Brainscape's Knowledge GenomeTM

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


See full index

Biochem (Midterm) > Enzymes and Isoenzymes > Flashcards

Enzymes and Isoenzymes Flashcards

1
Q

what do catalysts do?

A

increase the speed of chemical reactions

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

What do enzymes do in a reaction?

A

lower the energy of activation

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

Why are redox reactions so important to body function

A

Redox reactions are how we get our energy, phosphorylation of ADP to ATP in e transport chain where energy is released from the transfer of electrons

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

What is one of the major roles of the kidneys?

A

maintaining pH of the blood by getting rid of H and retaining bicarb when pH gets too low (acidotic) and retaining H and getting rid of bicarb when pH is too high (alkalosis)

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

What are the 2 characteristics of diabetic ketoacidosis?

A

low blood pH and high blood glucose in people with uncontrolled diabetes

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

What causes diabetic ketacidosis?

A

The lack of insulin doesnt allow glucose to be taken into the cell to be used for energy so cells switch to beta oxidation of fatty acids which makes ketone bodies. When some of these ketone bodies dissociate, they give off H+ which lowers the pH of the blood.

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

What are the signs of DKA?

A

vomitting, confusion, dehydration, coma

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

Rx for DKA?

A

insulin and fluids

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

What is LeChatelier’s principle?

A

Law of mass action: increasing the concentration of the reactants decreases the concentration of the products

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

what does a negative delta g value indicate?

A

the reaction will move forward on its own

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

What does a catalyst do?

A

increase the velocity at which a reaction will go forward by lowering the energy of activation

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

delta G =?

A

-RTlnKeq

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

What are the 2 types of biochemical reactions?

A

oxidation/reduction (OIL RIG)
acid base reaction (weak acid dissociates in H2O to release H+ and its conjugate base where a weak base combines with water to release its conjugate acid.

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

What is respiratory acidosis?

A

hypoventilation leads to increase in CO2 and leads to high H+ [ ]

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

what converts h2co3 into co2 and h2o in RBC?

A

carbonic anhydrase

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

what is the normal pH of blood?

A

7.37-7.43

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

What is metabolic acidosis?

A

caused by the addition of strong acids (ketone bodies or lactic acid) or the loss of basic elements like bicarb in diarrhea

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

What is respiratory alkalosis?

A

Hyperventilation leads to decreased CO2 levels and low H+ so higher pH

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

What is metabolic alkalosis?

A

addition of basic substances into the body like antacid or the loss of acid through vomiting

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

Where does the gastric proton pump live?

A

(H+/K+ ATPase) parietal cells lining the gastric lumen

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

What does the gastric proton pump do?

A

pumps protons into the gastric lumen where they combine with Cl- to make HCl

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

Why is the formation of HCl important in digestion?

A

it is a major component of gastric acid used to break down chyme

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

When would we want to tone down the gastric proton pump?

A

when patient has an ulcer, indigestion, heartburn

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

inhibiting the gastric prton pump could cause what?

A

hypochlorhydria which could cause failure to take in nutrients like B and Ca++, cause other digestive components to lose their efficiency (pepsin, gastric amalyse, gstric lipase)

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

What 3 molecules make up the catalytic triad used to make serine proteases (trypsin/chymotrypsin)?

A

Serine, histadine, asparagene

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

Which subunit is converted into a potent nucleophile in the cat. triad?

A

serine

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

what does the serine OH group do along with the N from hist in serine protease system?

A

cleavage of peptide bonds

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

what does the asp H bonds with histadine do in the serine protease system?

A

catalyzes the breaking of the peptide bonds by the N-OH from the catalytic triad

29
Q

What deprotonates the Ser-OH in serine protease system and why is that impotant?

A

H bonding of Asp-COOH and His-H allows His-N to do this. it is importnat because deprotonated Ser-OH initiated nucleophilic attack of carbonyl carbon on peptide

30
Q

What is an apoenzyme?

A

enyme without its cofactor

31
Q

What is a haloenzyme?

A

enz+ cofactor

32
Q

Metals as cofactors

A

stabelize structure and charge contribute to chemical reactivity

33
Q

When coenzymes are bound tightly they are called

A

prosthetic groups

34
Q

What causes Scurvy?

A

Lack of vitamin C

35
Q

Why is vitamin C important to collagen assembly?

A

it is a coenzyme for lysyl hydroxolase which is needed for collage assembly

36
Q

What is ariboflavinosis?

