Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Developmental Biology > Lecture 3: Genes and Development - Mechanism of Cell Differentiation > Flashcards

Lecture 3: Genes and Development - Mechanism of Cell Differentiation Flashcards

1
Q
  1. What principle states that all cells in an organism contain the same set of genes?
A

Genomic Equivalence

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

How can different cells develop into specialized types despite having identical DNA?

A

Cell Differentiation

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

Give examples of experiments in genomic equivalence: (3)

A
  • Spemann’s Experiment
  • Briggs & King’s Experiment
  • Wolffian Regeneration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which experiment demonstrated nuclear potential in early embryonic development?

A

Spemann’s Experiment

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

Which experiment showed that differentiated cells still retain genetic information?

A

Briggs & King’s Experiment

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

What provides evidence for cellular regeneration and genetic consistency?

A

Wolffian Regeneration

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

What principle states that not all genes are active in every cell at all times?

A

Selective Gene Expression

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

What is the concept that different cells express different genes based on their function and developmental stage?

A

Differential Gene Expression

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

Give the four (4) levels of control that a eukaryotic cell has:

A
  1. Differential Gene Transcription
  2. Selective RNA Processing
  3. Selective mRNA Translation
  4. Differential Protein Modification
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Enumerate the levels of DNA packing from least to most condensed. (6)

A
  1. DNA Double Helix
  2. Nucleosome (“Beads on a String”)
  3. Solenoid (30 nm chromatin fiber)
  4. Looped Chromosome
  5. Condensed Chromosome
  6. Mitotic Chromosome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the first level of DNA packing?

A

DNA Double Helix

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

What structure in chromatin is described as “beads on a string”?

A

Nucleosome

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

What is the 30 nm chromatin fiber of packed nucleosomes called?

A

Solenoid

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

What structure represents a section of the chromosome in an extended form?

A

Looped Chromosome

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

What is a more compacted section of the chromosome called?

A

Condensed Chromosome

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

What is the fully condensed chromosome seen in mitosis?

A

Mitotic Chromosome

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

What was the main objective of the Human Genome Project?

A

Physically map the entire human genome (~3 billion base pairs)

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

When was the Human Genome Project launched? (month/year)

A

October 1990

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

When was the Human Genome Project completed? (month/year)

A

April 2003

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q
  1. How long was the Human Genome Project originally planned to take?
  2. How long did it actually take to complete the Human Genome Project?
A
  1. 15 years
  2. 13 years
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Who led the initial phase of the Human Genome Project?

A

Dr. James Watson

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

Who led the Human Genome Project from 1993?

A

Dr. Francis S. Collins

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

Which organizations led the Human Genome Project?

A

International Human Genome Sequencing Consortium, NHGRI, U.S. Department of Energy

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

Approximately how many genes are in the human genome?

A

~30,000

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

What is the shortest human gene?

A

Histone (500 nucleotides)

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

What is the largest human gene?

A

Dystrophin (DMD) – 2,200 kb

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

Which chromosome has the highest number of genes?

A

Chromosome 1 (~2,968 genes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Which chromosome has the fewest genes?

A

Chromosome Y (~231 genes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Which chromosome is linked to various diseases?

A

Chromosome 17

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Name one major impact of the Human Genome Project. (3)

A
  • Blueprint of human DNA
  • Personalized medicine
  • Advances in genetics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Eukaryotic gene structure:
Binding site for RNA polymerase to initiate transcription

A

promoter region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Eukaryotic gene structure:
What sequence marks the 5’ end of mRNA?

A

Cap sequence (e.g., ACATTG)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Eukaryotic gene structure:
- Modified nucleotide __ is added after transcription.
- The sequences of this vary among genes but are necessary for mRNA binding to ribosomes and translation.

A
  • cap
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Eukaryotic gene structure:
What is the start codon for translation?

A

ATG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Eukaryotic gene structure:
The region between transcription and translation start sites.

A

Leader sequence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Eukaryotic gene structure:
What is the function of the Leader Sequence?

A

Determines the rate of translation initiation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Eukaryotic gene structure:
What are the coding sequences that form the final protein?

A

Exons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Eukaryotic gene structure:
What are the non-coding sequences between exons?

