Brainscape's Knowledge GenomeTM

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


See full index

Biology Paper 2 content > Topic 8 > Flashcards

Topic 8 Flashcards

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

In Vitro Cloning

A

when gene copies are made outside of a living organism using PCR

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

In Vivo cloning

A

when gene copies are made within a living organism

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

A vector

A

something thats used to transfer DNA into a cell (can be a plasmid or a bacteriophage- a virus that infects bacteria)

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

What two things stick the DNA fragment and vector DNA together during In Vivo cloning

A

restriction endonucleases and DNA ligase (an enzyme)

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

3 methods of making DNA fragments

A
  • Gene Machine
  • Reverse transcriptase
  • Restriction endonuclease enzymes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Restriction endonucleases

A

enzymes that recognise palindromic sequences of DNA and cut the DNA at these places

this can be used to seperate a part of DNA if it has palindromic sequences either side of it

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

sticky ends

A

small tails of unpaired bases at the end of DNA fragments- makes it easier for them to join together because of complimentary base pairing

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

Reverse transcriptase

A

makes cDNA from an mRNA fragment

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

How is cDNA made using reverse transcriptase?

A
  • mRNA is isolated from other cells
  • mRNA mixed with free nucleotides and reverse transcriptase
  • reverse transcriptase uses mRNA as a tamplate to create a complimentary cDNA strand
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

cDNA

A

complementary DNA

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

mRNA

A

messenger RNA

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

Palindromic sequence of nucleotides

A

antiparallel base pairs- they read the same in the opposite direction

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

Recombinant DNA technology

A

transferring a DNA fragment from one organism to another

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

Why is recombinant DNA technology able to work?

A

genetic code is universal and transcription/translation mechanisms are very simmilar

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

How does a gene machine create DNA fragments?

A
  • required sequence is designed
  • first nucleotide is attaches to a support eg) bead
  • Nucleotides added one at a time, with addition of protecting groups- to ensure nucleotides join at correct point and avoid unwanted branching
  • Olingonucleotides (20 nucleotides long) are formed, then joined together to make longer DNA strand
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

6 types of mutation

A
  • Addition
  • Deletion
  • Susbtituton
  • Duplication
  • Inversion
  • Translocation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Degenerate nature of genetic code

A

some amino acids are coded for by more than one DNA triplet - not all mutations will result in a change of amino acid produced

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

Framshift mutations

A

additions, deletions and duplications

almost always cause a change to the polypeptide produced because all base triplets that follow the mutation are shifted

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

Mutagenic agents

A

factors that increase the rate of mutations eg) UV rays, ionising radiation, chemicals and viruses

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

3 ways mutagenic agents can alter rate of mutations

A

1) Acting as a base- changing the sequence
2) Altering bases
3) Changing structure of DNA- causing problems during replication

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

aquired mutations

A

mutations that occur after fertilisation eg) adulthood

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

tumour

A

a mass of abnormal calls caused by uncontrolled cell division (by mitosis)

23
Q

two types of gene that control cell division

A
  • tumour supressor genes

- proto-oncogenes

24
Q

tumour supressor genes

A

when working properly, slow cell division by producing protiens that stop cells dividing (or cause them to self-destruct)

25
Q

Proto-oncogenes

A

stimulate cell division by producing protiens that make cells divide

26
Q

oncogene

A

a mutated proto-oncogene- stimulates cell to divide uncontrollably resulting in a tumour

27
Q

two types of tumour

A

Maliginant- cancers, grow rapidly, destroy surrounding tissue, spread through bloodstream and lymphatic system

Benign- not cancerous, grow slower and covered in fibrous tissue, often harmless but can cause blockages and later become malignant

28
Q

How tumour cells differ from healthy cells

A
  • Nucleus is darker and larger
  • irregular shape
  • dont produce protiens needed to function properly
  • different surface antigens
  • dont respond to growth regulating processes
  • mitosis occurs more frequently
29
Q

Methylation

A

adding a methyl group onto a molecule

important in regulating gene expression, can determine when a gene is transcribed and translated

30
Q

hypermethylation

A

when methylation occurs too much and causes tumours to grown from cancer related genes

31
Q

hypomethylation

A

when methylation occurs too little so tumours can form due to cancer-related genes

32
Q

what can cause increased exposure to oestrogen

A
  • starting periods earlier
  • starting menopause later
  • taking oestrogen containing drugs
33
Q

How could oestrogen contribute to breast cancer?

