Brainscape's Knowledge GenomeTM

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


See full index

Biology- Topic 8 > control of gene expression > Flashcards

control of gene expression Flashcards

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

gene mutation

A

change in base sequence of DNA
- occurs during DNA replication
- includes addition, deletion, substitution, inversion, duplication and translocation of bases

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

mutagenic agents

A

chemical or radiation that
increases mutation rate

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

addition mutation

A

One extra base is added to the DNA sequence
causes all subsequent codons to be altered (frameshift)

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

deletion mutation

A

One base is deleted in the DNA sequence.
causes all subsequent codons to be altered (frameshift)

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

translocation of bases mutation

A

A section of bases on one chromosome detaches and attaches to a different chromosome

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

substitution mutation

A
  • One base in the DNA sequence is changed
  • no frameshift
  • only one codon changes
  • may have no impact due to degenerate genetic code
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

frameshift

A

A change in all the codons after the point of mutation
each base shifts left or right one position

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

non-functioning protein

A

a protein with a different primary and tertiary structure therefore the shape is changed
- it cannot carry out its function

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

duplication mutation

A

One base is duplicated at least once in the sequence
- causes a frameshift to the right

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

inversion mutation

A

A section of bases detach from the DNA sequence and re-join inverted
- results in different amino acids being coded for in this region

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

benign tumour

A
  • non-cancerous tumour
  • grows large but at a slow rate
  • produce adhesive and are surrounded by a capsule so they cannot spread
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

tumour

A

a mass of cells as a result of uncontrolled cell division
- can be benign or malignant

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

malignant tumour

A
  • cancerous tumour
  • grows rapidly
  • can become unspecialised can metastasise
  • grow projections
  • develop own blood supply
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

cancer

A

Malignant tumours that form due to uncontrolled cell division

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

metastasis

A

cancer cells breaking off from the tumour
- spreading to form secondary tumours in different tissues or organs

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

oncogene

A
  • a mutated version of a proto- oncogene
  • results in constant initiation of DNA replication and mitotic cell division
  • causes tumour formation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How can oestrogen increase the risk of breast cancer?

A
  • Oestrogen is a steroid hormone it binds to a receptor site on a transcriptional factor
  • causing a change in shape
  • so it can bind to the DNA to
  • initiate transcription
  • can result in uncontrolled cell division
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

tumour suppressor genes

A

genes that produce proteins to slow down cell division and cause cell death if DNA copying errors are detected

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

methylation of DNA

A
  • inhibits transcription
  • methyl groups attach to the cytosine base on DNA
  • prevents transcriptional factors from binding
  • condenses the DNA-histone complex
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

epigenetics

A
  • the heritable change in gene function without changing the DNA base sequence
  • caused by changes in the environment
  • can inhibit transcription
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

hypermethylation

A
  • an increased number of methyl groups attached to a gene - results in the gene being deactivated
  • results in cancer if happens to a tumour suppressor gene
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Stem cell

A

undifferentiated cells that can continually divide and become specialised

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

Pluripotent stem cell

A

can differentiate into almost any body cell
occur in embryos

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

Multipotent stem cell

A

can differentiate into a limited number of cells
found in mature mammals e.g in bone marrow

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

Totipotent stem cell

A

can differentiate into any body cell
occur for a limited time in early mammalian embryos

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

Unipotent stem cell

A

can differentiate into one type of cell
found in mature mammals

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

Induced pluripotent
stem cell

A

produced from adult somatic cells
- using protein transcriptional factors
- overcomes ethical issues of using embryonic stem cells

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

Transcriptional factor

A

proteins that can bind to different base sequences on DNA
- initiate transcription of genes

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

What is a vector?

A

a DNA molecule used as a vehicle to carry a DNA fragment e.g. plasmids/viruses

22
Q

Acetylation of histones

A
  • Decreased acetylation inhibits transcription
  • removing acetyl groups makes the histones more positive - this attracts the negative phosphate group on DNA
  • making it harder for the transcriptional factors to bind
23
Q

siRNA

A

small interfering RNA destroys mRNA molecules to prevent translation

24
Q

How can you create a DNA fragment?

