asd Flashcards Preview

MCM > asd > Flashcards

Flashcards in asd Deck (67):
1

Catabolism (break down) occurs via

oxidation

2

Anabolism (build up) occurs via

reduction

3

Oxidation

Gain oxygen
Lose H and electrons

4

Reduction

lose oxygen
Gain H and electrons

5

What are the standard conditions of delta G

pH=7
1 mole concentration of products and reactants
298 K

6

When K>1, the reaction is proceeding to the _____

right

7

ATP--> ADP + Pi produces how much NRG

-7.3 kcal/mol

8

ATP--> AMP+ PPi produces how much NRG

-10.9

9

PPi --> Pi and P produces how mich NRG

-4

10

What molecule carries the same amount of NRG as when ATP is hydrolyzed to form ADP+ Pi?

-7.3 kcal/mol.

Thioester. -7.3 kcal of NRG is stored in-between the [thiol group of co-A] and carboxyllic acid.

11

How can we alter Keq?

Principle of mass reaction and coupling

12

According to Le Chateliers principle, altering the amount of products and reactants will affect what?

Kinetcs

13

The first 3 steps of glycolysis are ______ & __________

coupled
irreversible

14

Addition/elimination rxn

Atoms are added or removed to multiple bonds

15

Substitution

1 FG is replaced with another

16

Rearrangement rxn

FG are rearranged

17

Oxidation and reduction

electrons are transferred from 1 molecule to another

18

What helps to maintain our pH?

acetic acid
bicarb

19

pka

strength of a acid

20

When is the buffering capacity of acid and bases perfect?

When pH=pKA.

21

How do kidneys regulate our blood pH?

Excrete H+ ions and reabsorb HCO3-.

22

What determines acid/base balance?

H+ (CO2) and HCO3-

23

increase blood pH. What will happen?

decrease excretion of H and bicarb

24

In respiratory acidosis, the eqn shifts to

LEFT

25

Metabolic acidosis occurs when

1. add a strong acid (lactate and ketone bodies).
2. Lose HCO3-

26

How can we lose HCO3- to cause metabolic acidosis?

Diarrhea and weakened kidney function

27

Metabolic alkalosis occurs when

1. take a strong base (antiacid)
2. Lose acid via vomiting

28

When we vomit, what happens to our pH?

pH will increase because we are throwing up an acid.
Metabolic alkalosis

29

Reducing agent

a substance that is responsible for the reduction that occurs by being oxidized

30

Oxidizing agent

Brings about an oxidation by being reduced.

31

Are co-factors and co-enzymes proteins?

No. They are not proteins.

32

Are co-factors and co-enzymes organic/inorganic?

Co-enzymes- organic and vitamins
Co-factors- inorganic

33

Co-factors

Metal ions or trace elements that interact with the enzyme using NON-COVALENT interactions

34

Co-factors interact with enzymes via ________ interactions

NON-COVALENT

35

Give examples of co-factors

Mg2+
Se
Cu
Zn
Fe

36

Mg2+ is a cofactor for which enzyme

ATPase

37

Se is a cofactor for which enzyme

glutathione peroxidose

38

Cu is a cofactor for which enzyme

cytochrome c oxidase

39

Zn is a cofactor for

superoxidase mutase.

40

Fe is a cofactor for

heme

41

2 types of co-enzymes

1. Co-substrate- temporarily bind and leaves changed
2. Prosthetic group- permanently binds and does not leave changed

42

Ex. of co-substrate

Co-substrates bind and leave changed.

NAD+--> NADH

43

Holoenzyme

protein and non-protein component

44

Enzymes are regulated by what?

1. pH
2. Temperature
3. covalent modifications (phosphorylation)

45

The reaction rate _____ for ever 10 degrees celcius

doubles

46

Enzymes are normally found at what pH

4-8

Except gastric enzymes. They are usually found at pH 2.5

47

How does our stomach have a low pH?

The low pH in our stomach is maintained by H+/K+ ATPases.

H+ is pumped into the lumen of our stomach and combined with Cl-. This makes the stomach more acidic,

48

What do we do when we have heartburn, ulcers or indigestion?

We want to make the stomach less acidic. To do this, we want to inhibit gastric pumps (H+/K+ pumps).

49

Gastric pump inhibitors

-prazole

1. omeprazole
2. lansoprazole
3. esomeprazole

50

bad thing about inhibiting gastric pumps?

can cause hyprochloridia.

51

Kinetics depend on what 3 things:

1. Substrate concentration
2. Enzyme-substrate affinity
3. Vmax.

52

MM plot is a _____ curve and approaches Vmax _______

1. hyperbolic
2. asymptotically- because at a certain point, all of our enzymes are saturated and we cannot go faster.

53

MM plot axes

Y axis- V0
X axis- substrate concentration.

54

LB plot

LB plot is the inverse of MM

Y axis- 1/V0
X axis- 1/[S]

Y indicator= 1/V0
X indicator= -1/Km
Slope= Km/Vmax

55

Metaloenzymes

Enzymes that require metal cofactors

56

If metal ions are chelated, then what happens?

The enzymes will not work.

57

Example of a metaloenzyme?

Hexokinase.
needs Mg2+.

58

Example of a metaloenzyme?

Hexokinase.
needs Mg2+.

59

What happens in lead poisoning?

In lead poisoning, Pb (a metal), will disturb 2 enzymes that are important for the production of Heme.

To treat, we will give the patient (Ca-EDTA and dimercaprol). Pb has a higher affinity for EDTA than Ca and it will diplace.

60

Irreversible inhibitors

[II] will bind to the enzyme PERMENTALY at the active site.

The kinetics are the same as non-competitive.
Vmax- decrease
Km-does not

61

How can we overcome irreversible inhibitors?

Make new enzymes.

62

Allosteric enzymes display _______

cooperativity.

63

How do metabolites bind to allosteric enzymes?

Metabolites will bind NON-COVALENTLY to the allosteric enzyme at sites other than the active site.

64

Metabolites (effectors) of allosteric enzymes can be what?

1. Activators
2. Inhibitors

65

What will activators do to the allosteric enzyme?

Increase affinity and decrease Km

66

What will inhibitors do to the allosteric enzyme?

decrease affinity and increase Km

67

Zymogens are also called

proenzymes