cellular control Flashcards

1
Q

what is a mutation

A

random changes in the genetic material (DNA) of a cell that leads to the introduction of variation

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

what is the function of the Lac Operon

A

an example of a regulatory mechanism at the transcriptional level (i.e. a regulatory mechanism that occurs during transcription)

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

what is a gene mutation

A

a random change to the base sequence of DNA

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

where can mutations happen

A
  • somatic cells
  • gametes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

gametes (mutation in gametes)

A
  • present in egg or sperm
  • can be inherited
  • causes cancer family syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

somatic cells (mutation in somatic cells)

A
  • non - gamete tissue
  • cannot be inherited
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the 2 types of mutation

A
  • point mutations/substitutions
  • insertion/deletions (or indel mutations)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is a point mutation/substitution

A

one base pair replaces another. Otherwise known as a substitution.

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

what is insertion/deletion (or indel mutations)

A

one or more nucleotides are inserted, or deleted from a length of DNA, this may cause a frame shift.

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

what is the difference between the coding and template strands in DNA

A
  • nucleotides, add on to a template strand.
  • mRNA, is the same as the coding strand.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is translation

A

mRNA, is used, to put the amino acids in the correct order during protein synthesis.

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

what is silent mutation

A

a mutation where the same amino acid is coded for using a different triplet thus meaning there are no consequences.

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

what is a missense mutation

A

one base change, leads to a different amino acid being made. The impact this had, depends on the amino aid that is being made.

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

what is nonsense mutation

A

one point mutation which leads to a stop codon. Therefore, stopping the production of the polypeptide.

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

what is a frameshift mutation

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

what are 3 categories of mutations

A
  • beneficial
  • neutral
  • harmful
17
Q

what is a beneficial mutation

A

different alleles, e.g. paler skin enables vitamin D to be made whilst black skin has more melatonin thus protecting from skin cancer.

18
Q

what is a neutral mutation

A
  • inability to smell certain flowers
  • different shaped ear lobes
19
Q

what is a harmful mutation

A
  • Duchenne muscular dystrophy (nonsense mutation)
20
Q

what is an activator

A

starts transcription

21
Q

what is a repressor

A

stops/prevents transcription

22
Q

what does the regulatory gene do (repressor)

A

stops transcription

23
Q

what is the function of B galactosidase

A

hydrolyses lactose -> glucose and galactose

24
Q

what is the function of lactose permease

A

allows lactose to enter the bacterial cell

25
why is gene expression so important in eukaryotes
controlling gene expression, is important to ensure the correct proteins are being made by the correct cells.
26
what do transcription factors control
they control which genes, are switched on or off
27
what do transcription factors bind to
specific promotor region
28
what is post transcriptional gene regulation
splicing out non-coding intron regions of transcribed mRNA
29
what is alternative splicing
genes can be spliced in different ways. Therefore length of DNA can encode more than one protein, depending on how it is spliced
30
what is post translational gene regulation
- modifications, to the proteins or amino acids - e.g. adding non protein groups, like lipids or phosphates, forming extra bonds, folding or shortening, modification of cAMP.
31
what is a homeotic gene
a large group of genes, that control anatomical development
32
what is a homeobox sequence
part of the gene. that codes the homeodomain
33
what is the homeodomain sequence
part of a protein, that is shaped in a way, that allows it to bind to DNA and act as a transcription factor.
34
where are homeobox genes found
in plants, animals and fungi.
35
what does the term 'collinearity' mean
hox genes, are activated during development of the embryo. They are expressed, in order, from front to back
36
how are the hox genes regulated
- maternally supplied mRNA, in egg cytoplasm -
37