Brainscape's Knowledge GenomeTM

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


See full index

BIOL332 > What's in our Genomes > Flashcards

What's in our Genomes Flashcards

1
Q

What percent of the human genome is completed of protein coding genes?

A

1-2% – 1.5% codes for proteins
***It feels like there should be a lot more of genome BUT protein coding genes is really a small portion of the genome
- genome has very few protein coding sequences
- Very few genes in genome
- Small fraction of genome that makes proteins (surprising we think it should be more)

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

Gene

A

Segment of DNA that actually codes for proteoms

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

Central Dogma

A

Flow of information from DNA –> RNA –> Protein

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

Transcription

A

DNA –> RNA

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

Translation

A

RNA –> Protein

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

Genes in genome

A

Gene make up a small portion of our genome – 2% of genome

***26,500 genes in human genome – there are a lot of genes BUT they make up a small portion of the genome

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

What Makes up the genome

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

2% genes
26% Introns
44% Transposable Elements
16% Repetative Sequences
12% Unknown

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

Amount of Introns in genome

A

26% – higher volume than genes

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

Introns

A

Parts of DNA that are transcribed THEN removed from RNA transcription to make mature RNA

**Part of RNA that is removed
**After removed = get mature RNA

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

What is the purpose of Introns?

A
  1. Alternative Splicing (Especially in higher Eukrayotes)
  2. Regulation
  3. To give extra space to protein genes (protects protein coding genes because it makes it less likely that a mutation will be in the protein coding genes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Introns protection

A

Give extra space to protein genes (protects protein coding genes because it makes it less likely that a mutation will be in the protein coding genes

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

Introns Regulation

A

Control of Intron splicing rates can regulate gene expression
- If have transcription ready and hold back on splicing = makes different rates of when genes are expressed

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

Where is alternative splicing found

A

Especially used for higher Eukaryotes

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

Alternative Splicing

A

Reuse DNA – 1 gene = encodes different proteins that can do different things -
***Can create different proteins from one gene

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

Alternative Splicing (process)

A

Body can choose which introns to remove – removes different introns/exons = get similar proteins BUT different
***Can keep some exons or remove others = creates different proteins during splicing process

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

When in process does splicing occur

A

Between transcription and translation

Transcription –> Splicing –> Translation

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

What makes up majority of genome?

A

Transposable elements = held together by Transposable elements

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

Transposable Elements (overall)

A

Selfish Jumping genes – copy themselves and jump to another part of the genome
- Selfish genetic elements OR genomic parasites

***Discovered by Barbra

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

Purpose of Transposable elements

A

Unknown BUT likely NOT junk DNA
***Before they thought it was Junk BUT professor does not think that they are junk

Possibilities:
1. Regulatory
2. Evolutionary
***NOT JUNK – we adapted them over time for a purpose

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

Common Types of Transposable elements

A

SINEs/LINE

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

Regulatory Transposable elements

A

SINE TE – found upstream if ISL1 alters gene expression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

SINE TE

A

Regulatory Transposable elements – found upstream of ISL1 – alters gene expression
***As SINE TE moves = allows gene to be expressed or not

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Upstream

A

In front

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Evolutionary Purpose of Transposable elements

A

Idea = Transposable elements have evolutionary purposes – helps us evolve

Example – During splicing you might have Transposable elements as part of exon that is then translated to proteins = get novel proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Why should Transposable elements be Junk

A

Why would we still have them after evolution –> why would we keep them in and have to replicate more fo DNA than we need

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Repetitive Sequences

A

Sequences that are repeated

28
Q

Heterochromatin

A

Dark band on chromsome –> tightly packed together – HELPS packing

- Typically full of repetitive sequences
29
Q

Purpose of Heterochromatin

A

Helps packing DNA into cell

30
Q

Where can repetative sequences be found?

A

Found in Heterochromatin regions –> manes that repative MUST be important for condensing DNA

31
Q

Types of repetative sequences

A
  1. Short and Sequential
  2. Long and Segmented
32
Q

Short and Sequential Repetitive Sequences

A

Short and sequential nucleotides that repeats

Example – trinucleotode repeat such as CAGCAGCAG –
Other names:
1. Simple repeats SSRs
2. Simple Tandem Repeats (STRs)
3. Microsatalites

***Can include 1, 2, or 3 nucleotide repeats

33
Q

Long and Segmented Repetitive Sequences (overall)

A
  • Can be 10,000 BP long
    • can repeat within same chromsome or between two chromsomes
34
Q

Affect of Long and Segmented Repetitive Sequences

A

Can affect recombination

35
Q

Importance of Long and Segmented Repetitive Sequences

A

Important for condesning DNA – we know this because they are found in Heterochromatin (which is used for condensing DNA)

36
Q

Long and Segmented Repetitive Sequences in Heterochromatin

A

Helps condensing DNA – the Heterochromatin has lots of repetitive sequences + proteins that bind to repetitive sequence that helps condense DNA

37
Q

Genome variation between people

A

ONLY 0.1% is variable between people
***Most of DNA is identical

38
Q

Where is variation found in the genome (in coding or non-coding regions)?