A

Introns

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Eukaryotic gene structure:
What happens to introns during RNA processing?

A

Removed during RNA splicing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Eukaryotic gene structure:
What sequence signals the end of translation?

A

TAA (in DNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Eukaryotic gene structure:
What is the 3’ Untranslated Region (3’ UTR)?

A

Transcribed but not translated.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Eukaryotic gene structure:
What sequence in the 3’ UTR signals poly(A) tail addition?

A

AATAA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Eukaryotic gene structure:
What is the function of the Poly(A) tail?

A

Enhances mRNA stability and translation efficiency.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Eukaryotic gene structure:
How long is the Poly(A) tail?

A

200–300 adenine residues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Expression of the Human β-Globin Gene:

On which chromosome is the β-globin (HBB) gene located?

A

Chromosome 11

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Expression of the Human β-Globin Gene:

What enzyme synthesizes pre-mRNA from DNA?

A

RNA polymerase II

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Expression of the Human β-Globin Gene:

What are the two modifications that enhance mRNA stability and translation? (2)

A
  • 5’ Capping
  • 3’ Polyadenylation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Expression of the Human β-Globin Gene:

Where does translation of β-globin occur?

A

Ribosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Expression of the Human β-Globin Gene:

What does the β-globin chain combine with to form hemoglobin?

A

α-globin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Expression of the Human β-Globin Gene:

What is the function of hemoglobin (HbA)?

A

Oxygen transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Levels of Gene Control:

Regulates which genes are transcribed.

A

Transcriptional Control

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Levels of Gene Control:

Selective RNA processing before translation.

A

Post-Transcriptional Control

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Levels of Gene Control:

What are the two key processes in Post-Transcriptional Control? (2)

A
  1. mRNA processing (intron removal)
  2. mRNA transport (nucleus to cytoplasm)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Levels of Gene Control:

What happens during Translational Control?

A

mRNA is translated into a protein.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Levels of Gene Control:

What is Post-Translational Modification?

A

Protein undergoes modifications (e.g., folding, phosphorylation) to become active.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Types of Regulatory Elements:

What are the two main types of regulatory elements? (2)

A
  1. Cis-Regulators
  2. Trans-Regulators
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Types of Regulatory Elements:

  • Specific DNA sequences that regulate genes on the same chromosome.
  • Control which genes are transcribed in specific cells.
A

Cis-Regulators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Types of Cis-Regulators:

  • Required for RNA polymerase binding and transcription initiation.
  • Upstream (~30 bp) from the transcription start site.
  • Specifies the time and place of transcription initiation.
A

Promoters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Types of Cis-Regulators:

  • Increase transcription efficiency and rate by binding transcription factors.
  • At the 5’ or 3’ ends of genes and in introns.
  • Activate promoters on the same chromosome.
A

Enhancers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Promoter Structure & Function:

What is the key sequence found in the promoter?

A

TATA sequence (TATA box or Goldberg-Hogness box)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Promoter Structure & Function:

Where is the TATA box located?

A

~30 base pairs upstream of the transcription start site.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Promoter Structure & Function:

Helps RNA polymerase bind and initiate transcription.

A

TATA sequence (TATA box or Goldberg-Hogness box)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Promoter Structure & Function:

How can the functional anatomy of promoters be analyzed?

A

By determining which bases are essential for efficient transcription.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Eukaryotic Transcription Initiation:

Why can’t RNA polymerase II bind directly to DNA?

A

It requires protein factors for proper transcription.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Eukaryotic Transcription Initiation:

What helps RNA polymerase II bind to the promoter?

A

Basal transcription factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Eukaryotic Transcription Initiation:

Binds to the TATA box and prevents nucleosome formation.

A

TFIID

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

Eukaryotic Transcription Initiation:

Recognizes and binds to the TATA box.

A

TBP (TATA-binding protein)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Eukaryotic Transcription Initiation:

Which transcription factor stabilizes TFIID?

A

TFIIA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Eukaryotic Transcription Initiation:

Helps RNA polymerase II attach to the complex.

A

TFIIB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Eukaryotic Transcription Initiation:

What additional factors help RNA polymerase II function? (3)

A
  • TFIIE
  • TFIIF
  • TFIIH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

Eukaryotic Transcription Initiation:

Unwinds DNA and releases RNA polymerase for transcription.

