Brainscape's Knowledge GenomeTM

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


See full index

Block 1 > Molecular Biology week 1 > Flashcards

Molecular Biology week 1 Flashcards

1
Q

Semi conservative Replication

A

Replication that produces two copies that each contained one of the original parent strand and one new strand

Important because it maintains DNA integrity from generation to generation

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

DNA Polymerase

A

Catalyzes DNA synthesis

Elongation in 5’-3’ direction

Need a free 3’-OH

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

Replication Fork

A

site of the origin of replication

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

Okazaki Fragment

A

short newly synthesized fragments that are formed on the lagging strand during DNA replication

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

S-phase

A

Part of cell cycle where DNA replication takes place

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

DNA Primase

A

RNA polymerase that creates RNA primer

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

RNAse H

A

digests the RNA primer

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

DNA ligase

A

seals fragment

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

DNA Helicase

A

pries apart the double helix through the hydrolysis of ATP

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

Single Strand DNA binding protein (SSBP)

A

prevents single strands from forming “hairpins”

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

Sliding-clamp protein complex

A

holds the DNA polymerase on the DNA template

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

DNA topoisomerase

A

creates ds breaks to relieve supercoiling induced by DNA helicase and prevent DNA tangling during replication

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

What are the essential elements of DNA replication?

A

3’-OH, ATP, primer

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

DNA Polymerase target drugs

A

AZT for HIV

Acyclovir

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

DNA topoisomerase target drug

A

Irinotecan, Ciproflaxicin, Etoposide, Doxorubicin

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

Endogenous causes of DNA Damage

A

attack by reactive oxygen species

replication errors

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

Exogenous Causes of DNA Damage

A

UV and ionizing radiation including x-rays and gamma rays, plant toxins

man-made mutagenic chemicals that act as DNA intercalating agents, cancer chemotherapy and radiotherapy

Viruses

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

DNA Damaging Agent: x-rays, oxygen radicals, alkylating agents, spontaneous reactions

A

Results in: uracil, abasic site, gamma-oxoguanine, single strand breaks

Repaired via base excision repair

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

DNA Damaging Agent: UV light, polycyclic aromatic hydrocarbons

A

Results in: bulky adducts, pyrimidine dimer

Repaired via nucleotide excision repair

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

DNA damaging agent: IR, UV light, x-rays, anti-tumor agents, HU

A

Results in interstrand crosslink, double strand breaks

Repaired via Recombinatorial repair (HR/NHEJ)

21
Q

DNA damaging Agent: replication error

A

Results in: A-G, T-C mismatch, insertion, deletion

Repaired via mismatch repair (MMR)

22
Q

Depurination

A

When the glycosidic bond between the purine (A or G) and the sugar is hydrolytically cleaved and the purine base is removed. Can result in deletion mutation

23
Q

Deamination

A

Removal of an amine group.

In cytosine, the NH2 is hydrolytically cleaved thus forming Uracil which preferentially binds to adenine

24
Q

Base excision repair

A

cellular mechanism that repairs damaged DNA, it removes small, non-helix distorting base lesions (removes incorrect base)

ex. uracil DNA glycosylase

25
Q

Nucleotide excision repair

A

DNA repair mechanism that looks for bulky lesions (ex. pyrimidine dimers)

The portion of DNA is cut out by nuclease

26
Q

Nonhomologous End Joining (NHEJ)

A

DNA repair mechanism that trim broken DNA ends and ligate the trimmed ends together. Method to to repair ds DNA breaks

May result in mutation due to DNA loss

27
Q

Homologous end joining

A

DNA repair mechanism that uses sequence from the other identical c-some to fix error

28
Q

HNPCC

A

caused by defective DNA mismatch error

29
Q

Xeroderma pigmentosum

A

caused by defective nucleotide excision repair

30
Q

Ataxia-telangiextasia (AT)

A

caused by defective ATM gene which is responsible for multiple form of stress including ds breaks

Enzyme affected: ATM protein kinase

31
Q

BRCA-2

A

gene involved in homologous end joining, when defective, leads to increase risk of breast cancer

32
Q

Fanconi anemia

A

results from defective enzymes involved in DNA interstrand cross-link repair

33
Q

site specific recombination

A

the movement of specialized nucleotide sequences called transposons between non-homologous sites

34
Q

Genome

A

Genomes carry the information for all the RNA and protein that an organism will ever synthesize

35
Q

Viral genomes

A

some viral genomes are DNA, other are RNA

some are single stranded, others are double stranded

some integrate their genetic material into their host cell’s genome (HIV) others do not (Flu, Herpes)

Much smaller than human genome

no introns

36
Q

Bacterial Genomes

A

Prokaryotic genomes are dsDNA

Most have single c-some, either circular or linear

Smaller than human genome

No introns

37
Q

Human genome

A

A haploid cell contains 3 billion bps

Approx. 1.5% of genome encodes for proteins

~27k protein coding genes

Human are 99.9% identical at DNA level

38
Q

Human mitochondrial genome

A

circular duplex molecule of 16.5kb

encodes 13 proteins, 22tRNAs, and 2 rRNAs

Transcription and translation take place in mitochondria

39
Q

Purifying selection

A

selective removal of alleles that are deleterious

survival of the fittest

40
Q

Do the number of genes correlate with biological complexity

A

Yes, the more genes you have the more biologically complex the organism is

41
Q

Which of the following is more conserved: gene sequence or genomic structure?

A

gene sequence is more conserved than genomic structure

42
Q

Homologous genes

A

genes with similar sequence and function can be recognized across vast phylogenetic distances

43
Q

synteny

A

stretches of conserved gene order on chromosomes

44
Q

Mechanisms of creating ‘new’ genes

A

Intragenic mutation

Gene duplication - duplicated genes diverge independently

DNA segment shuffling - via recombination

Horizontal transfer - organism a and organism b shuffle genes around

45
Q

pseudogenes

A

genes that lose function or are irreversibly inactivated by mutation

46
Q

Single nucleotide polymorphisms (SNPs)

A

positions in a genome where some individuals have one nucleotide and others have a different nucleotide

47
Q

Simple sequence length polymorphisms

A

tandem repeat sequences that display length variations

48
Q

4Ps in P4 medicine

A

Predictive, Preventative, Personalized, Participatory

Block 1 (9 decks)

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