Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology-151 2025 > Exam 6: DNA-Trancription and Translation > Flashcards

Exam 6: DNA-Trancription and Translation Flashcards

1
Q

John Miescher

A

Isolated a substance called “nuclein” from fish sperm and pus.

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

Griffith

A

Transformation- seeking vaccine for a form of streptococcal pneumonia.

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

Avery

A

Discovered that DNA was the transforming substance but was largely ignored.

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

Hershey and Chase

A

Found that DNA was the hereditary substance using bacteriophage viruses.

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

Chargaff

A

%A=%T
%G=%C

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

Linus Pauling

A

Incorrect model of DNA

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

Franklin and Wilkins

A

Using X-ray crystallography, these two produced a photographic image of DNA that was vital to understanding the structure of DNA
-Franklin discovered its helical
-Wilkins discovered molecule had a diameter of 2nm and makes a full turn of the helix every 3.4 nm

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

Watson and Crick

A

Determined the structure of DNA
Built a model of a double helix using the cray and chemistry of DNA.

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

Meselsohn and Stahl

A

Experiments by these two support Watson and cricks semi conservative model of DNA replication using radioisotopes
Demonstrates that each new DNA molecules consists of one original and one newly synthesized strand.

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

Beadle and Tatum

A

Demonstrated that genes control specific chemical events, proposing the, “one gene, one enzyme” hypothesis, later refined to “one gene, one polypeptide”

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

Purines

A

Double rings

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

What are the two purines?

A

Adenine and guanine

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

Pyrimidines

A

Single ring

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

What are the two pyrimidines?

A

Thymine and cytosine

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

Where does replication occur?

A

Sites called origins of replication

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

What separates the 2 DNA strands ?

A

Helicase enzyme

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

What do DNA polymerase do?

A

Catalyze the elongation of DNA at a fork. It pairs complimentary nucleotide nitrogen bases to form daughter strands of DNA

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

Leading strand

A

5’ to 3’
It is copied quickly and continuously

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

Lagging Strand

A

Runs “upside down” to elongate the lagging strand. DNA polymerase must work in the direction away from the replication fork.
- DNA polymerase copies Okazaki fragments, sections spliced using DNA ligase enzymes.
-DNA polymerase leaves strand, reattaches, copies and then leaves

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

What are the proofreading enzymes that cut out mistakes?

A

Nucleases

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

What does DNA polymerase do after proofreading?

A

Corrects almost all errors in base pairing

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

Gene expression

A

The process by which DNA directs protein synthesis, includes two stages: transcription and translation.

