General Info
What is the cell cycle?
Ordely set of stages from the first division of a eukaryotic cell to the time the resulting daughter cells divide.
What are the stages of interphase?
G1 (G0), S, G2
What happens to the nucleus and its related organelles during prophase?
Nuclear envelope fragments and nucleolus disappears
What happens in metaphase?
Chromosomes lined up in middle of cell.
What happens in telophase?
Spindle disappears and nuclear envelope forms
What are the three major stages of the cell cycle?
Interphase. mitotic stage, cytokinesis
Which stage of interphase is DNA replicated in?
S stage
What happens to chromatin during prophase?
They condense and are visible with a microscope.
When do chromosomes become daughter chromosomes?
When they are pulled apart.
What is cytokinesis?
Division of cytoplasm
Which stage does the cell cycle spend the most time in?
Interphase
What is the G0 stage and what are some examples of cell that remain here?
G0 is the resting phase of cell cycle-cell is functioning without preparing to divide.
Nerve cells, muscle cells
What are kinetochores and why are they important?
Protein that connects chromatid to microtubules, important for attaching spindle so they can pull chromatids.
What is the metaphase plate?
Represents plane through which mother cell will be divided.
When does cytokinesis often begin?
Anaphase
What happens just prior the cell division?
Cell grows larger, number of organelles doubles, DNA is replicated.
G1 checkpoint: Cell checks if DNA is damaged, otherwise cell is committed to divide if growth signals and nutrients are available.
What is the centrosomes and what is it's function?
Microtuble-organizing center in animal cells. Has two barrel-shaped centrioles.
When does the centromere dissolve, releasing sister chromatids?
Is the cell divided just after telophase, why?
No, cytoplasm needs to be divided.
What is apoptosis?
Programmed cell death
Describe the chromosome and chromatid count before and after DNA replication.
Before: 1 chromatid each (46 chromosomes, 46 chromatids)
After: 2 identical chromatids (46 chromosomes, 96 chromatids)
What are asters?
Microtubules that form star-like arrays in animal cells
What checkpoint is present in Metaphase?
M checkpoint: delays anaphase until kinetochores are attached properly.
How does cytokinesis differ from plant and animal cells?
Animal cells: cleavage furrow forms in telophase, eventually pinching mother cell into two
Plant cell: cell plate forms and plasma membrane forms, cell wall forms later.