Brainscape's Knowledge GenomeTM

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


See full index

Biology > nab revision unit 1 > Flashcards

nab revision unit 1 Flashcards

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

what happens during differentiation?

A

unspecialised cells become adapted or altered to perform a specific function as part of a permenant tissue

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

why cant a specialised cell develop into different types of cells?

A

the genes needed are switched off and cant be turned back on

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

what are stem cells?

A

relatively unspecialised cells which can develop into different types of cells because most of their genes are still switched on

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

what are some therapeutic uses of stem cells?

A

corneal grafts, bone marrow transplants and skin grafts

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

what are somatic cells?

A

differentiated cells that form different types of body tissue e.g. blood, bone, muscle, nerve

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

what are germline cells?

A

the gametes and the cells that produce the gametes

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

what are cancer cells?

A

cells which do no respond to normal regulatory signals that would instruct them to stop dividing when necessary

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

how is a tumour formed?

A

when cancer cells continue to reproduce and form a mass of abnormal cells

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

how are secondary tumours formed?

A

when cells from a tumour detach from their neighbours and spread throughout the body

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

how many strands does dna consist of?

A

2

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

what are the repeating units in dna called?

A

nucleotides

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

what is the nucleotide made up of?

A

phosphate, deoxyribose sugar and a organic base

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

what is the backbone of each dna strand made up of

A

deoxyribose and phosphate

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

how are the strands held together?

A

weak hydrogen bonds between the bases

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

what is the structure of dna?

A

the strands run anti-parallel to each other, double helix structure

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

how are chromosomes formed?

A

dna is tightly coiled and packaged around bundles of protein which coil to form chromosomes

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

replication stage 1

A

dna double helix unwinds

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

replication stage 2

A

weak hydrogen bonds break causing the 2 strands to seperate

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

replication stage 3

A

free dna nucleotide joins complimentary pair on open strand

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

replication stage 4

A

weak hydrogen bonds reform between base pairs

21
Q

replication stage 5

A

strong chemical bond forms between both nucleotides controlled by the enzyme dna polymerase

22
Q

replication stage 6

A

newly formed daughter dna (identical to original) begins to wind into double helix

23
Q

what does dna polymerase do?

A

it can only add nucleotides to the free 3’ end of a growing strand and needs a primer to start things off

24
Q

what is a primer?

A

a piece of single-stranded dna which is complementary to a specific target sequence on the strand being replicated

25
Q

how is the 5’ end of dna replicated?

A

the strand with the 5’ end exposed is replicated in fragments starting at the 3’ end, they are then joined together by then enzyme ligase

26
Q

what is a mRNA molecule?

A

a mRNA molecule carries the code from the dna in the nucleus to the ribosomes. mRNA is a single strand of nucleorides, which has no folding along its length, and therefore can have no base pairing

27
Q

what is a tRNA molecule?

A

a tRNA molecule carries a specific amino acid to the ribosomes. tRNA is a single strand of nucleotides which folds back on itself to make a 3D shape. base pairing occurs

28
Q

what is a substitution mutation?

A

one nucleotide swapped for another, so only one amino acid changed

29
Q

what is a insertion mutation?

A

one nucleotide added, sequence wrong from then on, so all amino acids altered from then on (frameshift)

30
Q

what is a deletion mutation?

A

one nucleotide lost, sequence wrong from then on, so all amino acids altered from then on (frameshift)

31
Q

what is a splice-site mutation?

A

a mutation occuring at a splice-site, which results in an intron remaining attached to the mRNA

32
Q

what is a missense mutation?

A

following a substitution, the altered codon codes for an amino acid that still makes sense but not the original sense

33
Q

what is a nonsense mutation?

A

an amino acid is substituted with a stop codon

34
Q

what is pcr used for?

A

to amplify (make copies of) a specific segment of DNA

35
Q

what does the amplification of dna involve?

A

the use of primers

36
Q

what is stage 1 of pcr?

A

melting; dna is heated to seperate the strands

37
Q

what is stage 2 of pcr?

A

annealing; dna is cooled for primer binding

38
Q

what is stage 3 of pcr?

A

extending; dna is reheated to allow heat tolerant dna polymerase to manufacture complementary strands

39
Q

what are inhibitors?

A

chemicals which slow down or stop an enzyme controlled reaction (competitive or non-competitive)

40
Q

what do competitive inhibitors do?

A

interfere with the active site of the enzyme so the substrate cannot bind

41
Q

what do non-competitve inhibitors do?

A

change the shape of the enzyme so it cannot bind to the substrate

42
Q

comparitive effects of increasing substrate concentration in the presence of inhibitors when enzyme concentration is limited

A

competitive; effect depends on relative concentration of substrate and inhibitor
non-competitive; effect depends only on concentration of inhibitor

43
Q

what happens in an anabolic pathway?

A

small molecules are assembled into large ones. energy is required

44
Q

what happens in a catabolic pathway?

A

large molecules are broken down into small ones. energy is released

45
Q

what does the enzyme phosphofruktokinase do in stage 1 of respiration?

A

makes the intermediate compound irreversible and continues the process of glycolysis and is known as the key regulatory point

46
Q

what do dehydrogenase enzymes do?

A

remove hydrogen ions from substrate

47
Q

what are slow twitch muscle fibres good for?

A

endurance activities e.g. rowing, cycling and long distance running

48
Q

what are fast twitch muscle fibres good for?

A

bursts of energy e.g. sprinting and weightlifting

Biology (1 decks)

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