Brainscape's Knowledge GenomeTM

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


See full index

COB Cumulative Final > Molecular Bio > Flashcards

Molecular Bio Flashcards

1
Q

What are the requirements of a chromosome?

A

Origin of Replication, telomere, centromere

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

DNA is basepairing is antiparallel because each strand’s sequence is complementary to partner. True or false?

A

true

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

Digestion with ___ break down DNA by cutting between nucleosomes and degrading the exposed DNA between nucleosome core particles (linker DNA)

A

nucleases

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

Each individual nucleosome core particle consists of __ histone proteins

A

8

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

Define pseudogenes

A

duplicated gene that has become irreversibly inactivated by multiple mutations

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

Describe what happens in gene duplication and divergence

A

both copies remain functional while diverging in sequence and pattern of expression

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

Name this DNA-binding motif:
simplest; two alpha helices connected by short chain of amino acids that make the turn at a fixed angle; longer helix portion = recognition module

A

helix-turn-helix

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

Name this DNA binding motif:

includes Zn atom; amino acid sequence drawn out looks like finger; binds to major groove

A

zinc finger domain

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

Name this DNA binding motif:
two alpha helical DNA binding domain; dimerizes through leucine zipper region; interactions between hydrophobic amino acid side chains at every 7 amino acids down one side of alpha helix: forms zipper structure; grabs DNA like clothespin

A

leucine zipper motif

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

Name this DNA binding motif:
consists of a short alpha chain connected by a loop to a second larger alpha chain; can occur as homodimers or heterodimers; three domains: DNA binding domain, dimerization domain, activation domain

A

helix-loop-helix

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

Describe regulation by RNA stability (2 things)

A

1 - decapping: exposed mRNA degraded from 5’ end

2 - mRNA degraded from 3’ end through poly-A tail and into coding region

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

____ ___ modifications are required by proteins to be functional

A

post translational

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

An apparatus that deliberately destroys aberrant protein is called what?

A

proteasome

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

In regards to specificity of protein degradation, there is one E1 ubiquitin activating enzyme and 1 proteasome but 30 E2 ubiquitin conjugating enzymes and hundreds of E3 accessory proteins. True or false?

A

true

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

Explain methylation and genomic imprinting

A

what genes get expressed (or not) from mom and dad

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

X-chromosome inactivation

A

even things out XX vs. XY - 2 X chromosomes vs 1 X chromosome

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

What are the 3 major transition checkpoints of the cell cycle

A

start: G1 to S
G2 to M
In M phase: anaphase and cytokinesis

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

True or false? activites of Cdks rise and fall during the cell cycle

A

true

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

Cdks are dependent on what proteins

A

cyclins

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

Without cyclin bound (inactive state) the active site of Cdk is blocked by a region of the protein called the __ ___

A

T loop

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

Phosphorylation of Cdk at T-loop fully activates enzyme. T or F?

A

true

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

What phosphorylates Cdk?

A

CAK

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

Name the effects of Wee1 and Cdc25 on Cdk-cyclin activities

A

Wee1: inactivates Cdk-cyclin by phosphorylation

Cdc25: removes phosphorylation, thus activating Cdk-cyclin

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

The 2 step process of chromosome condensation and resolution is brought about by what?

A

condensin

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

M-Cdk activates ____ to complete mitosis

A

APC/C

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

Chromosomes are attached to microtubules at the ____

A

kinetochore

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

Name the three forces that move chromosomes to opposite pole

A

1: depolymerization: major force pulls the kinetochore and chromosome toward the spindle pole. depolymerization of the plus end of the microtubule drives the pulling of the kinetochore poleward
2. microtubule flux: microtubules are moved toward spindle poles while being dismantled at minus end. tubular added at plus end while being removed at minus end
3. polar ejection force: kinesin-4, 10 motors on chromosomes interact with microtubules and transport chromosome from poles. results in push-pull phenomenon

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

Describe the intrinsic pathway of apoptosis

A

when cytochrome c is released from mitochondria, it binds to a protein called Apaf1 and forms apoptosome

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

What is the role of BH123 in apoptosis?

A

BH 123 proteins become activated, form aggregation in mitochondrial outer membrane and induce release of cytochrome c - then apoptosome formed

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

Bcl2 proteins regulate intrinsic apoptosis. true or false?

A

true

note: Bcl2 is an anti-apoptotic protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the role of BH3-only protein in apoptosis?

A

apoptotic stimulus

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

LAPs block caspases. true or false?

A

true

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

Anti-IAPs neutralize the IAPs and liberate what?

