Cell Cycle Flashcards
What are the two major types of cell division
Meiosis and Mitosis
What cell division do somatic cells undergo
Mitosis
What cell division do germ cells undergo
Meiosis
What happens during G1 - 3
The cell grows, prepares DNA for replication by creating protiens and enzymes, DNA is checked for damage
What happens in S-phase
DNA replication - produces two sister chromatids for each chromosome
What happens during G2 Phase - 2
The cell grows, centrosomes are duplicated
What happens in M-phase
Mitosis occurs
Whats a karyotype
mitotic cells highlighted in dye for the study of chromosomes
difference between sister chromatids and homologous chromosomes
sister are identical copies of a chromosome
homologous are a pair of chromosomes from parents
What are CDK’s
Enzyme that regulates the cell cycle
How do CDK’s work
using phosphorylation and a cyclin to become active
Function of cyclins
bind to CDK’s to become active and regulate stages of the cell cycle
How do APC/C function
triggers transition from metaphase to anaphase by marking securin for degradation activating separase
Mitosis sequence
PPMAT
What happens during metaphase
Chromosomes align in the equator
what happens in prophase -3
chromosomes condense, microtubules begin to form, centrosomes move to the poles of the cell
how are sister chromatids separated and when
anaphase, kinetochores attach spindle fibres and pull to poles after centromere separate
role of telophase -2
nuclear envelope begins to form again with sister chromatids reaching poles
Whats cytokinesis
the division of the cytoplasm
role of CDK-cyclin complex
control transitions between phases of the cell
how are cyclin levels controlled
transcription and degradation
What is the spindle assembly checkpoint
ensures all chromosomes are properly attached to spindle fibres before anaphase
how does the G1/S checkpoint control progression?
checks for DNA damage, ensures the environment is favourable for DNA replication
role of CDK inhibitor
pauses cell cycle
example of when is a CDK inhibitor used
When DNA is damaged
whats crossing over
exchange of genetic material to homologous chromosomes
when does crossing over happen
prophase
What is the result of random assortment in meiosis
genetically unique gametes
why is meiosis important
half chromosome numbers for the formation of gametes to make a diploid zygote
whats a diploid
has two sets of chromosomes
whats a haploid
only contains one set of chromosomes
example of haploid
gamete
What does cyclin D bind too
CDK4 or 6
What does CDK4 or 6 bind too
Cyclin D
What does CDK 2 bind too
Cyclin E or A
What does CDK1 bind too
Cyclin B
What does cyclin E activate
CDK2
What does cyclin A activate
CDK2
What does cyclin B activate
CDK1
