Cell Cycle & Mitosis Flashcards
What are the two reasons why cells have to divide?
Surface area and volume ratio
DNA overload
Explain what DNA overload means
The larger a cell becomes, the more demands the cell places on DNA. Eventually, the cell needs to copy its DNA and divide it between new cells.
In a living cell, what part of the cell represents surface area and which part of the cell represents volume?
The cell membrane represents the surface area, and the cytoplasm represents volume.
What are some adaptations that cells have developed that allow for a greater surface area volume ratio?
The cell divides.
Cell division occurs in two main stages. What are they?
Mitosis and meiosis
What is the cell cycle?
A series of events that cells go through as they grow and divide.
What are the 4 stages of the cell cycle?
G1, S, G2, M
Explain each stage of the cell cycle.
G1: Where the cell grows
S: replicates DNA
G2: Prepares for cell division
M: nucleus & cytoplasm divides
What is the G0 stage? Give 3 examples of cells that, once matured in the G1 phase, enter the G0 stage indefinitely.
Where cells go that don’t divide, neurons, cardiac cells, sex cells
Cells spend most of their lifetime in what stage? What 3 phases of the cell cycle does this include?
Interphase, G1, S, G2.
What are the four stages of mitosis, in order?
Prophase, Metaphase, Anaphase, & Telephase.
Prophase
Centrioles move to opposite sides of the cell.
Spindle fibers start to form.
Chromosomes form.
Nuclear envelope dissapears.
Metaphase
Centrioles are on opposite sides.
Spindles fully form.
Chromosomes line up in the middle of the cell.
Anaphase
Spindle fibers pull chromosomes apart.
Telophase
Nuclear envelope splits and reforms in 2 new cells.
Cytoplasm starts to split.
