Brainscape's Knowledge GenomeTM

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


See full index

Biology > Unit 5: DNA > Flashcards

Unit 5: DNA Flashcards

1
Q

Which scientists found how DNA is the genetic material of life? How did they prove it?

A

Hershey and Chase. They used bacteriophages to find whether DNA or proteins made up the genetic material

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

Macromolecules that make up DNA and RNA. Monomer that makes up the macromolecules

A

Nucleotides

Nucleic acids

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

3 parts of a nucleotide

A

Sugar, phosphate,nitrogenous base

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

Back bone of nucleotide

A

Sugar-phosphate

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

Nitrogenous bases of DNA and RNA

A

DNA: adenine, guanine, thymine, cytosine
RNA: adenine, guanine, cytosine, uracil

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

Purines and their structure

A

Adenine and guanine

Large, 2 rings

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

Pyrimidines and their structure

A

Thymine, cytosine, 1 ring

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

Main structural difference between RNA and DNA

A

RNA’s sugar is ribose
RNA has uracil instead of thymine
Ribose on RNA has an -OH group attached to a cytosine

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

Shape of DNA

A

Double helix. 2 strands of polynucleotides

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

Who discovered the structure of DNA?

A

Watson and Crick

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

How are 2 nucleotide strands of DNA held together?

A

Base pairing

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

Base pairing rules

A

A-T (or U for RNA)

C-G

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

Why is the model for DNA replication semi conservative?

A

Half of the parental molecule is maintained in each daughter strand

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

How do the 2 strands of DNA separate from each other?

A

They untwist

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

Where does DNA replication begin?

A

Origin of replication. Replication continues in both directions creating replication bubbles

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

Many origins of replication mean…

A

Replication can happen faster

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

Enzyme that adds new complementary nucleotides to each parent strand. Which end do they add them to?

A

DNA polymerase

Can only add to the 3’ end

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

What direction does the daughter strand grow?

A

Grows from 5’-3’ end

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

Function of DNA ligase

A

Links pieces of daughter strand together

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

Central dogma

A

Transcription and translation

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

Transcription

A

Transfer of genetic information from DNA to RNA

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

Translation

A

Transfer of information in RNA into a protein

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

Where do specific instructions for making proteins come from?

A

Genes. Between DNA and protein synthesis is RNA. DNA is transcribed into RNA, which is translated into a protein

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

Triplet code

A

Genetic instructions for an amino acid sequence of a polypeptide chain written in 3 base words, codons

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

Genetic code

A

Set of rules giving the correspondence between codons in RNA and amino acids in proteins

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

Where does transcription happen in eukaryotic cells?

A

The nucleus

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

RNA polymerase

A

RMA nucleotides are linked by transcription enzyme RNA polymerase
Unwinds DNA, elongates, and brings it back together

28
Q

Promoter

A

The start signal for a nucleotide sequence, marks where transcription begins. Specific binding site for RNA polymerase

29
Q

Initiation

A

Attachment of RNA polymerase to the promoter and start of RNA synthesis

30
Q

Elongation

A

RNA elongates. As RNA synthesis continues, RNA strand peels away from DNA template, which allows 2 separate strands of DNA to come back together in the already transcribed region

31
Q

Termination

A

RNA polymerase reaches sequence of bases innDNA template called a terminator. This signifies the end of the gene. Polymerase molecule detaches from RNA molecule and gene

32
Q

RNA that encodes amino acids

A

Messenger RNA. Messenger RNA is transcribed from DNA and that message is transcribed to polypeptides

33
Q

Where do transcription and translation occur in prokaryotic vs eukaryotic

A

Prokaryotic: in the cytoplasm
Eukaryotic: molecules required for translations exit nucleus via nuclear pores to enter the cytoplasm where machinery for polypeptide synthesis is located

34
Q

What must be added to mRNA before it can leave the nucleus?

A

Extra nucleotides, cap and tail
GTP cap on the 5’ end
Poly-A tail on the 3’ end

35
Q

RNA splicing

A

Cutting and pasting introns and extrons

36
Q

Transfer RNA

A

Used to convert codons or nucleic acids to amino acids for proteins

37
Q

How is translation initiated?