A

TFIIH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

Transcription:

  • Proteins that stabilize TBP and support transcription.
  • Prevent TBP from detaching from the TATA box.
A

TBP-associated factors (TAFs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Types of Cis-Regulators:

A DNA sequence that activates promoter usage, controlling transcription efficiency and rate.

A

Enhancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Types of Cis-Regulators:

What activates promoter usage?

A

Enhancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

Enhancer Structure & Function:

What do enhancers control?

A

Transcription efficiency and rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

Enhancer Structure & Function:

How do enhancers function?

A

Bind transcription factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

Enhancer Structure & Function:

What do enhancers regulate? (2)

A
  • Tissue-specific
  • temporal gene expression
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

Enhancer Structure & Function:

Where are enhancers located?

A

Far from promoters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

Enhancer Structure & Function:

What kind of genes do enhancers activate?

A

Cell-type specific genes

80
Q

Enhancer Structure & Function:

  1. What study examined pancreatic gene enhancers?
  2. What gene was used as a reporter in that study?
A
  1. Walker et al. (1983)
  2. CAT gene (chloramphenicol acetyltransferase)
81
Q

Enhancers - Walker et al. (1983):

Which cells activated the insulin enhancer?

A

Insulin-producing cells

82
Q

Enhancers - Walker et al. (1983):

Which cells activated the chymotrypsin enhancer?

A

Exocrine cells

83
Q

Enhancers - Walker et al. (1983):

What is the role of enhancers in cell specificity?

A

Turn on genes in specific cells

84
Q

Enhancers - Walker et al. (1983):

What type of enhancer inhibits transcription?

85
Q

What are the three (3) major domains of transcription factors?

A
  • DNA-binding domain
  • Trans-activation domain
  • Protein-protein interaction domain
86
Q

What binds to enhancers or promoters?

A

Transcription factors

87
Q

What are transcription factors classified by?

88
Q

Major domains of transcription factors:

What domain recognizes DNA sequences?

A

DNA-binding domain

89
Q

Major domains of transcription factors:

What domain regulates transcription?

A

Trans-activating domain

90
Q

Major domains of transcription factors:

What domain interacts with other proteins?

A

Protein-protein interaction domain

91
Q

DNA sequences that block transcription, restricting gene expression to specific cells or controlling timing.

92
Q

Silencers:
1. What gene is transcribed only after gut development in fetal mouse liver?
2. What cells initially do not transcribe the albumin gene?
3. What tissue signals liver formation?
4. What happens when the endodermal tube contacts heart-forming cells?

A
  1. Serum albumin
  2. Endodermal cells
  3. Cardiac mesoderm
  4. Silencer is released
93
Q

List the six (6) trans-regulatory factors (transcription factors that regulate gene expression by binding to DNA regulatory sequences (such as enhancers or promoters) to control transcription).

A
  1. Homeodomain Proteins
  2. Zinc Finger Standard
  3. Basic Helix-Loop Helix TF (bHLH)
  4. Basic Leucine Zipper (bZip)
  5. Nuclear Hormone Receptors
  6. Sox-2 TF
94
Q

Trans-Regulatory Factors:
- Function: Specify anterior-posterior body axes.
- Structure: 60 amino acids in a helix-turn-helix; the third helix binds the major groove, amino-terminal contacts the minor groove.
- Small amino acid changes alter DNA sequence recognition.

A

Homeodomain proteins

95
Q

What do homeodomain proteins specify?

A

Anterior-posterior body axes

96
Q

What structure do homeodomain proteins have?

A

Helix-turn-helix

97
Q

What binds the major groove in homeodomain proteins?

98
Q

What are the two (2) homeodomain proteins/homeodomain transcription factors?

A
  • Hox Transcription Factor
  • Pou (Pit-Oct-Unc) Transcription Factor
99
Q

Homeodomain proteins:
What do Hox TF mutations cause?

A

Homeosis - the transformation of one structure of the body into the homologous structure of another body segment.

100
Q

Homeodomain proteins: POU Transcription Factor:

What two (2) regions form the POU domain?

