Brainscape's Knowledge GenomeTM

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


See full index

Biology > Molecular Genetics > Flashcards

Molecular Genetics Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What are the three main components of DNA?

A

Deoxyribose sugar, phosphate group, nitrogenous base.

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

What is a nucleotide ?

A

Molecules that consist of a five sugar with a hitrogenus base attached to their 5 carbon.

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

DNA has two strands of antiparallel nucleotides meaning?

A

The strands are running parallel but in opposite directions.

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

Complementary base parings are :

A

The pairing of the nitrogenous base of one strand of DNA with the nitrogenous base of another strand.

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

Adenine binds with…

A

Thymine

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

Guanine is bonded to …

A

Cytosine

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

The 5 end of a nucleotide is :

A

A phosphate group

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

The hydroxyl group of the deoxyribose is located at which end of the nucleotide.

A

The 3 end

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

What is the structure of DNA?

A

A double helix

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

The two strands of the DNA double helix are antiparallel, what does this mean ?

A

It means they are parallel to each other except in reversed order.

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

What are the 4 steps of DNA replication ?

A

DNA helicase, SSBS, DNA gyrase, and the replication fork.

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

What does DNA helicase do ?

A

The enzyme that unwinds the DNA. It does this by disturbing the hydrogen bonds.

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

SSBS does what ?

A

A protein that keeps the strands of DNA from re zipping ( continuously breaking hydrogen bonds

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

What does DNA gyrase do ?

A

T is the bacterial enzyme that relieves tension from the unwinding of the two strands

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

What is the replication fork ?

A

The region where the DNA replicating molecule is still bound to the single strand

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

What does DNA Polymerase 3 do?

A

It is the enzyme that is responsible for the building of the complementary strand.

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

What I the RNA Primer’s Job ?

A

Initiates DNA replication and is marked for removal as it is temporary.

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

Why does DNA polymerase 3 use to build the complementary strand ?

A

Free bases

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

What does the Leading strand do ?

A

The strand of DNA that is continuously synthesized during replication.

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

What is a lagging strand

A

A new strand of DNA that is synthesized in short fragments.

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

What are Okazaki fragments?

A

Short fragments of DNA

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

What does DNA polymerase 1 do ?

A

To remove the RNA primer and to replace it with the appropriate set of free bases

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

What does DNA ligase do ?

A

It is the enzyme that joins the DNA fragments together

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

What happens if DNA leaves the nucleus?

A

It gets damaged which renders it useless

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

How does DNA leave the nucleus without being damaged?

A

It is transcribed into a complementary RNA message.

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

How does RNA differ from DNA ?

A

Single stranded, is able to leave the nucleus, U base instead if T base.

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

What is RNA polymerase ?

A

Then enzyme that is responsible for the transcription of DNA into complementary mRNA

28
Q

What is mRNA?

A

Messenger RNA, responsible for the end product of a transcription gene, translated by ribosomes into protein.

29
Q

What is tRNA?

A

Transfer RNA, responsible for delivering amino acids to the ribosomes during the process of translation.

30
Q

What is rRNA?

A

Ribosomal RNA, binds with ribosome proteins to form ribosome.

31
Q

What is transcription ?

A

The process in which DNA is used as a template for the production of complementary messenger molecules.

32
Q

What are the three stages of transcription ?

A

Initiation, elongation and termination.

33
Q

What occurs during initiation of transcription ?

A

It starts when RNA polymerase binds to a segment of DNA that needs to be transcribed. The promoter is the segment that the RNA polymerase binds to. Once attached, the unwinding of the double helix begins.

34
Q

What occurs during elongation of transcription ?

A

The building of the single stranded mRNA occurs in the 5-3 direction. Anti parallel.

35
Q

What occurs during the termination of transcription?

A

mRNA is synthesized until the end of the gene has been reached, and RNA polymerase recognizes the termination sequence. mRNA dissociates from the DNA.

36
Q

What post transcriptional mods are required ?

A

A 5 cap, a poly A tail and spliceosomes.

37
Q

What is a poly A tail?

A

A 200-300 Strand of adenine free bases that are attached at the end of an mRNA transcript.

38
Q

What is a 5 cap?

A

A cap that is added to the head of the transcript to protect it from digestion after leaving the nucleus.

39
Q

What are spliceosomes?

A

What cuts out introns, this joining together extrons.

40
Q

What occurs during translation ?

A

Protein synthesis.

41
Q

What does tRNA do ?

A

It delivers the appropriate amino acids to the building sites.

42
Q

What happens during elongation of translation?

A

There must be a start codon. There are two sites for tRNA the A site and the P site ( acceptor and peptide)

43
Q

What does the acceptor site do ?

A

It is the place where the tRNA brings the amino acids.

44
Q

What does the Peptide site do ?

A

It is the site where the peptide bonds are formed between adjoining amino acids on a growing peptide chain.

45
Q

Describe the termination of protein synthesis.

A

Once the ribosome reaches a stop codon, the protein known as the release factor will aid the polypeptide in it’s release from the ribosome.

46
Q

Name the 4 control mechanisms of gene regulation.

A

Transcriptional, post transcriptional , translational, post translational

47
Q

What is an operon?

A

A cluster of genes under the control of one promoter and one operator.

48
Q

What I bacterial must split lactose to use it for growth ?

A

E. Coli

49
Q

B- galactosidase :

A

The enzyme that is responsible for the break down of lactose into its two monomers.

50
Q

It is inefficient for E.Coli to produce B Galactosidase when high levels of lactose are not present. what happens to prevent the production of B Galactosidase?

A

A negative control system called the Lac Operon blocks the production of B- Galactosidase.

51
Q

What is the Lac Operon ?

A

A cluster of genes under the control of one operator and one promoter, the genes collectively code for then enzyme and proteins that that are required for the bacterial cell to use lactose as a nutrient.

52
Q

What 3 genes are part of the lac operon ?

A

LAC A, LAC Z AND LAC Y

53
Q

What does Lac Z do ?

A

It codes for beta Galactosidase.

54
Q

What does Lac Y do ?

A

Codes for permease.

55
Q

What does Lac L do ?

A

It is a depressor protein tht binds to the operator, this preventing RNA polymerase from transcribing the lab operon genes.

56
Q

What is an inducer molecule?

A

A molecule that binds to the depressor proteins and causes a change in conformation this forcing the repressor molecule from falling off the operator.

57
Q

In short, what does the lac operon do ?

A

When lactos is not present, the Lac L protein binds to the operator covering part of the promoter and therefore blocking transcription.

58
Q

What is the Trp Operon?

A

A cluster of genes under the control of one promoter and one operator, the genes govern the synthesis of necessary enzyme when required to synthesize the amino acid tryptophan.

59
Q

How many genes make up the Trp operon ?

A

5 genes.

60
Q

What happens when there are high levels of Trp present?

A

The enzyme is repressed as the proteins bind to the repressor protein this changing it’s shape.

61
Q

Once levels decrease, what happens to the Trp operon ?

A

The repressor molecule falls off allowing the production of Trp to continue.

62
Q

What is a silent mutation ?

A

A single substitution of an amino acid that was codes for. Structurally and functionally the same.

63
Q

What is a missense mutation ?

A

A single substitution of an amino acid resulting in a poly peptide.

64
Q

What is a non sense mutation ?

A

A mutation that converts a codon for an amino acid to a stop codon.

65
Q

What is a frame shift mutation?

A

A mutation that causes the reading frame to change usually resulting in different codons, this is lethal.

66
Q

What is a point mutation ?

A

A mutation at a specific base pair in the genome.

Biology (6 decks)

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