A

riboflaven is required for FAD synthesis and glutathione reductase needs FAD to to activate glutathione (VIP antioxidant). So, no riboflaven, no FAD, not functional glutathione and thus more ROS.

37
Q

What is ZN role in the metabolism of alcohol?

A

Zn is a cofactor for NAD+ and NAD+ is reduced to NADH when ethanol is converted to acetalaldehyde

38
Q

What are the 6 major classes of enzymes?

A

oxidoreductases, hydrolases, lyases, ligases, isomerases and transferases

39
Q

What is allopurinol know as?

A

treatment for gout but also a suicide inhibitor/inactivator

40
Q

How does allopurinol work?

A

It binds to xanthine oxidase which converts xhantine and hypoxanthine to uric acid (which causes gout at too high [ ] )

41
Q

Why is allopurinol a suicide inhibitor/inactivator?

A

because when it binds to xanthine oxidase, it converts to its active metabolite alloxanthine and is only slowly released.

42
Q

What is myasthenia gravis?

A

autoimmune disease where acetylcholine is blocked/ inhibited by ACh nicotinic R from binding to their ligand

43
Q

What are the S/S for M.G.?

A

muscle weakness, fatigue, inability to hold gaze

44
Q

Rx for MG?

A

any of the “stigmines” which work to bind to the active site of acetylcholine esterase and slowly releases to keep Ach in cleft longer

45
Q

What are metalloenzymes?

A

enzymes that require metals like Zn or Mg needed for enzymatic activity to occur

46
Q

How to inhibit metalloenzymes

A

chelating agents that bind and remove the metals from their enzyme. Ex: EDTA

47
Q

What agent is required for the biosynthesis of heme that can be inhibited by lead?

A

ALA

48
Q

What is the chelator for lead poisoning?

A

Ca-EDTAwith dimercaprol because lead has a higher affinity for EDTA than Ca so it displaces the Ca and created Pb-EDTA which can be peed out.

49
Q

S/S of lead poisoning

A

abdominal pain, irritability, headaches, impaired nervous system dev, and encephalopathy and sidroblastic anemia

50
Q

What are enzymes?

A

highly effective catalysts

51
Q

What is the Km value?

A

records affinity. it is the substrate concentration at which 50% of the active sites are full

52
Q

what is the Vmax?

A

max. velocity where all the enzyme is saturated with substrate

53
Q

what is competitive inhibition?

A

when the inhibitor binds to the active site on the enzyme instead of the substrate
doesnt change Vmax
increases the Km
because add enough substrate will reach vmax

54
Q

what is uncompetetive inhibition?

A

where the enzyme and substrate are allowed to bind but the inhibitor renders the complex inactive
decreases Vmax and Km by same factor because it allows them to bind but reners to complex inactive

55
Q

what is noncompetetive inhibition?

A

when the inhibitor binds to free and substrate bound enzyme at a new site
Vmax is lower but Kn is unchanged because you are taking enzyme out of the pool

56
Q

reversible ihibition is

A

when an inhibitor binds to an enzyme with noncovaelent interaction like H bonds

57
Q

irreversible inhibition

A

when an inhibitor binds to enzyme covaelently and cannot therefore be removed
decreases Vmax
no change to Km

58
Q

Wat is troponin?

A

a protein complex that is necessary for muscle contraction to occur.

59
Q

What is troponin complex made of?

A

tropomyosin binding site, the Ca+ binding site, and the inhibitor binding site

60
Q

What does Ca++ do to the troponin complex?

A

Ca binds to the Ca subunit which changes conformation allowing myosin to bind to actin filaments causing muscle contraction

61
Q

What role does troponin complex play in MI?

A

the inhibitory subunit is seen in elevated levels in serum after MI

62
Q

How can we use enzymes to diagnose?

A

When enzymes are seen in a particular tissue usually and they show up in blood, could indicate a disease process

63
Q

When alkaline phosphatase is seen in the blood?

A

bone disease

64
Q

sorbitol dehydrogenase and lactate dehydrogenase are seen in the blood when?

A

obstrutive liver disease

65
Q

Prostatic cancer is indicated by?

A

acid phosphatase in the blood

66
Q

Aldolase and aspartate aminotransferase seen in the blood when?

A

muscular dystrophhy is present

67
Q

when liver disorder is present what is seen in the blood?

A

alanine aminotransferase (ALT) and creatine kinase isoform

68
Q

What are isozymes?

A

enzymes that resemble eachother and react with the same substrate

69
Q

Allosteric inhibition

A

when downstream products either activate or inhibit upstream products

Biochem (Midterm) (11 decks)

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