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Flashcards in Exam 1 Deck (66):
1

What is the terminal e- acceptor in aerobes?

oxygen (O2)

2

What is the terminal e- acceptor in anaerobes?

CO2, Fe, NO2, other stuff

3

What type of energy source do autotrophs use?

simple chemicals ie: CO2

4

What type of energy source do heterotrophs use?

complex chemicals ie: glucose

5

What is catabolism?

breaking down of molecules = release free energy

6

Are hydrolysis and oxidation reactions examples of anabolism or catabolism?

catabolism

7

What is anabolism?

ionizing/synthesizing molecules = use free energy

8

Are reduction and condensation reactions examples of anabolism or catabolism?

anabolism

9

What is a dehydrogenase?

a hydride

10

What is NAD+ used as in glycolysis?

cofactor - hydride acceptor, e- acceptor

11

What is Le Chatlier's principle?

process - a system at equilibrium will try to remain in equilibrium

12

What is Hess's Law?

reactions can be added together from different sets of reactions

13

How to convert from Celcius to Kelvin?

add 273

14

What are standard conditions? (M, temp in Celcius, and pressure)

1M, 25C, 1atm

15

Why are the standard conditions not adequate for biological conditions?

pH does not = ~7 if [H+] = 1M

16

What is the transformed standard state?

pH=~7, 1M solutes, 25C, 1atm

17

What does transformed mean when talking about standard conditions?

standard conditions have been altered to become adequate for biological conditions

18

What is the thermodynamics equation?

∆Gº = ∆Gº' + RT ln(Q or K)

19

What does "Q" stand for in thermodynamics?

concentrations at new state

20

What does "K" stand for in thermodynamics?

equilibrium conditions

21

What does exergonic mean?

entropy, spontaneous (-∆G)

22

What does endergonic mean?

enthalpy, non-spontaneous (+∆G)

23

What is Acetyl-CoA?

acetate covalently bound to coenzyme A via a thioester.

24

What does DHAP stand for?

Dihydroxyacetone phosphate

25

Where does the Pentose Phosphate Pathway occur?

adipose and liver

26

Where does Lactic Acid Fermentation occur?

brain and muscle

27

Where does Glycolysis occur?

brain and muscle

28

Where does Glucogenesis occur?

liver (70%) and kidneys (30%)

29

What role does Mg2+ play in Glycolysis?

true co-substrate

30

What significant role does hexokinase play in relation to glucose?

phosphorylates glucose = influx of glucose into cell --- phosphorylation prevents glucose going out of the cell

31

What is hexokinase allosterically controlled by?

glucose-6-phosphate (G6P)

32

What is a hemiketal?

RO-CR-OH

33

What is a hemiacetal?

RO-CH-OH

34

What is a hemiacetal?

RO-CH-OH

35

What is an imminum?

a protonated Schiff base (an e- sink!)

36

What is an imine structure?

RC=N–R/H

37

What is an imminium structure?

RC=NH(+)–R

38

How is PFK-1 allosterically controlled?

by ATP binding to the allosteric site

39

How many binding sites PFK-1 has?

2 = active and allosteric sites

40

What are Class I Aldolases?

(for plants/animals) lysine = imminium ion

41

Based on Le Chatlier's Principle, what direction does the reaction go if there is more product than substrate?

leads to substrate formation (backward reaction)

42

Based on Le Chatlier's Principle, what direction does the reaction go if there is more substrate than product?

leads to product formation (forward reaction)

43

What are Class II Aldolases?

(for bacteria and fungi) Zinc = coordinate bond with O=C...

44

In step 6 of Glycolysis, what acts as the nucleophile?

Cysteine

45

In step 6 of Glycolysis, what acts as the general base?

Histidine

46

What intermediates are formed in step 2 of Glycolysis? (Gluc>G6P)

enolate and enediol

47

What intermediates are formed in step 4 of Glycolysis? (F-1,6-P>DHAP/G3P)

imminium and eneamine

48

What intermediates are formed in step 5 of Glycolysis? (DHAP>G3P)

enediol

49

What intermediates are formed in step 6 of Glycolysis? (G3P>1,3-BPG)

thioester

50

What steps in Glycolysis use ATP?

Steps 1 and 3

51

What steps in Glycolysis make ATP?

Steps 7 and 10

52

What product in Glycolysis is considered a "high-energy intermediate"?

1,3-BPG

53

What organisms use the phosphoglycerate mutase via the INTERmolecular pathway? What intermediate does this form?

yeast and rabbit, phosphohistidine intermediate

54

What organisms use the phosphoglycerate mutase via the INTRAmolecular pathway? What intermediate does this form?

bacillus and wheat germ, phosphoserine intermediate

55

In Enolase used in step 9 of Glycolysis, what acts as the general base?

Lysine

56

In Enolase used in step 9 of Glycolysis, what acts as the general acid?

Glutamate

57

In step 9 of Glycolysis, what is the role of Mg2+?

polarizes oxygens near the acidic alpha-H in order for a base to pick it up

58

Which pathway and what alternative will Galactose undergo?

Le Loir pathway to make G6P

59

What enzymes and products will be formed from Mannose?

(HK) = M6P --> (phophomanno-isomerase) = F6P

60

What enzymes and products will be formed from Glycerol?

(glycerol kinase) = glycerolphosphate = DHAP

61

What enzyme is used to convert starch/glycogen (from food) into glucose?

amylase

62

What enzymes are used and steps will Fructose undergo?

(Fructokinase) =F16 --> (F16 aldolase) = step 5 glycolysis

63

What will Fructose form with hexokinase?

F6P

64

What enzymes used and products formed from Sucrose?

(sucrase) = glucose & fructose

65

What enzymes and intermediates will endogenous glycogen use to form G6P?

1-phosphorylase, 2- glycogen debranching enzyme, 3- phosphoglucomutase

66

What can Trehalose form? With what enzyme?

(trehalase) = 2 glucose