Bootcamp Chapter 5 Flashcards
Karyotyping is performed at which stage of mitosis?
Metaphase
Cytokinesis begins at the end of which stage of mitosis?
anaphase
Animal cells will undergo cytokinesis via the formation of a ___ ____, while plant cells separate via a ___ ____.
cleavage furrow, cell plate
Which stage is characterized by the shortening of acting and myosin microfilaments as the plasma membrane is pulled to the center?
cytokinesis
T/F - In plant cell cytokinesis, the plant cells do not actually separate and are instead cemented together by middle lamellae.
TRUE
This checkpoint ensures everything is ready for DNA synthesis before proceeding to the next phase in interphase.
G1
Which phase of interphase will provide sister chromatids?
S phase - sister chromatids/DNA synthesis
Organelles are replicated and the cell undergoes rapid cell growth as it prepares for cellular division in the ____ phase.
G2
Identify and describe the functional limitations of the cell cycle?
Surface to volume ration - cellular exchange becomes harder as this decreases and eventually leads to cell death or division; cell exchange is easier when the cell is large
Genome to volume. - this does not change throughout a cell’s life; as G/V decreases, the cell exceeds its ability of its genome to produce enough proteins for regulation in the cell
What are the 5 cell specific regulations to cell division?
1) cell cycle checkpoints
2) cyclin-dependent kinsases
3) growth factor
4) density dependent inhibition
5) anchorage dependence
Which checkpoint will ensures for proper cell growth and favorable conditions?
End of G1 - restriction point
Which checkpoint evaluates the accuracy of DNA replication and will signal whether to begin mitosis?
What hormone will allow it mitosis to proceed?
End of G2
MPF
Mitosis will stop if the chromosomes are not ______ to the ____ _____; this is evaluated during the _____ checkpoint, which occurs during ______.
attached, spindle fibers, M, metaphase
CDK enzymes function to regulate the cell cycle by _______ and are activated by the protein ______.
phosphorylation, cyclin
T/F? Most cells only divide when attached to an external surface.
TRUE
Describe how cancer drugs work to inhibit mitosis of cancer cells.
Disrupt microtubules by preventing them from separating chromosomes during anaphase > stop replication
Myeloma
cancerous plasma cell
T/F? There is no separation of sister chromatids in meiosis I
TRUE
Identify and describe the sub-steps of Prophase I.
Leptotene - chromosomes condense
Zygotene - synapsis begins, formation of synaptonemal complex
Pachytene - synapsis is complete, crossing over begins
Diplotene - synaptonemal complex disappears
Diakinesis - nuclear envelope fragments, chromosomes complete condensing, tetrads are ready for metaphase
Crossing over will occur during ______ ____ of meiosis, specifically during _____.
prophase I, pachytene
T/F - In prophase II, the nuclear envelope will disappear, but the chiasmata are still present.
FALSE
What events will produce genetic variation from recombination events?
crossing over, independent assortment, and random joining of gametes
When are chromosomes best seen under a microscope?
Metaphase
Once sister chromatids separate during _____, they are now considered a ______.
What does this mean?
anaphase, chromosome
This means that the chromosome and chromatid number are now EQUAL
The (chromasome/chromatid) number will only change if the sister chromatids separate in mitosis.
chromosome; only changes in anaphase and telophase
T/F? A change in chromosome and chromatid numbers is not seen in meiosis I.
TRUE
In anaphase II, the sister chromatids will split apart, which will ___ the chromosome number
double
