Brainscape's Knowledge GenomeTM

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


See full index

A level biology > 2.1.6 Cell division > Flashcards

2.1.6 Cell division Flashcards

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

What is the name of the process that the cell is in during its majority of time?

A

interphase

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

What does interphase include?

A

G1, S and G2

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

What occurs in G1?

A

growth of cells;
growth of organelles;
increase in no. of organelles;
proteinsynthesis

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

What occurs in G2?

A

growth of cells;
growth of organelles;
increase in no. of organelles;
proteinsynthesis;
spindle fibres begin to form;

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

What occurs in the S phase?

A

DNA replication = must occur so that the daughter cells have the same/identical DNA and a full copy of DNA

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

What are the uses of mitosis?

A

growth of organism
repair of tissues
replacement of old cells
asexual reproduction

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

What occurs in G0 and where is it located?

A

after the mitosis stage
enters when:
- cell is fully differentiated
- DNA in the cell is damage = repair DNA

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

What occurs in G1 and where is it located?

A

occurs between G1 and S phase
enters when:
- check to see if all the chemicals needed are met if not = enters G0

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

What occurs in G2 and where is it located?

A

after the G2 stage
enters when:
- checks for mutation in DNA
- daughter cells may not recieved identical genetic info
- proteins may no function = enter G0

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

What occurs at the metaphase checkpoint?

A

checks to see if the spindle fibres have aligned correctly

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

What are the stages of mitosis?

A

prophase
metaphase
anaphase
telophase

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

What occurs in prophase?

A

nuclear envelope breaks down;
chromosomes condense;
spindle fibres attach to the centromere of the chromosomes;

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

How do the chromosomes condense?

A

DNA is wrapped around histone proteins = visible by microscope

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

What occurs in metaphase?

A

chromosomes line up at the equator of the cell;
spindle fibres attach to the centromeres of the chromosomes

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

What occurs during anaphase?

A

chromatids are pulled to opposite poles of the cell;
by the spindle fibres contracting;
centromere breaks;

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

What occurs during telophase?

A

nuclear envelope reforms;
chromosomes uncoil;
cell surface membrane undergoes cytokinesis;
spindle fibres break down;

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

What occurs during cytoskinesis?

A

the cell pinches into two, forming 2 genetically identical cells

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

How does cytokinesis occurs in plants?

A

cell plates form;
by the golgi apparatus and vesicles = assemble at the equator and deposit contents;
some vesicles make connecting channels = plasmodesmata through new cell wall

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

What experiment can we use to prepare microscope slide to observe mitosis?

A

root tip squash

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

PAG; Why do you head the plant sample in acid?

A

to break down the cell wall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

PAG; Why do you stain the sample?

A

provides contrast;
makes chromosomes more visible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

PAG; why is it important to ‘squash’ the sample?

A

to make it as thin as possible = light can pass through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What does meiosis produce?

A

non-genetically identical daughter cells;
gametes;
haploid;

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are homologous chromosomes?

A

chromosomes that have;
- same shape and size
- centromere in the same position
- same genes in the same position on chromosomes
- one maternal one paternal

25
Q

What occurs during prophase I ?

A

chromosomes condense;
homologous chromosomes pair up to form bivalents;
chromatids in each bivalent break off and form chiasma = crossing over;
nuclear envelope breaks down;
spindle fibres form;

26
Q

What occurs during metaphase 1 ?

A

spindle fibres attack to the centromeres of chromosomes;
bivalents move to the equator of the cell;
independent assortment occurs;
(orientation of each bivalent is random)

27
Q

What occurs during anaphase I ?

A

spindle fibres contract;
separate bivalent to opposite poles;
each chromosomes still contains two chromotids;

28
Q

What occurs during telophase I?

A

nuclear membrane reforms;
chromosomes uncoil and form two nuclei = each has half the number of chromosomes than the beginning

29
Q

What is different in prophase 2 than prophase 1?

A

no crossing over

30
Q

What is the same in metaphase 1 and 2?