A

More likley in non-coding regions because most of genome is Non-coding BUT variation can be found in both
- Genetic variation is scattered throughout the genome – sometimes it occurs in genes BUT often not
- Often in non-coding because most of DNA is non-coding

39
Q

Where are genes + variation in genome

A

Genes are scattered throughout genome + variation is also scattered

40
Q

Where do phenotypic differences come from?

A

Phenotypic difference = mostly due to difference in coding genes

41
Q

Types of variation between individuals

A
  1. SNPs
  2. CNVs
42
Q

Single Nucleotide Polymorphism

A

SNPs – Single nucleotide base change

43
Q

Amount of SNPs between 2 humans

A

Between any 2 humans have 1 SNO/1000 bp –> means that there are 3-5 Million SNPs/genome (Means that there are many SNP differences between us)

NOTE: 3-5 millions SNPs/genome – genomes is 3 billion BP

44
Q

Where are SNPs found

A

Can be found in coding and non-coding

45
Q

Trend with SNPs

A

Often Bi-allelic – means that there are usually only 2 nucleotides possible
***Makes it easy to talk about population genetics

46
Q

Allele

A

Version of a gene – Non-identical regions
**Can be at ANY locus (Any position) = means that it doesn’t NEED to be coding (Can be in non-coding)
**Non-identical regions = allele

***Relative position might change

47
Q

Non-coding SNPs

A

Very important

48
Q

Copy Number Variations

A

CNVs – means that you have different amounts of nucleotide repeats (

Example: Trinucleotide repeates

49
Q

Importance of CNVs

A
  1. Diseases can occur in Tandem Number repetas occur within important genes
    Example – Huntington’s dieases
  2. Disease can occur if have CNVs at structurally important regions of a chromsome
    Example – Fragile X
50
Q

What causes Huntington’s disease?

A

CAG repeate in gene = get change in protein coding sequence = get phenotypes associated with Huntingtons

51
Q

What causes Fragile X

A

Have CNVs at structurally important regions of the chromosome –> causes region of X chromsome to be unstable = break of peice of X chromsome = lose lots of DNA = disease

52
Q

Where can CNVs occur?

A

Can happen in whole genome –> CAN have no phenotipic affect – often does not cause a problem espcially because most of genome is not protein coding genes

53
Q

Affect of CNV

A

Often does not cause a problem because most of DNA is NOT protein coding genes

54
Q

CNVs between individuals

A

Between ANY 2 humans = have 1500 CNVs

55
Q

Average size of CNVs

A

20,000 bp (20 Kbp)

56
Q

Possible affects CNVs and SNPs on phenotypes

A
  1. Disease –> if in important genes or in important sturctural region
  2. Different proteins being made
  3. Different Phenotypes
  4. Might not be able to make a protein – lack of protein being
  5. Might be adaptive
57
Q

Example of Lack of protein being made

A

Might have lack of protein being made IF have SNP that changes start codon

58
Q

Usual affect of CNVs and SNPs

A

Most CNVs and SNPs are not in protein coding regions (not in genes) = mostly have no affect

59
Q

Example adaptation from CNV

A

Copper resistance in yeast – A lot of yeast live with grapes and pestscides that contain copper are often sprayed on the grapes –> the yeast have evoloved to tolerate higher levels of Copper by repeating copies of copper transporter chain

***CNV that helps YEAST

60
Q

What differs between species?

A
  1. Number of chromsomes
  2. Chromosome size
  3. Types of Introns
  4. Number of genes
  5. Types of genes – there is a lot of homology BUT usually some genes are species specific

***CAN have the same between species BUT these are ALL the same within species

61
Q

Genes between species

A

Usually there is a LOT of homology but usually there are some genes that are species specific

62
Q

Differences within species (differences between humans)

A

Difference is made by SNPs and CNVs

63
Q

Genomes between species

A

Many genome features are shared across species

64
Q

Homology between species

A
  1. Between humans = 100%
  2. Humans and Chimpanzee = 98%
  3. Human and mouse = 92&
  4. Human and fruit fly = 44%
  5. Human and yeast = 26%
  6. Human and a weed = 18%
    ***We are more alike that we might suspect
65
Q

Use of homology between species

A

Model organisms – because we are more alike we can use model organisms

***Model organism are important for genetic studies

66
Q

Homologous genes between organisms

A

Genes from one organism can often replace the function of homologous genes in another organism

BIOL332 (25 decks)

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