D2.2 Gene Expression Flashcards

1
Q

Phenotype

A

The functional and structural characteristics of an organism.

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

Genotype

A

All the genetic information of an organism.

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

Gene expression

A

The process of turning genotype into phenotype by protein synthesis.

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

Promoters function

A

A sequence of DNA located upstream of a gene in the 5’ direction, ensure that RNA polymerase transcribes the gene in a 5’ to 3’ direction.

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

Transcription Factors

A

Proteins that bind to specific base sequences of DNA and regulate gene transcription.

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

What happens to mRNA after it is no longer required for translation?

A

It is broken down by nucleases.

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

What are examples of protein synthesis in which DNA degradation regulation is important?

A
  • Casein being produced for ling periods of time.
  • Cyclins that are only needed briefly.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

State the relationship between the length of a poly-A tail and its lifespan:

A
  • Shorter = higher nuclease activity
  • Longer = lower nuclease activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Epigenesis

A

The development of a plant or animal from undifferentiated cells.

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

How does differentiation occur in the context of gene expression control?

A

Activating some genes and deactivating others.

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

Epigenetic tags

A

Chemical modifications of DNA that alter the phenotype of an organism.

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

Genome

A

Whole genetic information of a cell.

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

Transcriptome

A

The entire set of mRNAs transcribed in a cell.

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

Proteome

A

The entire set of proteins produced by a cell.

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

Methylation

A

The replacement of a hydrogen with a methyl group.

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

Role of the methylation of the promoter:

A
  • Prevents the binding of some transcription factors so that RNA polymerase does not transcribe the gene downstream of the promoter and is not expressed (usually adenine and cytosine).
17
Q

Role of methylation in histones of nucleosomes:

A
  • Methyl can be added to an amino acid in histone proteins to activate or deactivate transcription.
18
Q

Epigenome

A

All of the genetic tags of an organism.

19
Q

What do epigenetic tags influence?

A

Gene expression and phenotypes.

20
Q

: How do epigenetic tags change during a cell’s life?

A

They change in response to environmental factors.

21
Q

What happens to epigenetic tags during cell division?

A

They can be passed to daughter cells, helping them perform the same functions.

22
Q

What was previously believed about epigenetic tags during meiosis?

A

They were thought to be removed, leaving a “blank canvas” in zygotes.

23
Q

What recent evidence suggests about epigenetic tags?

A

Some tags are not removed and can be passed to offspring (transgenerational inheritance).

24
Q

How do epigenetic tags differ from base sequences?

A

Epigenetic tags can be easily changed, while base sequences are altered only by mutations.

25
Q

What is an example of transgenerational epigenetic inheritance?

A

1% of epigenetic tags persist to the next generation.

26
Q

Out of the blue

A

An epigenetic tag can prevent a dominant allele from being expressed.

27
Q

What are environmental factors that can affect gene expression

27
Q

Monozygotic Twins

A

Come from one zygote

28
Q

Dizygotic Twins

A

Twins that come from two separately fertilized zygotes. (Share 50% of DNA)

29
Q

How do environmental factors affect gene expression (lactase production):

A
  • Absent: repressor proteins bind to the promoter of the lactase gene to prevent expression.
  • Present: The repressor does not bind to the promotor, so it can bind to the lactase gene and start transcription.
30
Q

How do environmental factors affect gene expression (oestrogen):

A
  • Estrogen binds to a gene that produces progesterone receptor, and the endometrium becomes more responsive to progesterone.