A

Homeodomain + second DNA-binding region

101
Q

Homeodomain proteins: POU Transcription Factor:

What pituitary-specific TF activates GH and prolactin?

A

Pit-1 (GHF1)

102
Q

Homeodomain proteins: POU Transcription Factor:

What ubiquitous TF binds an 8-bp octa-box sequence?

103
Q

Homeodomain proteins: POU Transcription Factor:

What B-cell-specific TF activates Ig genes?

104
Q

Homeodomain proteins: POU Transcription Factor:

What POU TF determines neuron fate in nematodes?

105
Q

Trans-Regulatory Factors:

Transcription factors that use zinc finger domains to bind DNA. The zinc ion stabilizes the structure.

A

Zinc Finger Standard

106
Q

Trans-Regulatory Factors: Zinc Finger Standard:

What stabilizes zinc fingers?

A

2 cysteines + 2 histidines

107
Q

Trans-Regulatory Factors: Zinc Finger Standard:

  1. What TF is critical for kidney and gonad development?
  2. What TF regulates hindbrain development?
A
  1. WT
  2. Krox 20
108
Q

Trans-Regulatory Factors:

  • Binds DNA via a basic amino acid region (10-13 residues).
  • Forms dimers with positive/negative regulators.
A

Basic Helix-Loop-Helix (bHLH) TFs

109
Q

Trans-Regulatory Factors: Basic Helix-Loop Helix (bHLH) TFs:

  1. What muscle-specific TF forms a complex with E12/E47?
  2. What differentiation inhibitor forms a complex with E12/E47?
110
Q

Trans-regulatory Factors:

  • Structure: α-helix with leucine residues, forms Leucine Zipper dimers.
  • These TFs contain a leucine zipper motif, which facilitates dimerization and DNA binding.
A

Basic Leucine Zipper (bZip) TFs

111
Q

Trans-regulatory Factors: Basic Leucine Zipper (bZip) TFs:

What bZip TF is involved in liver differentiation?

112
Q

Trans-Regulatory Factors:

  • Mediate hormone effects on genes.
  • Functions: Secondary sex determination & craniofacial development.
A

Nuclear Hormone Receptors

113
Q

Trans-Regulatory Factors: Nuclear Hormone Receptors

What do nuclear hormone receptors mediate?

A

Hormone effects on genes

114
Q

Trans-Regulatory Factors: Nuclear Hormone Receptors

What two (2) processes are controlled by nuclear hormone receptors?

A
  • Secondary sex determination
  • craniofacial development
115
Q

Trans-regulatory Factors:

  • Sry-Sox bends DNA from “I” to “L”.
  • Important in mammalian sex determination.
116
Q

Trans-regulatory Factors: Sox-2 TFs

What does Sry-Sox do to DNA?

A

Bends from “I” to “L”

117
Q

Trans-regulatory Factors: Sox-2 TFs

Give an example of a Sox TF. (3)

A
  • Sry
  • SoxD
  • Sox2
118
Q

What are the three (3) types of RNA Polymerase?

A
  • RNA Polymerase I
  • RNA Polymerase II
  • RNA Polymerase III
119
Q

What does RNA Polymerase I transcribe?

A

Large rRNAs

120
Q

What does RNA Polymerase II transcribe?

A

mRNA precursors

121
Q

What does RNA Polymerase III transcribe?

A

tRNA, small RNAs

122
Q

Transcription of a Gene:

What determines which genes are transcribed and expressed?

A

Cell differentiation

123
Q

Transcription of a Gene:

What is added to the 5′ end of pre-mRNA?

A

7-methyl-guanylate (Capping)

124
Q

Transcription of a Gene:

What is added to the 3′ end of pre-mRNA?

A

Poly-A tail (Polyadenylation)

125
Q

Transcription of a Gene:

Function of polyadenylation? (3)

A
  • mRNA stability
  • exit
  • translation
126
Q

Transcription of a Gene:

What removes introns from pre-mRNA?

127
Q

Transcription of a Gene:
Transcriptional Control
What allows one gene to produce different proteins?

A

Alternative splicing

128
Q

Transcriptional Control:

What regulates gene activity through chemical modifications?