A

the caspases; leads to apoptosis

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

In regards to cancer genes, ___ involves single mutation event and activation of gene causing proliferation (dominant)

A

oncogenes

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

Describe tumor supressor genes and how they affect cancer

A

loss of function mutation. recessive - both alleles must be mutated

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

Heriditary form of Rb

A

loss of function or deletion of ONE copy of Rb in every cell- because defect is inherited

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

Sporadic form of Rb

A

since there are two normal alleles to begin with, need two sporadic mutations to occur

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

Describe the Apc mutation and how it can cause cancer

A

loss of function - Apc is a tumor suppressor gene

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

Gated Ion channels are common in ___ tissue

A

nervous

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

GPCRs use ___ transmembrane proteins

A

7-pass

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

Receptor tyrosine kinases are enzyme coupled. true or false?

A

true

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

Describe how a receptor tyrosine kinase receptor works

A
  1. RTK binds to SH2 of Grb2
  2. Grb2 also has SH3 domain
  3. SH3 of Grb2 binds to pralines of SOS which then binds to Ras
  4. Ras binds Raf and then rapid activation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

___ subunits are compact and globular and are flexible structures 5-9 nm in diameter

A

actin

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

In treadmilling, the plus end remains in __ formation and the minus end adopts ___ formation

A

T;D

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

Nucleotide hydrolysis leads to ____

A

treadmilling

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

Treadmilling predominates in ___ filaments

A

actin

47
Q

The following characteristics describe what:

long hollow cylinder; are made of tubulin, outer diameter 25nm, have one end attached to centrosome

A

microtubule

48
Q

If nucleotide hydrolysis proceeds more rapidly than subunit addition, the cap is lost and the microtubule begins to shrink. This is called what?

A

catastrophe

49
Q

GTP-containing subunits may still add to the shrinking end, and if enough add to form a cap, then microtubule growth resumes. This is called what?

A

rescue

50
Q

dynamic instability predominates in ____

A

microtubules

51
Q

the following characteristics describe what:

rope-like fiber; 10 nm diameter; help with mechanical strength

A

intermediate filaments

52
Q

Describe the construction of intermediate filaments

A

alpha helical in monomer; coiled-coil dimer; staggered tetramer of two coil-coiled dimers

53
Q

True or false? in intermediate filaments, there is no nucleotide binding site and structural polarity

A

true

54
Q

Keratins impart mechanical strength by anchoring intermediate filaments at site of cell-cell contacts called ____ and cell-matrix contacts called _____

A

desmosomes; hemidesmosomes

55
Q

In regards to accessory proteins for actin filaments, what does the ARP complex do?

A

nucleates assembly to form a web and remains associated with minus end

56
Q

In regards to accessory proteins for actin filaments, what does cofilin do?

A

binds ADP-actin filaments, accelerates disassembly

57
Q

In regardss to accessory proteins for microtubules, what does gamma-TuRC do?

A

nucleates assembly and remains associated with the minus end

58
Q 
Rac/Cdc42 = \_\_\_ actin
Rho = \_\_\_ actin
A

dynamic; rigid

59
Q

Rac activation promotes polymerization at the cell periphery leading to the formation of ___ extensions

A

lamellipodia

60
Q

Cdc42 activation triggers actin polymerization and bundling to form ____

A

filopodia

61
Q

Rho activation promotes both the bundling of actin filaments with ___ __ filaments into stress fibers and the clustering of interns and associated proteins to form focal contacts

A

myosin II

62
Q

Name the junction:

seals gap between epithelial cells

A

tight

63
Q

Name the junction:

connects actin filament bundle in one cell with that in the next cell

A

adherens

64
Q

Name the junction:

connects intermediate filaments in one cell to those in the next cell

A

desmosomes

65
Q

Name the junction:

allows the passage of small water-soluble molecules from cell to cell

A

gap

66
Q

Name the junction:

anchors intermediate filaments in a cell to extracellular matrix

A

hemidesmosome

67
Q

In regards to adhesion proteins, ___ mediate cell-cell connection and ____ mediate attachment of cells to matrix

A

cadherin; integrin

68
Q

Adherents junctions often form a continuous ___ ___ close beneath the apical face of the epithelium, encircling each of the interacting cells in the sheet

A

adhesion belt

69
Q

Each sealing strand of tight junction is composed of a long row of ___ pass transmembrane adhesion proteins embedded in each of the two interacting plasma membranes

A

4

70
Q

two main tight junction proteins are what?

A

claudin and occludin

71
Q

Gap junction is spanned by channel forming protein called what?

A

connexin

note: 6 connexin protein subunits

72
Q

Gap junctions couple cells both electrically and metabolically. True or false?

A

true

73
Q

Intracellular linkage of integrin to actin is mediated by ___

A

talin

74
Q

What are FAK molecules and what do they do?

