Brainscape's Knowledge GenomeTM

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


See full index

Unit 1 Advanced higher Biology > Protein Control of cell division > Flashcards

Protein Control of cell division Flashcards

Complete

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

Cytoskeleton

A
  • Dynamic Intricate network of thread like filaments that fills cytoplasm
  • Consists of different protein structures including microtubules
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What gives mechanical support and shape to cells

A

Cytoskeleton

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

Microtubules

A

Hollow cylinders composed of the protein tubulin
Radiate from MTOC/centrosome

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

Cytoskeleton is responsible for and microtubules control

A

Movement of organelles and chromosomes within it

Microtubules control cytokinesis

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

Formation and breakdown of microtubules

A

Polymeristaion and depolymeristaion

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

Why does mitosis require remodelling of the cytoskeleton

A

Because in mitosis microtubules form the spindle fibres which are active during mitosis, to move chromosomes and separate chromatids.

Microtubules must be dissembled and reassembled

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

Microtubules provide a

A

Framework for attatching
- organelles
- ribosome subunits
- vesicles
- and even molecules,

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

Dynamic nature of Cytoskeleton

A
  • Continually changing to provide support and movement within a cell
  • ## Microtubules can break and reform(controlled by centrosome)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Centrosome

A

Structure involved in cell division.
- duplicates in cell division, the two centrosomes move to opposite ends of the cell.
- Micro tubules come from here
- contains centriols

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

Centriole

A

Helps to arrange the microtubules that move chromosomes during cell division.

Soeach daughter cell recieves right number of chromosomes

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

Cell cycle

A

Consists of
Interphase and Mitosis

Cell grows until it reaches its critical mass, then divides to produce 2

daughter cells

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

Interphase

A

Involves growth and DNA synthesis and can be divided into 3 sub phases=
G1
S
G2.

Lasts 80% of the cell cycle

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

G1

A

First period of cell growth stage. Cell wont divide until it has doubled in size.

Many extra cell components are also synthesised

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

S (synthesis)

A

DNA replication occurs - chromosomes replicate to form two chromatids held together at centromere,

Centrioles duplicate

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

MTOC in mitosis

what it normally does

A

Normally controls the cytoskeleton
but during mitosis **cytoskelton breaks down **and Microtubules are reassembled to form spindle

(centrosome)

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

G2

A

A further growth phase to prepare for mitosis.

Sufficient reserves of ATP built up to last cell through rest of cycle.

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

3 active processes taking place during Interphase

A
  • Cell growth
  • Replication of DNA
  • Protein Synthesis of organelles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Mitosis

consists of

A

Consists of Prophase Metaphase Anaphase Telophase.

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

Prophase

A
  • Dna Condenses into chromosomes consisting of two sister chromatids.
  • Nuclear membrane breaks down
  • Spindle microtubules extend from MTOC by polymerisation
20
Q

Metaphase

A

Chromosomes align at the metaphase plate

21
Q

Anaphase

A

As spindle microtubules shorten by depolymerisation, sister chromatids are separated, and CHROMOSOMES pulled to opposite poles

22
Q

Telophase

A

Chromosomes decondense and nuclear membrane forms around them.

23
Q

What is mitosis controlled by?

A

Controlled and regulated by proteins, and checkpoints

24
Q

what are

Checkpoints

A

**Mechanisms **within cell cycle that asses condition of cell during cycle
Will halt progression to next phase until requirements are met

25
Q

When are checkpoints during cell cycle

A
  • near the end of G1
  • at the G2/M transition
  • and during metaphase
26
Q

Cyclin Proteins

A

**Accumulate **during cell growth.
Involved in regulating cell cycle.
They combine with Cdk’s and activate them

27
Q

Cdk

A

Cyclin dependent kinases

Respitory enzymes

28
Q

Active Cdk/cyclin complexes

When sufficient phosphortylation reached

A

Phosphorylate proteins that regulate cell cycle progression

(so cell cycle can continue)

If sufficient phosphorylation reached, progression occurs

29
Q

G1 Checkpoint

Cyclin/cdk process

A
  1. Increasing cell size accumulates G1 cyclin proteins
  2. Cdks combine
  3. active cyclin/cdk complex formed
  4. phosphorylation of proteins by complex
  5. Phosphorylation threshold reached
  6. Pass checkpoint to next stage
30
Q

G1 Checkpoint

Retinablastoma protein

is a

At G1 checkpoint

A

Transcription inhibitor factor.
Inhibits transcription of genes that code for proteins needed for DNA replication at G1 checkpoint

(prevents progression of cell cycle, tumour supressor protein)

31
Q

G1 checkpoint

Phosphorylation of retinablastoma

A

it can no longer bind to the dna

Allows transcription of genes that code for protein needed for DNA repli

so Cells progress from G1 to S

32
Q

G1 checkpoint

active RB

A
  • Not phosphorylated, transcription inhibition occurs
  • No further growth of cell, so cell cycle halts at G1
33
Q

G1 checkpoint

Inactive RB

A

Rb Has been phosphorylated,
- less trancription inhibition
- So growth occurs and progresses to S phase

34
Q

what is assessed

AT the G2 Checkpoint

A

sucess of dna replication and any damage to dna is assessed

35
Q

If dna damage is present during G2 checkpoint

A

Activation of several proteins including p53 is triggered

36
Q

p53

A

Can stimulate DNA repair
Arrest the cell cycle
Or cause cell death

37
Q

Metaphase checkpoint

controls

A

Controls progression from metaphase to anaphase

Progression is halted until chromosomes are alligned correctly on the metaphase plate and attatched to the spindle microtubules

38
Q

Uncrontoled reduction and increase in rate of cell cycle

A

Reduction= May result in degeerative diseases
Increase= may result in tumour formation

39
Q

What is a

Proto-oncogene

A

A normal gene, usually involved in the control of cell growth or divison

It can mutate!!! To form a tumour promoting oncogene

40
Q

Ccontrol of

Apoptosis

triggered by

A

Triggered by cell death signals that can be external or internal

41
Q

Production of cell death signal molecules from

Lymphocytes and Dna damage

A

lymphocytes= Example of external death signals
DNA damage= Internal

42
Q

External Death signal molecules

A

Bind to a surface receptor protein and trigger a protein cascacde within the cytoplasm

43
Q

What causes activation of p53

tumour supressor protein

A

Internal death signals
(dnadamage)

44
Q

All Death signals cause

A

Activation of caspases
A type of protease enzyme

That cause destruction of the cell

45
Q

WHat is

Apoptosis essential during

A
  • Development of an organism to remove cells that arent required as development progresses
  • or during metamorphosis
46
Q

What happens in the

ABsence of growth factors

A

Cells may initiate apoptosis

Unit 1 Advanced higher Biology (8 decks)

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