A

Epigenetic mechanism

129
Q

Transcriptional Control:

What inactivates genes through chemical modification?

A

DNA methylation

130
Q

Transcriptional Control:

What modification allows transcription by unpacking DNA?

A

Histone acetylation

131
Q

DNA Methylation:

Where does DNA methylation occur to regulate genes?

A

Promoters (Cytosine residues)

132
Q

DNA Methylation:

Effect of promoter methylation?

A

Gene inactivation

133
Q

DNA Methylation:

What is the role of genomic imprinting?

A

Differentiates maternal/paternal genes

134
Q

DNA Methylation:

What ensures dosage compensation in females?

A

X-chromosome inactivation

135
Q

Histone Methylation:

What histone is methylated for gene silencing?

136
Q

Histone Methylation (H3-K9 Methylation):

What does histone methylation promote?

A

Chromatin repression

137
Q

Histone Methylation (H3-K9 Methylation):

Binds methylated H3-K9, silences genes

A

HP1 proteins

138
Q

Histone Methylation (H3-K9 Methylation):

What structure results from histone methylation?

A

Closed chromatin

139
Q

Mammalian X-Chromosome Dosage Compensation:

Why is X-chromosome dosage compensation needed?

A

Equal X-linked gene expression

140
Q

Mammalian X-Chromosome Dosage Compensation:

How do Drosophila achieve dosage compensation?

A

Increase male X transcription

141
Q

Mammalian X-Chromosome Dosage Compensation:

How do mammals achieve dosage compensation?

A

X-chromosome inactivation

142
Q

X-Chromosome Inactivation:

What type of chromatin does an inactivated X form?

A

Heterochromatin

143
Q

X-Chromosome Inactivation:

When does X-chromosome inactivation occur?

A

Implantation

144
Q

X-Chromosome Inactivation:

Is X-chromosome inactivation reversible?

145
Q

Effects of Mutant X Chromosome in Mice:

  1. What happens to ectodermal cells?
  2. What layer fails to form?
  3. When does embryonic death occur?
A
  1. Cell death
  2. Mesoderm
  3. By day 10
146
Q

Histone Acetylation & Deacetylation:

What happens when histones are acetylated?

A

Chromatin opens

147
Q

Histone Acetylation & Deacetylation:

What removes the positive charge of histones?

A

Acetylation

148
Q

Histone Acetylation & Deacetylation:

What condenses chromatin and silences genes?

A

Deacetylation

149
Q

Polyadenylation:

  1. What enzyme adds the poly-A tail?
  2. Approximate number of adenylate nucleotides added?
A
  1. Poly(A) polymerase
  2. 150-200
150
Q
  1. What domain initiates transcription?
  2. What is produced during transcription initiation?
A
  1. CTD (Carboxyl Terminal Domain)
  2. 5’-triphosphorylated transcript
151
Q

Key Transcription Proteins (3)

A
  1. TFs + TFs → TIC (Transcription Initiation Complex)
  2. TBP-AF – Coactivators
  3. Mediator Complex
152
Q

Key Transcription Proteins:

Formation of the transcription initiation complex with RNA Polymerase II.

A

TFs + TFs → TIC (Transcription Initiation Complex)

153
Q

Key Transcription Proteins:

TBP (TATA-binding protein) and its associated factors (TAFs) help recruit TFs and RNA Pol II.

A

TBP-AF – Coactivators

154
Q

Key Transcription Proteins:

Bridges activators with the transcription machinery for efficient transcription.

A

Mediator Complex

155
Q

Transcription Complex & Enhanceosome Complex:

What does HMG-1 (High Mobility Group 1) do?

A

DNA Bending

156
Q

Transcription Complex & Enhanceosome Complex:

What is the function of the enhanceosome complex?

A

Facilitates transcription regulation

157
Q

Transcriptional Control of Genes:

  1. What percentage of genes are typically repressed?
  2. What percentage of genes are expressed in a cell?
158
Q

Control Before Transcription:

What process amplifies genes for increased mRNA and ribosome production?

A

Selective gene amplification

159
Q

Control Before Transcription:

Where are lampbrush chromosomes found?

A

Amphibian oocytes

160
Q

Control Before Transcription:

What immune cells undergo gene rearrangement?