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

Gene expression can be

A

Turned on and off

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

Gene

A

A unit of DNA that codes for the production of the specific polypeptide (protein)
Occurs in the chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Metabolic (enzyme) pathway
Linking genes to enzymes requires understand that cells synthesize and degrade molecules in a series of steps. Each gene dictates a the production of specific enzyme
26
What are the two stages of protein synthesis?
Transcription and translation.
27
Where does transcription occur?
In the nucleus
28
Transcription is the synthesis of what?
mRNA
29
Where does translation occur?
It occurs in the ribosome
30
Translation is the synthesis of what?
polypeptides
31
Structure of DNA
2 strands deoxyribose C - G A - T
32
Structure of RNA
1 strand ribose C - G A - U
33
Messenger RNA (mRNA)
carrier the DNA code to the ribosome, they copy and carry .
34
Transfer RNA (tRNA)
transports specific amino acids into position along the ribosome, according to the code in the mRNA
35
Ribosomal RNA (rRNA)
Along with protein, t=forms the ribosome and helps attract and attach to mRNA
36
How does DNA control cell activity?
By determining what kinds of proteins the cell can make. - Channel and carrier proteins determine what materials enter and exit the cell; glycoproteins and receptor proteins determine what substrates are attracted to the cell. - Many proteins are enzymes that determine all other chemical reactions in cells. - Many proteins from structure.
37
What is genetic code?
the nucleotide of DNA and RNA that carry genetic information in living cells. 4 nucleotide bases in DNA and 3 nucleotide bases for an amino acid (RNA)
38
What catalyzes transcription?
RNA polymerase.
39
Transcription Unit
The stretch of DNA that is transcribed.
40
Mutation
Any permanent change in DNA, spontaneous (mistakes during replication), or mutagens (mutation-generating agents)
41
What are some examples of cancer-causing agents?
chemicals and radiations
42
What are two types of frameshift mutations?
Addition and deletion
43
Addition mutation
Insertion of extra nucleotide nitrogen base (addition of 1) example: tay-sach
44
Deletion mutation
Leaving out nucleotide nitrogen base. example: cystic fibrosis
45
Inversion mutation
Region of DNA "flip-flops", it is common but no definite effect has been found yet in humans. (evolution of apes and humans) Example: split hands or feet
46
Point Mutation
Base substitution, one nucleotide nitrogen base is substituted for another. example: sickle cell and PKU
47
Silent mutation
Do not affect the amino acid a codon produces because of redundancy in the genetic code.
48
Translocation Mutation
One piece of DNA breaks off and is inserted in another. Example: cancer and down syndrome.
49
Repeated tantem mutation
Sequence is repeated Example: Huntington's disease
50
Mutations are the source of ...
new genes that may be harmful, neutral, or beneficial.
51
Example of beneficial mutation
AIDS resistance, because it lacks the CCR5 receptor virus needed to infect cells.
52
How many mutations does each human have?
60 (frequent)
53
Sources of mutations?
Spontaneous or mutagens
54
Operons
control gene expression in prokaryotes - it is the entire stretch of DNA that includes the operator, promoter, and the gene it controls.
55
The operon can be switched off by a...
protein repressor (inhibitor) produced by a regulator gene.
56
trp is a
repressible (being able to be controlled) operon
57
Lac-Operon
Usually off but is activated with the presence of lactose.
58
No lactose
repressor protein attaches to an operon gene and blocks RNA polymerase - OFF
59
Lactose present
Lactose binds to the repressor and cannot attach to the operator; RNA polymerase attaches to the promoter- ON
60
Chromosomes puff, lampbrush chromosomes
active and uncoiled
61
Barr bodies during mitosis
coiled and inactive
62
Methylation
added to nitrogen base, methylation is often permanent, and it causes DNA to coil tightly- turns it off
63
Acetylation
Attaches to the histone tail and it causes DNA to uncoil from histones. Deacetylation or methylation causes it to turn off genes.
64
Epigenetic Inheritance
The inheritance of traits transmitted by mechanisms not directly involving the nucleotide sequence Traits are influenced by environment or experiences that may impact gene expression.
65
Transcription Activator
A protein that binds to an enhancer and stimulates the transcription of a gene. Attaches to promoter and enhancers, attract RNA polymerase and begins transcription, depending on which RNA segments are treated as exons and which as introns.
66
Alternating RNA splicing
Different mRNA molecules are produced from the same primary transcript, depending on which RNA segment is treated as exons and which as introns.
67
Hormones
Steroidal enters nucleus, attach to promotor; and turns on or off gene.
68
Genes are affected through
signal transduction
69
Cellular differentiation
The process by which cells become specialized in structure and function. Different groups of genes are activated/inactivated in different cell types.
70
Cytoplasmic Determinants
Cytoplasmic determinants are maternal substances in the egg that influence early development. As the zygote divides in mitosis, cells contain different cytoplasmic determinants, which can lead to different gene expressions.
71
Inductive Signals
Signal molecules from embryonic cells cause transcriptional changes near target cells. Thus, the interaction between cells induces the differentiation of specialized cell types.
72
Homeobox
Major regulatory genes that master control for sequences of genes that control development
73
Why does normal hemoglobin mover further?
Because it is more negatively charged, due to glutamic acid.
74
Why does sickle cell anemia hemoglobin move much slower?
Val is less negatively charged
75
In the DNA isolation lab, why was meat tenderizer used?
it further dissociates the proteins that package DNA, releasing it into the solution.
76
In DNA isolation lab was cold 95% ethanol used?
Cold ethanol is used to precipitate (solidify and become visible) while preserving the hydrogen bonds (preventing strands from damaging)
77
In the DNA isolation lab, what was the reason for mixing cells with chloride and detergent to form the strawberry filtrate?
To break down membrane lipids and proteins inside the cells, releasing the DNA into the solution.

Biology-151 2025 (10 decks)

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