Brainscape's Knowledge GenomeTM

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


See full index

module two biology > cell division > Flashcards

cell division Flashcards

1
Q

What does the cell cycle consist of?

A

Interphase (G1, S, and G2) mitosis and cytokinesis

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

What does the cell cycle lead to?

A

Genetically identical cells

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

How is the cell cycle regulated?

A

Checkpoints which control the cycle.

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

Where are the checkpoints in the cell cycle located?

A

After G1, after G2 and during metaphase

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

What does the G1 checkpoint check for?

A

The chemicals needed for replication are present, any damage to DNA and growth

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

What does the G2 checkpoint check for?

A

If all of the DNA has been replicated properly, if there is any damage, and if it is big enough.

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

What does the metaphase checkpoint check for?

A

The cell checks chromosomes are attached to the spindle before mitosis can continue

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

What are the main stages of mitosis?

A

Prophase, metaphase, anaphase, telophase

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

Why is mitosis important for life cycles?

A

It’s important for growth, tissue repair and asexual reproduction in plants animals and fungi

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

Why is meiosis significant in life cycles?

A

It produces haploid cells and genetic variation by independent assortment and crossing over

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

What happens in G1?

A

The cell grows and new organelles and proteins are made.

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

What happens during S phase?

A

S phase strands for synthesis, the cell replicates its DNA and gets ready to divide by mitosis

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

What happens in G2?

A

The cell continues to grow and proteins needed for cell division are made

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

What happens in M phase?

A

Mitosis and cytokinesis

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

What happens in interphase?

A

The cell prepares to divide, is DNA is unraveled and replicated to double its genetic content. The organelles are also replicated and ATP content is increased

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

What happens during prophase?

A

The chromosomes condense, and tiny bundles of protein called centrioles move to opposite ends of the cell. This forms a network of protein fibres called the spindle. The nuclear membrane breaks down and chromosomes lie free in the cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens in metaphase?

A

The chromosomes each with two chromatids line up along the middle of the cell. They become attached to the spindle by their centromere. The metaphase checkpoint also occurs where the cell checks that the chromosomes are attached to the spindle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are chromosomes made from?

A

Two chromatids joined by a centromere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Why are there two chromatids in a chromosome?

A

Each chromosome has made an identical copy of itself during interphase.

20
Q

What happens to the chromosomes at the end of mitosis?

A

The chromatids end up as one strand chromosomes in the new daughter cells

21
Q

What happens during anaphase?

A

The centromeres divide separating each pair of sister chromatids. The spindles contract pulling chromatids to opposite ends of the cell, centromere first.

22
Q

What happens during telophase?

A

The chromatids reach the opposite poles on the spindle, they uncoil and become long and thin again. The chromatids become chromosomes again and a nuclear envelope forms around each group of chromosomes, so there are two nuclei

23
Q

What happens during cytokinesis in animal cells?

A

The cytoplasm divides and a cleavage furrow forms to divide the cell membrane, forming two daughter cells that are genetically identical to the original cell.

24
Q

When does cytokinesis begin and end?

A

It begins in anaphase and ends in telophase, it’s a separate process to mitosis.

25
Q

What happens during cytokinesis in plant cells?

A

A cell plate forms by microtubules transporting vesicles to the centre of the cell. The vesicles fuse together and a new cell wall is built, separating the cells

26
Q

What does mitosis produce?

A

Two genetically identical diploid cells

27
Q

What does meiosis produce?

A

Four genetically different haploid cells

28
Q

How can you observe the cell cycle?

A

You can stain chromosomes and view them with a microscope.

29
Q

What happens during sexual production?

A

Two gametes join together to form a zygote. This divides and develops into a new organism, meiosis occurs to produce gametes.

30
Q

How many chromosomes do the cells at the end of meiosis have?

A

Half the number of cells, they are haploid. This is because they are gametes

31
Q

What is mitosis 1?

A

Reduction division - it halves the chromosome number.

32
Q

What happens during prophase 1 in meiosis?

A

The chromosomes condense becoming shorter and fatter. They then arrange themselves into homologous pairs, and crossing over occurs. Centrioles start moving to opposite ends of the cell and form spindle fibres, and the nuclear envelope breaks down.

33
Q

What happens during crossing over?

A

Homologous pairs cross over and pair up in meiosis 1. The chromatids twist around each other and bits of chromatids swap over. The chromatids still contain the same genes but have a different combination of alleles

34
Q

What happens in metaphase 1?

A

The homologous pairs line up across the centre of the cell and attach spindle fibres by their centromeres.

35
Q

What happens in anaphase 1?

A

The spindles contract which separate the homologous pairs. One chromosome goes to each end of the cell.

36
Q

What happens in telophase 1?

A

A nuclear envelope forms around each group of chromosomes

37
Q

What happens in cytokinesis one?

A

The cytoplasm divides and two haploid daughter cells are produced.

38
Q

What happens in anaphase 2?

A

The pairs of sister chromatids are separated and each new daughter cell inherits one chromatid from each chromosome. Four haploid daughter cells are produced (gametes)

39
Q

What happens in meiosis 2?

A

The same as mitosis apart from anaphase 2.

40
Q

What two processes in mitosis cause genetic variation?

A

Crossing over of chromatids and independent assortment of chromosomes

41
Q

What happens during independent assortment?

A

Each homologous pair of chromosomes is made up of one maternal and one paternal chromosome. When the homologous pairs line up in metaphase one and are superstates in anaphase one it’s completely random which chromosome from each pair ends up in which daughter cell. This means that the four daughter cells produced have completely different combinations of maternal and paternal chromosomes

42
Q

What are stem cells?

A

Stem cells are a renewing source of undifferentiated cells. They can develop into different types of cells.

43
Q

Where stem cells found in animals?

A

They’re found in embryos and bone marrow. In embryos, the stem cells can differentiate into any type of human cell, but adult stem cells can only differentiate into any type of human cell.

44
Q

What is differentiation?

A

The process by which a cell becomes specialised for its job.

45
Q

What are adult stem cells used for?

A

To replace damaged cells, and to make new skin or blood cells

46
Q

What are stem cells in plants used for?

A

They make new roots and shoots, and plant tissues such as the xylem and phloem.

module two biology (7 decks)

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