A
  • stimulates breast cells to divide and replicate- increasing chance of mutation
  • if cells do become cancerous- they will grow mor quickly
  • may be able to introcude mutations directly into the cells of certain breast tissue
34
Q

Risk factors for cancer

A

Genetic:
- some cancers are linked with specific inherited alleles

Enviromental factors:
-radiation, smoking, alcohol, high-fat diet

35
Q

what are stem cells?

A

undifferentiated body cells that can develop into different types of cell

36
Q

totipotent stem cells

A

can develop into any type of body cell, present in first divisions of an embryo

37
Q

pluripotent stem cells

A

after few divisions of embryo

can still develop into any body cell, but not placenta

38
Q

multipotent stem cells

A

can differentiate into a few types of body cell eg) how blood cells can form from bone marrow

39
Q

unipotent stem cells

A

can only differentiate into one type of cell

40
Q

How do stem cells become specialised?

A
  • certain genes are switched on/off
  • the mRNA is transcribed and translated into protiens
  • these proties modify the cell, allowing it to become modified for its specific function
41
Q

cardiomyocytes

A

heart muscle cells that make up a lot of tissue in the heart. were thought to be unable to divide but now its thought that they can regenerate from a small group of unipotent stem cells in the heart

(scientists aren’t completly agreed on it)

42
Q

Bone Marrow transplant

A

bone marrow contains stem cells that can differentiate into any type of blood cell (multipotent)
can be used to replace bone marrow in patients that produce faulty blood cells
to treat Lukemia, lymphoma and genetic disorders

43
Q

ethical considerations of stem cell treatments

A

stem cells from embryos involves the descruction of an embryo that some believe has the right to life

some people have fewer objections to egg cells before fertilisation as they wouldnt survive much longer anyway

some believe only the stem cells of adults should be used, as it doesnt destroy an embryo

44
Q

Benefits of stem cell therapies

A
  • save many lives
  • possible to make stem cells identical to an induviduals own cells, so organs and tissues can be made that arent rejected from the body
  • improve quality of life for many people eg) blind people could see
45
Q

Transcription factors

A

protien molecules that control the transcription of genes

46
Q

activators

A

transcription factors that stimulate/increase rate of transcription

47
Q

repressors

A

transcription factors that decrease/ prevent transcription of a gene

48
Q

RNAi

A

effects gene expression in Eukaryotes

small, double stranded RNA molecule that stops mRNA from target genes being transcribed into a protien

49
Q

epigenetic control

A

controlles whether a gene is transcribed or not (switched on/off) through the attachment/removal of chemical groups too/from histone protiens or DNA

alter how easy it is for enzymes and protiens needed for transcription/translation to reach the DNA and interact with it

50
Q

Two epigenetic mechanisms used to control gene expression

A
  • Increased methylation of DNA- attach to CpG site and changes DNA structure so trancriptional machinery cannot interact
  • Decreased actylation of Histones- removing acetyl groups and DNA wrapped around histones becomes highly condensed so transcriptional machinery cannot physically access DNA strand
51
Q

transformed cells

A

host cells that take up the vector containing genes of interest

52
Q

What percentage of host cells take up the vector and its DNA?

A

approx 5%

53
Q

what type of genes identify transformed cells during in vivo cloning

A

Marker genes- they are inserted into vectors, so any transformed cells will also contain the marker gene

54
Q

Stages of In Vivo cloning?

A

1) Making recombinant DNA
2) Transforming cells
3) Identifying transformed cells
4) Producing protiens

Biology Paper 2 content (2 decks)

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