A

B- and T-lymphocytes

161
Q

Control Before Transcription:

What does gene rearrangement produce?

A

10 million immunoglobulins (Igs)

162
Q

Control After Transcription:

What chemical modification is involved in gene imprinting?

A

Methylation

163
Q

Control After Transcription:

What process leads to mosaic tissue effects (e.g., calico cats)?

A

X-chromosome inactivation

164
Q

Control After Transcription:

What effect does deacetylation have on chromatin?

A

Tightens chromatin, represses transcription

165
Q

Control After Transcription:

What stabilizes mRNA by adding ~200 adenyl groups?

A

Polyadenylation

166
Q

Levels of Gene Control:

What determines which transcripts are processed into mRNAs?

A

Censorship

167
Q

Levels of Gene Control:

What percentage of human genes undergo alternative splicing?

168
Q

Levels of Gene Control:

What is the example of alternative splicing in different tissues?

A

Tropomyosin (muscle vs. neuronal cells)

169
Q

Post-Transcriptional Gene Silencing (PTGS):

Another name for PTGS?

A

RNA interference (RNAi)

170
Q

Post-Transcriptional Gene Silencing (PTGS):

What happens to genes in PTGS?

A

Down-regulation at the RNA level

171
Q

Post-Transcriptional Gene Silencing (PTGS)

What is an example of transcriptional gene silencing (TGS)? (2)

A
  • Retroviral genes
  • transposons
172
Q

Alternative mRNA Splicing:

What complex removes introns during splicing?

A

Spliceosome

173
Q

Alternative mRNA Splicing:

What joins exons after intron removal? (2)

A

Splicing factors (SF) & snRNPs

174
Q

Alternative mRNA Splicing:

Why is alternative splicing important?

A

Increases protein diversity

175
Q

Alternative mRNA Splicing:

What human health issue is linked to splicing defects?

176
Q

Types of Alternative mRNA Splicing (5)

A
  1. Alternative 5’ Splicing
  2. Alternative 3’ Splicing
  3. Intron Retention
  4. Mutually Exclusive Exons
  5. Exon Skipping
177
Q

Types of Alternative Splicing:

What type of splicing includes/excludes a 5’ exon portion?

A

Alternative 5’ splicing

178
Q

Types of Alternative Splicing:

What gene’s splicing determines apoptosis regulation?

179
Q

Types of Alternative Splicing:

What type of splicing affects the 3’ exon?

A

Alternative 3’ splicing

180
Q

Types of Alternative Splicing:

What type of splicing keeps an intron in mRNA?

A

Intron retention

181
Q

Types of Alternative Splicing:

What type of splicing selects different exons for different mRNAs?

A

Mutually exclusive exons

182
Q

Types of Alternative Splicing:

What is an example of exon skipping?

A

FGFR2 gene

183
Q
  1. What is a hybrid between a zebra and a donkey?
  2. How does this hybrid foal compare to a zebra foal (size)?
A
  1. Zebroid
  2. Twice as large
184
Q

What determines mRNA stability?

A

Poly(A) tail length

185
Q

How does polyadenylation affect translation?

A

Increases stability & translation rates

186
Q

Which milk protein’s mRNA half-life increases due to prolactin? How much does this mRNA stability increase in lactation?

A
  • Casein
  • 28-fold
187
Q

What happens to stored oocyte mRNAs before fertilization?

188
Q

What activates stored mRNAs?

A

Ionic signals (fertilization/ovulation)

189
Q

What proteins control cell fate in Drosophila embryos? (2)

A

Bicoid & nanos

190
Q

What regulates mRNA translation through spatial control?

A

Cytoplasmic localization

191
Q

Which mRNA is transported to the vegetal pole in frog oocytes?

192
Q

Where does Vg1 mRNA remain after fertilization?

A

Vegetal blastomeres

193
Q

How does cell differentiation occur?

A

Selective gene expression

194
Q

At what levels is gene expression regulated?

A

Multiple levels (transcription to translation)

195
Q

What controls specific gene expression?

A

Transcription factors (TFs)

196
Q

How does gene regulation function?

A

As a network

197
Q

How do genes interact with protein synthesis?

A

Dynamic feedback system

Developmental Biology (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions