Chapter 10 - Cell Growth and Division Flashcards
Why do cells divide?
- Size
- Reproduction
- Repair
- Growth
How do you find the surface area to volume ratio of a cell?
Find the surface area and volume of a cell, then set the surface area over the volume. Then simplify it.
What is the surface area to volume ratio if a cell has a surface area of 6cm^2, and a volume of 1cm^3?
6:1
What is the surface area to volume ratio if a cell has a surface area of 24cm^2, and a volume of 8cm^3?
3:1
What is the surface area to volume ratio if a cell has a surface area of 57cm^2, and a volume of 27cm^3?
2:1
Do larger or smaller cells function more efficiently?
Smaller Cells
What is sexual reproduction?
Two of the same species - one male and one female - combine 23 chromosomes of their own together to make unique offspring.
What is asexual reproduction?
One individual of a species copies its own DNA / genes exactly, then makes identical offspring to itself.
What are chromosomes?
They carry genetic information/DNA. They are each made of two chromatids held together by a centromere.
What is another name for a chromosome?
Sister chromatids
What is a chromatid? Does it have wound or unwound DNA?
This is one half of a chromosome. This has wound DNA.
What are sister chromatids, and what is one other name for it?
Sister chromatids are two chromatids held together by a centromere. One name for it is “chromosome.”
What is chromatin, and when do you see it in cell reproduction?
Unwound DNA; found during interphase of mitosis and in interphase 1 of meiosis.
What is centromere?
It holds the chromatids together to form sister chromatids.
What are the stages of mitosis? Remember the acronym.
- Interphase
- Prophase
- Metaphase
- Anaphase
- Telophase
- Cytokinesis
In interphase, what is the G₁ Phase?
This is the growth phase, when the cell reaches the point that it is too big, so it can no longer sustain itself.
In interphase, what is the S Phase?
This when DNA is replicated.
In interphase, what is the G₂ Phase?
This is when the cell prepares for mitosis, and makes a copy of each organelle.
What happens in prophase, and how much time does it take (in percent)?
The chromatin forms into chromosomes, the nuclear envelope begins to disintegrate, and the spindles begin to form. It can take as much 50-60% of the time in mitosis.
What happens in metaphase?
The chromosomes line up in the middle of the cell, and a spindle fiber connects to each chromatid.
What happens in anaphase?
The spindles pull the sister chromatids apart, separating them into four chromatids on each side.
What happens in telophase
The organelles and chromatids separate to opposite sides of the cell, and the membrane begins to furrow. The nuclear envelope begins to reform.
What happens in cytokinesis?
The cell completely splits, and the chromatids turn back into chromatin.