A

cytoplasmic protein tyrosine kinase; they autophosphorylate each other and make docking sites for Src-family kinases

75
Q

Describe the structure of a proteoglycan

A

long polysaccharide/core complex linked to extensive hyaluronic acid chain

76
Q

describe the triple helix of collagen

A

each chain twists to left; twist helically around each other to the right

77
Q

Procollagen triple helix is formed where?

A

ER/Golgi Complex

78
Q

Procollagen is then cleaved outside of cell where it self-assembles into a what?

A

collagen fibril

aggregation of fibrils forms fiber

79
Q

What is the defective enzyme in scurvy?

A

prolyl hydroxylase

80
Q

What is the defective enzyme in ehlers-Danlos VI?

A

lysl hydroxylase

81
Q

What is the purpose of doing an SDS-PAGE?

A

separating proteins by size

82
Q

Why would you do Mass Spec?

A

identify unknown proteins

83
Q

Why would you do a western blot?

A

to analyze specific proteins

84
Q

Which ELISA is necessary for HIV test?

A

indirect

85
Q

What is an example of a sandwich ELISA?

A

pregnancy test

86
Q

Why would you use nuclear magnetic resonance?

A

to analyze protein structure

87
Q

Plasmids are cloning vectors. true or false?

A

true

88
Q

How do cDNA clones work?

A

DNA copy of mRNA; use reverse transcriptase

89
Q

What is pcr used for?

A

to detect altered genes or foreign DNA

90
Q

What does CSI utilize?

A

STRs

91
Q

True or false? mitochondria are more dynamic in high energy cells

A

false, less dynamic. become more fixed in high energy cells where they are packed tightly between myofibrils

92
Q

Do mitochondria retain their own DNA?

A

yes

93
Q

Mitochondria transfer RNAs are highly variable. changes in mt tRNAs have been linked to over 200 disease states. true or false?

A

true

94
Q

Accumulation of ___ generated by the respiratory chain can cause mito DNA damage

A

ROS

note: ROS increase with age, and the brain is particularly susceptible

95
Q

list the layers of the epidermis

A

granular, prickle, basal, basal lamina

96
Q

Olfactory receptors are what type of receptor?

A

G protein coupled receptor

97
Q

Describe the flow of action potential from olfactory receptor

A

relayed via axon to brain to glomeruli

98
Q

Where are glomeruli found?

A

olfactory bulbs

99
Q

Define totipotency

A

ability of a cell to give rise to all cells of an organism, including embryonic and extra embryonic tissues ex: zygote

100
Q

Define pluriptoency

A

ability of a cell to give rise to all cells of the embryo and subsequently adult tissues ex: embryonic stem cells

101
Q

define multipotency

A

ability of a cell to give rise to different cell types of a given lineage ex: adult stem cells

102
Q

true or false? founder stem-cell populations stay small; transit amplifying divisions let them generate and renew a big adult structure

A

true

103
Q

Explain the immortal strand hypothesis

A

to combat passing on mutation, stem cells divide asymmetrically, passing down a template parental strand

104
Q

How are ES cells derived?

A

what for zygote to become blastocyst and then take inner cell mass and culture on plate

105
Q

True or false? Adult stem cells are tissue specific

A

true

106
Q

give the function of the following types of RNAs:

tRNA; snRNA; snoRNA; miRNA; siRNA

A

tRNA: adaptor between mRNA and AAs

snRNA: splicing of pre-mRNA

snoRNA: chemically modify rRNAs

miRNA: regulate gene expression - block translation of specific mRNAs

siRNA: turn off gene expression

107
Q

Explain eukaryotic transcription initiation

A

TFIID binds to TATA box; recruitment of other TFs; formation of transcription initiation complex; Phosphorylation of CTD by TFIIH = elongation

108
Q

The genetic code is degenerate. True or false?

A

True

109
Q

What is the anticodon loop on a tRNA molecule?

A

a set of 3 consecutive nucleotides that pair with a complementary codon in an mRNA molecule

110
Q

What is the 3’CCA terminal region of a tRNA molecule?

A

the region which binds the AA that matches the corresponding codon

111
Q

Some tRNAs require accurate base-pairing only at the first two positions of the codon and can tolerate a mismatch at the third (wobble) position. This wobble base pairing explains why…..

A

so many of the alternative codons for an AA differ only in their third nucleotide

112
Q

UAA, UAG and UGA are what type of codons

A

stop codons

113
Q

Protein transfer/transport to various compartments is guided by ___ signals. Signal ___ remove signal after protein reaches final destination

A

sorting; peptidases

114
Q

Nuclear transport is ___, ___, and ____

A

bidirectional, selective, and gated

COB Cumulative Final (2 decks)

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