Chromosomes
What is the role of the Kinetochore in sister chromatids?
It provides a location for the spindle fibers to attach
NOT DNA
ex: Mitochondria, Golgi, Ribosomes
What occurs in Prophase?
Nuclear envelope degrades
Spindle fibers form
Chromosomes condense
Centrioles move to opposite poles
What are the 3 checkpoints throughout cell division?
(Interphase and Mitosis)
G1, G2, and M checkpoints
What are the 3 cell cycle proteins?
Cyclin Dependent Kinases
Cyclins
p53
What protein connects sister chromatids together?
What is made during the S phase?
DNA is duplicated
(S for synthesis)
Steps of Prometaphase
Microtubules attach to chromosomes
Chromosomes are moved towards center
What does the G1 checkpoint look for within the cell?
Do we need more of the cell (Should the cell divide?)
Cell size (Is the cell large enough?)
Will the daughters be viable (Is there enough nutrients?)
How are secondary tumors formed?
They metastasize and from secondary tumors separate from the original tumor
What is the conformation (shape) of DNA in a non-dividing cell and a dividing cell?
Non Dividing: Chromatin
Dividing: Chromosomes
What occurs during the G2 phase?
Prep for Mitosis
Check for DNA errors, repairs if needed
ex: are there erros within the DNA, did everything duplicate correctly?
Metaphse steps
Chromosomes are lined up on the metaphse plate
Chromosomes are ready to be separated
What does the G2 checkpoint make sure of?
DNA Replication was successful
Check for DNA damages
Allows cell into Mitosis
What is the difference between benign and malignant tumor.
Malignant tumors can spread through the body
Determine the ploidy of Gametes and Somatic cells?
Somatic cells are diploid
Gamete cells are haploid
What two checkpoints occur during Interphase?
G1 and G2 checkpoints
Anaphase steps
Cohesin proteins are cleaved
Sister chromatids are separated and moved to opposite poles
Cleavage furrow forms (cell plate or septum)
What does the M checkpoint check for?
Checks for spindle fiber formation, and proper attachment to chromosomes
What is the role of MPF's (Maturation-Promoting Factor)
A cyclin-CDK complex that triggers passage from G2 to Mitosis
How many kinetochores are in 6 chromosomes?
12 (one on each chromatid)
What process does a cell undergo if the DNA is unrepairable during G2?
Apoptosis
Telophase steps
Nuclear envelope reforms
spindles degrade
Chromosomes uncondensed into chromatin
Cytokinesis separates the 2 daughter cells
What results from checkpoints failing?
Cancerous cells leading to tumors
What can be mutated or suppressed to facilitate growth of cancer cells?
p53 and proto-oncogenes
p53-Repairs DNA, guides apoptosis
Proto-oncogenes- Regulatory proteins that facilitate cell growth