Brainscape's Knowledge GenomeTM

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


See full index

1 MTM > Lectures 1-5 > Flashcards

Lectures 1-5 Flashcards

1
Q

What gives proteins charge?

A

Projecting side-chains can offer charge

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

Why are polypeptide chains flexible?

A

The peptide bond is essentially planar

There is a 40% double bond character around C-N

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

Which tertiary structure is preferred?

A

That of the lowest energy

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

What tells a protein where to go?

A

Its’ own specific sorting signal

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

What catalyses phosphorylation of proteins?

A

Kinase (PKA)

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

What catalyses dephosphorylation of proteins

A

Phosphatatse

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

What are the stages to growth factor signalling?

A 
Activation of the tyrosine kinase receptor (dimerisation, phosphorylation)
Cytoplasmic signallling (adaptor protein binds to phosphorylated receptor, Ras (G-protein) binds to adaptor)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the importance of UPR?

A

operates as a homeostatic response.

keeping the cell folding capacity in balance with its needs (limiting ER stress, decreasing unfolded protein production)

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

What is ERAD?

A

Endoplasmic Reticulum associated protein degreadation

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

What genes dictate proliferative control?

A

Oncogenes and tumour suppressor genes

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

Why would the cell cycle use checkpoints? (2)

A

To regulate proliferation

To maintain genomic integrity

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

Where are the major checkpoints found?

A

Middle of G1
Between G1 and S
Between G2 and M

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

What growth factors are involved in the checkpoint at G1?

A

none lmao tricked you

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

What does the G1 restriction point check for? What might happen?

A

The point at which the cell does not need extracellular signals to then divide.

checks for cell size (big enough to divide) and nutrient availability for daughter cells

If not it slips into G0 (quiescence), which is the state of most cells in the body

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

What is checked in metaphase?

A

connections between chromosomes and mitotic cpindles by the kineticore

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

What are kinases activated by?

A

cyclin

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

How does cyclin initiate mitosis?

A

build by in interphase, eventually forming maturation promoting factor (M-Cdk), initiating mitosis by phosphorylation

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

What is pRB?

A

The retinoblastoma protein

TS protein, binding to transcription regulators for genes for cell proliferation at the restriction point

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

What would inhibit pRB function?

A

specific growth factors, which activate Cdk’s, phosphorylating pRB

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

What happens when a receptor becomes oncogenic?

What might have the same effect?

A

Constant efficacy, deregulating cell proliferation

A mutated continuously active Ras protein

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

What are the yields of glycolysis?

A

2 pyruvate
2 ATP
2 NADH

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

glycolysis: how is glucose primed?

How many carbons does the product have?

A

in 2 phosphorylation steps and one isomerisation step to form fructose-1,6-bisphosphate
(6)

23
Q

glycolysis: what is F-1,6-bp split into?

A

Glyceraldehyde 3-phosphate

eventually forms pyruvate (3C)

24
Q

Which steps in glycolysis are irreversible?

A 
hexokinase and phosphofructokinase (priming)
pyruvate kinase (splitting)
25
Q

anaerobic respiration: Why is lactate formed?

A

NAD+ must be regenerated to drive the glycolysis equilibrium forward and produce ATP

26
Q

anaerobic respiration: How is lactate produced?

A

pyruvate is converted to lactate using lactate dehyrdrogenase

27
Q

What causes Angina pectoris?

A

atherosclerosis blocks coronary arteries, reducing )2 supply to the heart, increasing lactate and hence leading to chest pains.

28
Q

What intermediate in anaerobic respiration in RBC’s decreases their affinity for O2?

A

2,3-biphosphoglycerate

29
Q

What happens in the Cori cycle?

A

Lactate from muscle tissue and alanine is converted to pyruvate, and then to glucose-6-phosphate in gluconeogenesis in the liver

30
Q

What is required to form one glucose molecule in gluconeogenesis?
What is the net loss?

A 
2 pyruvate
4ATP
2GTP
2NADH
net loss: 2ATP, 2GTP
31
Q

What is used to perform the Link’s reaction?

How many enzymes does it use?

A

Pyruvate dehydrogenase complex

3 enzymes

32
Q

What happens at E1 of the pyruvate dehydrogenase complex?

A

Pyruvate undergoes oxidative decrarboxylation, adding TPP

33
Q

What happens at E2 of the pyruvate dehydrogenase complex?

A

lipoamine transfers the acetyl group to CoA

34
Q

What happens at E3 of the pyruvate dehydrogenase complex?

A

regeneration of lipoamine

35
Q

What might remove some carbons from Acetyl CoA?

A

The formation of fatty acids

36
Q

What are the subunits of cholesterol?

A

polar head group
rigid planar steriod ring structure
non-polar hydrocarbon tail

37
Q

What does cholesterol do?

A

as 37 degrees it makes the membrane less fluid

This is because cholesterol is short and rigid, making membranes less permeable

38
Q

What are transmembrane domains of proteins called?

A

hydrophobic amino acids orgnised into alpha-helical structures
(hydrophobic side-chains aare on the outside)

39
Q

What are anchors?

A

integrins linking intracellular matrix to actin

40
Q

what classes of membrane proteins are involved in facilitated diffusion?

A

channels

uniporter carrier proteins (has a binding site)

41
Q

What comprises the net force driving charged solutes across the membranes?

A

concentration gradients
membrane voltage
(called the electrochemical gradient)

42
Q

How is the Na+ electrochemical gradient maintained?

A

Na+ and K+ active transport, 3Na+ out against the concentration gradient, 2 K+ in against the concentration gradients

43
Q

What is a coupled transporter?

A

one solute with the gradient, one solute against (antiport) (secondary AT)
CAN BE SYMPORT

44
Q

What are ATP driven pumps?

A

primary active transport, straight up, normal AT

45
Q

What does the Na+/glucose symporter do?

A

Na+ electrochemical gradient is used to drive the movement of glucose against its’ concentration gradient

46
Q

What does the Na+/Ca2+ antiporter do?

A

moves 1 Ca2+ out for 3 Na+ in (Ca2+ against the concentration gradient)

47
Q

What is the effect of the Na+/Ca2+ antiporter?

A

it reduces intracellular Ca2+ conc. reducing strength of cardiac muscle contraction

48
Q

What is checked in G2?

A

the status of DNA replication from S phase

49
Q

How does m-Cdk switch itself off?

A

initiating a process which leads to the destruction of cyclin.

50
Q

Which cdk’s and cyclins are active at the restriction point?

A

cdk4 / cyclin D

cdk2 / cyclin (A/E)

51
Q

which cdk’s and cyclins are active at the turn from G1 to S phase?

A

cdk 2 / cyclin (A/E)

cdk 1 / cyclin (A/B)

52
Q

Which cdk’s and cyclins are active at the turn from G2 to M phase?

A

cdk 1 / cyclin (A/B)

53
Q

What might inhibit a cdk?

A

INK and CIP inhibit cdk4

54
Q

How does p53 work?

A

activates the transcription of p21, which inhibits cdk’s preventing transition into S phase, giving time for DNA to repair or apoptosis i think

1 MTM (5 decks)

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