*Unit 3 Part 7: Cell Division Flashcards
Cells, Cell Transport, & Mitosis
All living cells come from __________ cells.
Preexisting
New cells are made by ___________________.
Cell Division
What is the definition of the cell cycle?
The repeating process of growth, development, and reproduction that a typical cell goes through.
What happens in Interphase?
- Cell growth and development
- DNA is copied
What happens in Mitosis?
- Nuleus divides
What are the 4 stages of Mitosis in order?
- Prophase
- Metaphase
- Anaphase
- Telophase
pmat
What happens during Cytokinesis?
The cytoplam divides
What happens during G 0 phase?
The cell no longer goes through cell division
Where do cells spend most of their time?
Interphase
What are the stages of Interphase in order?
G1 phase, S phase, G2 phase
What happens during G1 phase?
Normal routine cell growth
What happens during S phase?
DNA is copied
(S stands for SYNTHESIS)
What happens during G2 phase?
Preparation to divide
What is a checkpoint?
The points where the cell cycle is paused
When do we want cells to divide?
When there is a need for growth and repair
What is cancer?
The uncontrolled growth of cells
Why does cancer occur?
Cancer occurs because of mutations in genes that cause cells to continually divide.
What is a mutagen?
something that causes mutations
What is a carcinogen?
something that causes mutations that lead to cancer
What are examples of carcinogens?
Ionising Radiation, Smoking, UV Pollution. Air Pollution, Alcoholic Drinks
What is DNA?
molecules that carry genetic information
What is a gene?
a segment of DNA that codes for one trait
About how many genes do humans have?
25,000 genes
What are chromosomes?
genes that are packaged in bundles
How many chromosomes do humans have?
46 chromosomes
When are chromosomes copied?
Before or After the cell divides?
before the cell divides
Why are chromosomes copied before the cell divides?
so that the amount of genetic material stays the same
What do centrioles do?
anchor spindle fibers
What do spindle fibers do?
pull chromosomes to ends of cells
What is a sister chromatid?
identical copies of chromosomes held together at the centromere
