Mitosis

Question 1

Describe the cell cycle as a regulated process in which cells divide into two identical daughter cells

Answer 1

https: //www.physicsandmathstutor.com/pdf-pages/?pdf=https%3A%2F%2Fpmt.physicsandmathstutor.com%2Fdownload%2FBiology%2FA-level%2FNotes%2FEdexcel-B%2F02-Cells-Viruses-and-Reproduction-of-Living-Things%2FFlashcards%2FFlashcards%2520-%2520Topic%25202.3%2520Eukaryotic%2520Cell%2520Cycle%2520and%2520Divison%2520-%2520Edexcel%2520(B)%2520Biology%2520A-level.pdf#
https: //www.thesciencehive.co.uk/the-cell-cycle-mitosis-and-meiosis-a-level

Question 2

Describe the three main stages of the cell cyle as interphase, mitosis and cytokinesis

Answer 2

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Question 3

Explain what happens to the genetic material during the cell cycle

Answer 3

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Question 4

G1

Answer 4

The tuim ebtween the end of the prvious round of mitosis and the start of chromosome duplication. THe cell assimilates materials, grows and develops.

Question 5

S

Answer 5

The stage when the chromosomes replicate and become double stranded chromatids

Question 6

G2

Answer 6

The time that the organelles and other materials needed for cell division are synthsised

Question 7

M

Answer 7

When the cells are actively dividing

Question 8

c

Answer 8

The new cells seperate

Question 9

What are cyclins

Answer 9

Small p0roteins which build up during interphase and are involved in the control of the cell cycle by their attachment to cyclin dependant kinases

Question 10

Cyclin dependant kinases

Answer 10

Enzymes involved in the control of teh cell cycle by phsophyrylatinfg other proteins, actvtaed by attachemnt to cyclins

Question 11

Define interphase

Answer 11

The period between active cell divisomn when cells increase their size and mass, replicate their DNA and carry out normal metabolic processes

Question 12

Prophase

Answer 12

The chromosomes are coiled up and consist of daughter chromatids joined by the centromere. The nucleolus breaks down

Question 13

Metaphse

Answer 13

The spindle fibres orms and the chromatids line up on the metaphase plate

Question 14

Anapahse

Answer 14

The cntromeres splut so chromatids become new chromsomes. They are moved to opposite poles of the cell, centromere first. by contractions of teh psindle fibre

Question 15

Telophase

Answer 15

The nucelar membrnae forms around the two sets of chromosomes, the chromosomes unravel and the spindle fibres break down

Question 16

A cell divides by mitosis once every two minuetes. Calculate the number of identical cells after 10 minuetes

Answer 16

10 divided by 2 = 5
5 Cell division have taken place
2 to teh power of 5 = 32

Question 17

Sporulation

Answer 17

Process involving mitosis in the production of asexual spores that can grow into new individuals

Question 18

Regenration

Answer 18

The use of mitosis to regrow a body part that has been lost

Question 19

Fragmentation

Answer 19

The use of mitosis to regenerate a whole organism from a fragemnt of teh original

Question 20

Budding

Answer 20

The production by mitosis of an outgrowth from the parent organism that develops into a small independent organism

Question 21

Vegative propagation

Answer 21

The process by which a plant forms a strcuture by mitosis that devlops into a fully differentiated, genetically identical new plant

Question 22

Parthenogensis

Answer 22

An unfertilised egg cell develops into a new individual

Question 23

Asexual reproduction

Answer 23

Involves only one parent individual and it results in genetically idenitcal individuals or clones

Question 24

Binary Fission

Answer 24

The splitting of one indivudla to form two new individuals

Question 25

Explain the imrpotance of mitosis in growth and repair

Answer 25

Growth: when 2 haploid cells fuse together, the diploid cell has all the genetic info
needed to resemble its parents, all cells grown from this need to possess the same info.
- Repair: if cells are damaged or die it’s important that the new cells have an identical
structure and function to those lost.

Question 26

Grwoth in plants

Answer 26

Mitosis continues trhoughout the plants life. It takes place in the meristem whihc are located just behind the tip of the stem or root. After the cells have divided they absorb water into their vacuoles and elongate rapidly before the cellulose cell wall becomes rigid.