A
  1. An mRNA molecule binds to a ribosomal subunit. A special indicator tRNA binds to the specific codon called a start codon, where translation on mRNA molecule begins. Indicator tRNA carries the amino acid methionine to anticodon UAC to make AUG.
  2. Ribosomal subunit binds to a small one and tRNA fit into one of the 2 tRNA binding sites on the ribosome, the P site.
38
Q

Steps of translation: codon recognition

A

Anticodon of incoming tRNA molecule carries its amino acid and pairs with the mRNA codon in the A site of the ribosome

39
Q

Steps of transition: peptide bond formation

A

The polypeptide separates from the tRNA where it was bound (in the P site) and attaches by a peptide bond to the amino acid carried out by the tRNA in the A site. The ribosome catalyzes formation of the bond, one more amino acid is added to the chain.

40
Q

Steps of translation: translocation

A

The P site tRNA leaves the ribosome, which moves the tRNA in the A site to the P site. Codon and anticodon are still blinded and mRNA and tRNA move as a unit. Next mRNA codon is moved to the A site to be translated so the process can start again. Elongation continues until a stop codon reaches the ribosome’s A site

41
Q

Base substitution

A

Mutation where one base is changed to another

42
Q

Insertions and deletions

A

Series of nucleotides are changed

Alters the reading frame

43
Q

Mutagen

A

Physical or chemical agent that is the source of a mutation

44
Q

What are viruses made of?

A

A nucleic acid enclosed in a capsid, a protein coat

45
Q

What are the two life cycles of a virus?

A

Lytic cycle and lysogenic cycle

46
Q

Lytic cycle:

A

Reproductive cycle of phage T2. Host cell lyses and realizes the viruses produced within the cell

47
Q

Lysogenic cell

A

Viral DNA replication occurs without destroying the cell

48
Q

What is the genetic material of AIDS?

A

RNA. It has two identical copies instead of one

49
Q

How does HIV reproduce?

Why is called a retrovirus?

A

Reverse transcriptase. Catalyzes reverse transcription, the synthesis of DNA on an RNA template
It is a retrovirus because the flow of genetic information is RNA to DNA instead of DNA to RNA

50
Q

What type of cells does HIV affect?

A

Infects and eventually kills white blood cells

51
Q

Gene expression

The control of gene expression makes it possible for…

A

The flow of genetic information from genes to proteins, genotype to phenotype
Cells to produce specific kind of proteins when and where they are needed

52
Q

What is an operon?

A

Unit of genetic information that allows bacteria to regulate gene expression
Only exists in prokaryotes

53
Q

Lac operon

A

Used when there is lactose, all enzymes needed are created at once

54
Q

Repressor

A

Transcription is turned off

55
Q

Activator

A

Proteins turn operon son by binding to DNA

56
Q

Histones

A

Small proteins

57
Q

DNA packed rightly in structures in eukaryotic cells

58
Q

How does DNA packing help regulate gene expression?

A

Prevents gene expression by preventing transcription proteins from contracting the DNA

59
Q

tRNA stop codons

A

UAA, UAG, UGA

60
Q

Silent mutation

A

doesn’t change amino acid sequence

61
Q

missense mutation

A

1 nucleotide is changed, a different amino acid is created

62
Q

nonsense mutation

A

has an early stop codon

63
Q

framseshift muatation

A

caused by an insertion or deletion, causing a shift in the reading frame

64
Q

Bacteriophage

A

Virus that affects bacteria

65
Q

Why is the lysogenic cycle temperate?

A

It can switch between lytic and lysogenic cycles due to environmental stress

66
Q

Mouse experiment

A

Griffith
Had a bacteria with an S strain (disease causing) and R strain (non disease causing) with the R strain, the mice lived. With the S strain, they died. The S strain was heated and the mice lived. When the R strain was mixed with the heat killed S strain, the mice died

67
Q

Hershey and Chase

A

When they tracked DNA

Biology (12 decks)

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