Brainscape's Knowledge GenomeTM

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


See full index

LDSCI211 (Biochem 1) > Metabolism and Bioenergetics > Flashcards

Metabolism and Bioenergetics Flashcards

1
Q

Define metabolism

A

sum of all chemical transformation that occur in living cells

metabolism = catabolism + anabolism

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

1st law of thermodynamics?

A

e=mc^2

total energy of the universe is constant. It can’t be created or destroyed but can be transformed

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

2nd law of thermodynamics?

A

the universe has a tendency to increase disorder.

more disorder = spontaneity

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

3rd law of thermodynamics?

A

as the temp approaches absolute zero (0k or -273.8deg ) atomic motion stops (but electronic motion is not affected)

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

What happens during catabolism?

A

break down of energy containing compounds.

releases energy as ATP and reduced electron carriers (NADH)

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

How can energy be released?

A

as ATP of reduced electron carriers: NACH, NACPH, FADH2

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

Define Gibbs free energy

A

the energy available in a system

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

What is the Gibbs free energy equation?

A

G = H - TS

H=enthalpy
S=entropy
T=temp in K (25 C = 298k)

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

What is enthalpy?

A

heat content reflecting the number and type of bonds

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

What is entropy?

A

extent of disorder in the system

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

do organized systems have high or low entropy?

A

low entropy (low disorder)

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

When energy is released, what is the sign of delta G? Is this spontaneous?

A

negative

yes

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

When energy is absorbed, what is the sign of delta G?

A

positive

no

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

What is delta G naught?

What is delta G prime naught?

A

standard free energy change at 25C, 1atm, 1M initial conc of solutions. Used by chemists/physicists

biochemical standard free energy change at pH 7. used by biochemists

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

what is the delta G in oxidation of glucose?

A

deltaG = -2840kJ/mol

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

is the oxidation of glucose spontaneous or not spontaneous?

A

spontaneous (because negative delta G)

17
Q

what is the terminal electron acceptor?

A

oxygen

because it

18
Q

delta G gives no information on the reaction rates. T or F?

A

T

19
Q

At equilibrium, delta G prime naught = ?

A

delta G prime naught = -RTln(K’eq)

K’eq = products / reactants

20
Q

what is the relationship between delta G prime naught and K’eq?

A

directly proportional

21
Q

What does a small or big K’eq mean?

A

small K’eq = +delta G prime naught = not spontaneous = favours substrate

big K’eq = -delta G prime naught = spontaneous = favours product

22
Q

why are reactions coupled together?

A

to drive unfavourable steps in a metabolic process

23
Q

when you find the overall K’eq, do you multiply or add K’eq values?

A

multiply

24
Q

what are referred to as high energy compounds?

A

when delta G prime naught of hydrolysis is bigger than -25kJ/mol

25
Q

What are the 4 chemical basis for the high energy stored in the phosphoanhydride bonds?

A
  1. 4 negative charges (repulsion is from bond stress. hydrolysis releases electrostatic stress)
  2. Resonance delocalization of PO4^2-
    (delocalization = more molecules = more disorder = higher delta S = higher delta G)
  3. ADP ionizes releasing H+ (more molecules = increases delta S)
  4. ATP hydrolysis increases solvation of ADP and Pi
    (need less h20 molecules to solvate ATP than inorganic phosphate = increases randomness = increases E)
26
Q

what is solvation

A

formation of sphere of hydration

27
Q

what is a hydride

A

proton with two electrons

H-

transports electrons in biological systems

28
Q

what is the general formula for half cell reactions?

A

Ared Aox + ne-
Box + ne- Bred

overall: Ared+box Bred + Aox

29
Q

what does the equilibrium point for REDOX reactions depend on?

A

relative affinity of Aox and Box for electrons

30
Q

in the reduction of Fe3+ by Cu+, which is the oxidizing and reducing agent?

A

Fe3+ is the electron acceptor (oxidizing agent)

Cu+ is the e donor (reducing agent

31
Q

which agent has an excess of e-?

A

reducing agent

32
Q

which agent picks up e-?

A

the oxidizing agent

33
Q

what are the half cell reactions of Fe3+ by Cu+?

A

Cu+ Fe2+

overall: Fe31+ + cu+ Fe2+ + Cu2+

34
Q

What is E naught?

A

reduction potential tendency to gain electrons

35
Q

does reducing potential decrease or increase down the ETC?

A

decrease

36
Q

what does a large positive Eprime naught mean?

A

bad reducing agent. good oxidizing agent

wants to take electrons

ex: oxygen

37
Q

what does a negative E prime naught mean?

A

good reducing agent. bad oxidizing agent

wants to give away electrons

ex: H2

38
Q

Is the beginning or the end of the ETC a better reducing agent?

A

the agent in the beginning of the chain will be the best reducing agent. (decreases as you move down)

LDSCI211 (Biochem 1) (8 decks)

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