Cell Biology: Cell Division Flashcards
1
Q
What are chromosomes made up of of?
A
- chromosomes are made up of DNA molecules
- chromosomes contain genes
2
Q
What is a gene?
A
a section of DNA which codes for a protein
3
Q
How many chromosomes are found in the nucleus of human body cells?
A
46
4
Q
How many chromosomes are found in the nucleus of gametes?
A
23
5
Q
What are the 3 main stages of the cell cycle?
A
- DNA replication
- Mitosis
- Cytokinesis (division of cell)
6
Q
What are the functions of mitosis
A
- essential for growth, development and repair
- as it produces identical cells which all have the same genetic information
7
Q
What happens during the first stage of the cell cycle?
A
- DNA replicates to form 2 copies of each chromosome
- the cell grows in mass
- number of internal structures are increased such as mitochondria and ribosomes
8
Q
What happens during the second stage of the cell cycle?
A
- mitosis
- each chromosome pair is pulled to opposite poles of the cell
- the nucleus divides
9
Q
What happens during the third stage of the cell cycle?
A
- the cytoplasm and cell membrane divide
- two identical daughter cells are produced
10
Q
How do bacterial cells divide?
A
BINARY FISSION
11
Q
What do bacteria require to carry out binary fission?
A
- enough nutrients
- a suitable temperature
12
Q
Under ideal conditions, a type of bacteria divides every 20 minutes. Calculate the number of bacteria present after 3 hours.
A
180/20 = 9
9 rounds of division.
29 =
512