A

independent assortment still occurs

31
Q

What occurs in anaphase 2 that doesn’t occur in anaphase I?

A

centromere breaks

32
Q

How many cells does meiosis produce?

A

4 genetically different daughter cells

33
Q

Why is it important that gametes are haploid?

A

when they become fertilised = becomes a diploid zygote

34
Q

How does genetic variation occur in meiosis?

A

prophase I = crossing over
metaphase I : independent assortment
metaphase II: independent assortment

35
Q

How are erythrocytes specialised?

A

small - fit through capillaries
no nucleus/organelles - space for heamoglobin = carry large volume of oxygen
biconcave shape = increases SA:V = gas exchange more efficent/takes up oxygen quickly

36
Q

How are neutrophils specialised?

A

lobed nucleus
granular cytoplasm = lots of lysosomes = contain digestive enzymes
flexible shape = enables movement through tissues
membrane bound receptors = recognise material that needs to be destroyed

37
Q

How are squamous epithelial cells specialised?

A

used to line blood vessels
flattened smooth, thin surface = short diffusion distance = gas exchange is efficient

38
Q

How are ciliated epithelial cells specialised?

A

column shaped cells
cilia wave in a synchronised rhythm = move more mucus that are secreted by goblet cells

39
Q

How are sperm cells specialised?

A

lots of mitochondria = movement
acrosome = digestive enzymes = penetrate egg
shape = streamlines = aid movement
contains half no. of chromosomes = when fertilised = diploid zygotes

40
Q

How are palisade cells specialised?

A

long think and packed
contain chloroplast = absorb photons of light for photosynthesis
starch grains = store products of photosynthesis
spongy mesophyll = air space = air circulation

41
Q

How are root hair cells specialised?

A

absorb water and mineral ions through soil
long hair extensions = increase SA
thin walls = efficient exchange
cytoplasm = extra mitochondria for ATP for active transport

42
Q

What is a tissue?

A

same type of cells working together for the same function

43
Q

Give 4 examples of tissues and where they are found?

A

epithelial = line organs to separate
connective = support and structure
muscle = contract
nerve = conduct electrical signals

44
Q

What are organs?

A

group of tissues working together for the same function

45
Q

What is an organ system?

A

made up of 2 or more organs working together to perform a life function

46
Q

How do cartilage and muscle tissue work together in the body?

A

cartilage = holds the trachea open under negative
muscle = contract to constrict airway

= controls ventilation in the lungs

47
Q

What are stem cells?

A

undifferentiated cells
that can differentiate into any cell type
via mitosis

48
Q

What are totipotent stem cells?

A

can differentiate into any body and extra embryonic cell e.g placenta/umbilical cord

49
Q

what are pluripotent stem cells?

A

taken from the blastocyst
can form different body cells
cant form extra embryonic cells

50
Q

What ate multipotent stem cells?

A

found in adults: bone marrow/ribs
bane marry = haematopoietic
can form more than one type/limited

51
Q

How are erythrocytes produced from multipotent stem cells?

A

stem cell would need to remove nucleus
produce lots of haemoglobin

52
Q

How are neutrophils produced from multipotent stem cells?

A

stem cell changes nucleus to lobed nucleus
produce lots of lysosomes

53
Q

Where are stem cells found in plant?

A

vascular cambium = meristem

54
Q

How are xylem cells formed?

A

walls are deposited with lignin = provides strength against negative pressure
cell dies
creates hollow tube
limits lateral movement of water
allows adhesion
also has pits = allows lateral movement of water

55
Q

How are phloem vessels created?

A

sieve tube elements = loose nucleus and organelles
companion cells = metabolically active to provide ATP
plasmodesmata

56
Q

What are the potential uses of stem cells?

A
57
Q

How are stem cells used in medicine?

A

bone marrow = leukaemia
repair spinal cords in rats
treat mice with type 1 diabetes
Alzhiemers disease

58
Q

How can stem cells be used in the future?

A

study what happens when differentiation goes wrong

see if they can re-enable differentation and growth in adults

A level biology (17 decks)

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