Mitosis and Meiosis Flashcards
In what types of cells can mitosis occur?
In all. Mitosis will only give identical cells, so it does not matter if they are haploid, diploid or etc.
Why do cells undergo mitosis?
The cell needs to create daughter cells to cope with lost ones (repair), create new ones for growth, to produce new organisms (asexual way of reproduction),. Mitosis is also implicated in the process of immunity. The process of aging also arises from mitosis
Give an example of an uncontrolled mitosis.
Cancer. The checkpoints do not work well and growth is thus uncontrollable.
Would you expect an adult or a child to do more mitosis? Why?
Children. They grow a lot while adult do not grow anymore. Furthermore, some old people seem like they are shrinking.
What are the stages of mitosis in order?
Prophase, prometaphase, metaphase, anaphase, telophase
What steps are in the cell cycle but not in the mitosis process?
Interphase (G1, S-Phase, G2). Cytokinesis can not be quite included here because it starts in late anaphase or early telophase.
In what phase of the cell cycle does the cell pass the most of its life?
In the G1 process because a lot of metabolic activity occurs in here before going on with the big move of mitosis.
What would happen if SPF was produced without it being ready?
SPF comes after G1 when the size, the growth rates and the nutrients in the cell are adequate. The S-phase is thus initiated. In this case, the cell would not have enough nutrients to replicate DNA and some genes might be missing due to an uncompleted gene expression during protein synthesis. DNA would replicate without the cell being ready for it.
What happens to the chromosomes during the S-phase?
They go from ss to ds as DNA replicates.
What does S stand for in S-phase?
Synthesis
What would happen if APC was not produced?
APC comes after metaphase to launch anaphase. No anaphase means that sister chromatids could not be separated at the centromere to go in their daughter cell. Thus, The daughter cell would have double-stranded chromosomes and twice the ploidy level of the mother cell because it could not divide into two daughter cells. Without creating a segregation in the chromosomes due to spindle fibers contracting, two regions of the cells are not created and thus the daughter cells are not.
What happens in G2?
The cell prepares for mitosis as it is the period just between S-Phase and the prophase of mitosis. The cell stores enough energy, synthesizes the last proteins that are needed for the big move and duplicate organelles.
What happens when G2 is ok?
When all the energy required for mitosis and all the organelles have been duplicated, the MPF is produced. It is the mitosis-promoting factor.
How do G1 and G2 differ?
G1 is for metabolic activities in the cell cycle whereas G2 really is before mitosis and stands as a preparation for this process. G1 is longer than G2. G2 has ds chromosomes while G1 has ss chromosomes.
What do G1 and G2 have in common?
They are not part of mitosis and they undertake growth in the cell.
How do we call the period of the cell cycle where G1, G2, G0 and S-phase occur?
The interphase
Of what proteins are kinetochores made?
Cohesin proteins
Why is the nucleolus the last part of the cell that is turned off before mitosis and the breakage of the nucleus?
It is in this organelle that rRNA is synthesized, so it needs to be the last gene to be turned off because it would interfere with all the process of mitosis. Ribosomes would not be able to function and DNA could not replicate.