A
  • Reverse transcription with reverse transcriptase
  • restriction endonucleases
  • gene machine
24
Q

RNA interference

A

inhibition of the translation of mRNA
the mRNA gets destroyed so it cannot be translated

25
Q

Recombinant DNA technology

A

combining different organisms’ DNA
enable scientists to manipulate and alter genes to improve industrial processes and medical treatment

26
Q

Sequencing projects

A

Reading the full genome of organisms
provides opportunities to screen DNA to identify potential medical problems

27
Q

Reverse transcriptase

A

An enzyme that makes cDNA single-stranded copies of DNA from mRNA

27
Q

Gene machine

A

creates DNA fragments using a computerised machine

28
Q

Restriction endonulceases

A
  • Enzymes that cut up DNA to create fragments
  • cut at specific recognition/restriction sequences
  • results in sticky ends
29
Q

In vivo cloning

A

Creating DNA fragments using bacteria
involves restriction endonulcease enzymes

30
Q

In vitro cloning

A

Using PCR to create a large number of copies of a DNA fragment

31
Q

Uses of PCR

A

Used widely in gene technology to make large numbers of copies of DNA fragments
e.g. forensics, genotyping, cloning, paternity tests, microarrays

32
Q

Describe the PCR process

A
  • increase temperature to 95C to break hydrogen bonds & split DNA into single strands
  • temperature is decreased to 55C so primers can attach
  • DNA polymerase joins complementary nucleotides & makes a new strand
  • temperature increased to 72C (optimum for Taq DNA polymerase)
33
Q

Uses of genetic fingerprinting

A

Forensic science
medical diagnosis
plant/animal breeding
paternity tests

34
Q

What is gel electrophoresis

A

Separation of DNA samples using an electrical voltage
- different lengths of DNA VNTRs are separated

35
Q

Why does the DNA move in gel electrophoresis?

A

DNA is negatively charged and moves towards the positive end of the gel
- the shorter the piece of DNA, the faster and further it moves

36
Q

What is genetic screening?

A

Testing DNA to identify the presence of alleles that can cause/increase the risk of developing a disease

37
Q

What is genetic counselling?

A

a type of social work giving people advice and information following the screening of disease causing alleles

38
Q

What is cDNA?

A

Complementary, single- stranded DNA strands
created by reverse transcriptase

39
Q

What are the advantages of using the gene machine?

A

Very quick
accurate
create intron-free DNA

40
Q

Oligonucleotides

A

Short DNA molecules
used in gene machines to create DNA fragments

40
Q

What are the advantages of using restriction endonculeases?

A

Creates sticky ends on DNA to enable the DNA fragments to join with complementary base pairs

40
Q

What are the advantages of using reverse transcription?

A

Creates intron-free cDNA

41
Q

Sticky ends

A

Exposed staggered ends of bases
palindromic base sequences created by restriction endonuclease enzymes

42
Q

Palindromic sequence

A

sequences of bases that read the same forwards as they do
backwards

43
Q

What are the two methods to amplify DNA?

A

In vivo
in vitro (PCR)

44
Q

Promoter region

A

a sequence of DNA that is the binding site for RNA polymerase to enable transcription to occur

44
Q

Blunt end

A

When a restriction endonuclease cuts the DNA double-strand in the same position
- there is no overhang of bases

45
Q

Terminator region

A
  • added at the end of the gene
  • it causes RNA polymerase to detach and stop transcription
  • to ensure one gene is copied into mRNA at a time
46
Q

Plasmid

A

a small loop of bacterial DNA
- contains only a few genes
- contains the genes for antibiotic resistance

47
Q

Recombinant plasmid

A

a small loop of bacterial DNA with the DNA from another organism inserted into it

48
Q

Transformation

A

the process of getting a plasmid to re-enter a bacterium
- involves calcium ions and temperature shocking

49
Q

How can transformed cells be identified?

A
  • using marker genes
  • antibiotic resistance genes
  • genes coding for fluorescent proteins
  • genes coding for enzymes
50
Q

**

What is a marker gene?

A

genes on the plasmid used to identify which bacteria successfully took up the recombinant plasmid

51
Q

DNA probe

A

short, single-stranded pieces of DNA
- labelled radioactively or fluorescently so that they can be identified

52
Q

DNA hybridisation

A
  • DNA is heated to separate the double helix into single strands
  • it is then mixed with complementary sequences of single-stranded DNA
  • it is then cooled so complementary strands will anneal
53
Q

Personalised medicine

A

screening for the presence of particular alleles
to select medicines and personalise health advice based on your genotype

54
Q

VNTRs

A

variable number tandem repeats sequences of bases in introns
unique to each person

55
Q

How can DNA samples be collected?

A

From blood, body cells or hair follicles

56
Q

How is DNA extracted from cells so that it can be examined?

A

cell fractionation and ultracentrifugation

57
Q

How is DNA digested in genetic fingerprinting?

A
  • Restriction endonucleases are added to cut the DNA into smaller fragments
  • enzymes that cut close to the target VNTRs are added
57
Q

Why can the genome not be easily translated into the proteome in complex organisms?

A

due to the presence of non- coding DNA and regulatory genes

58
Q

What is the role of DNA ligase in making recombinant DNA?

A

used to stick the DNA fragment to create recombinant DNA

Biology- Topic 8 (2 decks)

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