Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

A-level Biology > Cell Cyles, Mitosis/ Meiosis And Binary Fission > Flashcards

Cell Cyles, Mitosis/ Meiosis And Binary Fission Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What is the eukaryotic cell cycle?

A

Interphase (G1, S, G2)

Mitosis/meiosis

Cytokinesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What happens during G1 of interphase?

A

Organelle replication
Increase in the cell size
Biosynthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does the checkpoint between G1 and S phase ensure?

A

Ensures the cell is ready to enter S phase
Some cells triggered by the checkpoint may enter G0 ( apoptosis or cell death)

The cell cycle cannot be reversed so DNA replication can only happen once per cell cycle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What happens during S phase?

A

DNA replication
Commits the cell to complete the cell cycle
Rapid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What happens during G2 phase of interphase?

A

The cells grow

Chloroplast and mitochondria DNA replicates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does the checkpoint between G2 and mitosis/ meiosis ensure?

A

Stimulates spindle forming proteins

Triggers condensation of chromatin (components of material in a chromosome)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How is the cell cycle regulated?

A

Via checkpoints

These ensure cell division is controlled and detect any damage to the DNA which may causes genetic disorders

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the stages of mitosis?

A

Prophase
Metaphase
Anaphase
Telophase

Cytokinesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens during prophase of mitosis?

A

DNA supercooling
Nuclear envelope breaks down
Centrioles divide and new centrioles move to the poles
Spindle fibres form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What happens during metaphase of mitosis?

A

Sister chromatid pairs attach to spindle via their centromeres.

The chromatid pairs line up along the equator of the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What happens during anaphase of mitosis?

A

Centromere of each chromatid pair splits

Motor proteins drag the chromatids towards the poles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens during telophase of mitosis?

A

New nuclear envelopes form around the chromosomes

Cell contains two nuclei

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What happens during cytokinesis?

A

The cell splits forming two genetically identical daughter cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why is meiosis important?

A

Important for sexual reproduction and to increase genetic variation
( through random fertilisation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is a diploid cell?

A

Cell that contains two sets of chromosomes

2N

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a haploid cell?

A

Half the number of chromosomes as a diploid cell

N

17
Q

Define homologous chromosome

A

One chromosome from mother and one from the father but they both code for the same gene with the same loci

18
Q

Define sister chromatid?

A

Genetically identical but 2 together form 1 chromosome

19
Q

What are the products from mitosis and meiosis?

A

Mitosis:
Produces 2 genetically identical diploid cells

Meiosis:
Produces 4 haploid cells not genetically identical

20
Q

What are the stages in meiosis?

A

Prophase I
Metaphase I
Anaphase I
Telophase I

Prophase II
Metaphase II
Anaphase II
Telophase II

Cytokinesis

21
Q

What happens during prophase I of meiosis?

A

Super coiling and compacting of chromosomes

Spindle formation

22
Q

What happens during metaphase I of meiosis?

A

Homologous chromosomes line up next to each other at the equator of the cell(independent assortment) where some may be crossed over

23
Q

What happens during anaphase I of meiosis?

A

Allele reshuffling

Chromosomes pulled to the poles of the cell

24
Q

What happens during telophase I of meiosis?

A

Nuclear envelopes reform

25
Q

What happens during prophase II of meiosis?

A

Nuclear envelopes break down
Super coiling and DNA condenses
Spindles reform

26
Q

What happens during metaphase II of meiosis?

A

Single chromosomes line up on each spindle fibre at the equator of the cell.

Random assortment of chromatids

27
Q

What happens during anaphase II of meiosis?

A

Centromeres divide

Individual chromatids are pulled to each pole

28
Q

What happens during telophase II of meiosis?

A

Nuclear envelope reforms around all f haploid clusters

29
Q

What happens during cytokinesis in meiosis?

A

He cell divides into 4 non genetically identical haploid cells.

30
Q

What is binary fission?

A

The process by which prokaryotic cells divide

31
Q

What are the stages in binary fission?

A
  1. Circular DNA molecules replicate and both copies attach to the plasma membrane.
    Plasmids also replicate
  2. Plasma membrane between the pole begins to grow and elongate
  3. Pinching occurs at the equator of the cell
  4. New cell walls form between the 2 DNA molecules and 2 daughter cells are produced

Numbers of plasmids may vary as there is no guarantee of even distribution

32
Q

What are viruses?

A

A cellular non living particles (not cells) which are parasitic and live of host cells.

33
Q

How do viruses replicate?

A
  1. Attach to host cells via attachment proteins
  2. Insert genetic material (DNA, ssRNA, dsRNA) into host cells.
  3. Host cell Machinery reads these instructions and manufacturers viral components
  4. These are assembled into virons (viral particles) which then get egressed/released into the host body

A-level Biology (23 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions