleus form
chromatin become visible no longer an x shape)
Nuclear envelope reappereaa
cytokinesis happens
clevage burrow forms
contains 92 chromatids
How many chromosomes are there in a cell after mitosis is completed(after telophase)
46 chromosomes and 92 chromatids
is mitosis sexual or asexual reproduction
both
When a complete chromsome(shaped as an x) spilts into two, what is it now called
chromatid
How many chromotids in a chromsoem
2 chromatids
how many chromatids in 2 chromosome
4 chromatids
centromere
holds the chromatids together
What is the longest stage of the cell cycle
interphase
3 sub phases of interphase
Gap 1(G1)
Sythensis phase(S phase)
Gap 2(G2)
G0 (resting phase) if further cell replication is not required
What is mitosis required for/ the purpose of cell division is
replacement of damaged cells in muticelluar eukaryotic organsims
what is the G1 phase involved in, what is being duplicated, what happens to the volume of cytsol in the G1 phase, why are proteins created in the G1 phase, why are orangalles replicated in the G1 phase,
Involved in the growth of a cell
all cells are duplicated besides chromsomes
volume of cystol increases
Proteins are created for DNA replication
organelles are replicated to prepare for replication
G1 phase
process to make the cell complete again and duplication of celluar contents besides chromsomes
G2 phase
monitors DNA duplications for growth and preparation for mitosis
G0 phase andexamples
phase of cell cycle where cell is not dividing or being prepared to mutiple
eg.brain cells or heart cells
What kind of cells are in the G0 phase, what are cells like and do in the G0 phase and some cells in this phase are what
cells that are not going to be duplicated are in the G0 phase
The cells in the G0 phase are dormant and can re enter the cell cycle eg. liver and regenerating
Some cells in this phase f damaged cannot be replaced or repaired(terminally deferinated)
S Phase
involved in the synthesis and replication of dna to produce two identical sister DNA chromatids
How are sister chromatids held togehter
centromere
somatic cells
cells in the body that are constantly regenerating (excludin sperm and egg)
Somatic cells in humans are what
diploid(two sets of chrosomomes)
sister chrosomes are regarded as
a single chromosome which spereate in mitosis
Is G2 phase the first or final stage of interphase, what do cells do for mitosis in G2, what happens to the volume of cytsoll and what is synthesised
final stage of interphase
cell grows and prepares for mitossi
volume of cytosl increases
proteins required for mitosis are sythensised
What does prophase do to form chrosomes, what happens to the nucleus
Chromatin condenses to form distinct chromosomes and nuclear membrane breaks down
METAPHASE-What happens to sister chromatids and chrosomes in metaphase
Spindle fibres fully form and attach to the centromere of each sister chromatid
sister chromatids align along the equator
ANAPHASE-what happens to sister chromatids in anaphase and what forms annd what spilts
Sister chromatids are pulled by spindle fibres from the centromere to opposite sides of the cell
DNA spilts
What happens to nuclear membrane and spindle fibres and chromatin in telophase
Two nuclear membrane forms
Spindle fibres disintegrate
chromosomes decondense.
Difference of cytokinesis in animals and plants
in the cytokinesis of animals Cleavage furrow develops and pinches the plasma membrane into two cells
in the cytookensis of plantsA cell plate first forms before separating into two cells
Why do the 3 checkpoints/phases occur and what happens if errors are detected
occur for the cell to inspect for any errors before proceeding to the next stage.
If errors are detected, repair or apoptosis may result.
Diploid
2 sets of chromosomes in a orgnaisms cell(46 chroomes total)
haploid
single set of DNA in organisms cell that contains 23 chroosmes
Where is a hapeloid found
in a gamete
terminus
the end of the DNA
homologous chrosomem
a pair of chromosomes, with exact same DNA howeverv one chrosome is maternal and another paternal
function of centromere
holds together the sister chromatids
In what stages is the nucleus visible and invisble
in prophase nucleus is visible but at the end of prohpahse it is invisible
In telophase nucleus becomesvisible
what do centrioles do
produce spindle fibres
what do spindle fibres do
they pull the chromosomes to opposite ends of the cell
how many chromsomes in the nucleus
46 chromsomes
What two process occur during interphase and are required for mitosis ot take place
growth and replication
Why are roots good for studying the cell cycle
at any given time, you can find cells that are undergoing mitosis.
In what stage do chroems disperse and are no longer visible under light micoscroe
metaphase
In what phase does DNA duplicate to prepare for mitosis
S phase
How long does it take for mitosis to complete?
mitosis and cytokinesis last only about an hour,
95% of cell cycle is in interphase
Why will most of the cells you view be in interphase
Cell growth, DNA sythensis and replication of choromes takes place
difference purspoes of mitosis in eukaryotes single celled vs mutlicelluar eukaryotes
in single celled eukayrotes the purpose of mitosis is reproudction whilst in mutlicelluar eukaryotes it is growth and repair of tissues
what kind are pairs are chromomes in, how main pairs in humans and are the chromsomes linear or ciruclar and what are they composed of
homologous pair, 23 pairs in humans and are linear and chromsomes are made of chromatin
kinetochore
A kinetochore is the patch of protein found on the centromere of each chromatid. It is where the chromatids are tightly connected.
when does Endoplamsic reicutlum and ribsomes get produced, and how does mitochondria and chorlpast priduce
during G1 phase and G2 phase of interphase
mitchondria nad chloroplasts produce through binary fission, independelty of mitosis
when do spindle fibres shorten
metaphase
telophase
chromatin decondenses
nucela envelope starts to reappear
clevaeg furrow forms
2 new cells walls and cell membranes found
cell undergoes cytokinesis
