Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biochemistry > Exam 1 > Flashcards

Exam 1 Flashcards

1
Q

What is Work?

A

w

  • force acting over a distance
    • positive = work is done on the system
    • negative = work is done by the system on the surroundings
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define Catabolism

A
  • breakdown of organic compounds to release free energy
    • exergonic reactions
      • free energy is release and used to make ATP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define Enzymes

A
  • proteins that carry out chemical reactions
    • accelerate reaction rates by physically interacting with the reactants to promote chemistry
      • increase the likelihood of reactants interacting productively
  • do NOT affect a reaction ΔG value
  • cannot promote a reaction that has a positive ΔG value
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the 2nd Law of Thermodynamics?

A
  • for a process to be spontaneous, there must be an increase in the entropy (randomness or disorder) of the universe
    • the entropy of the universe is always increasing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 6 major classes of enzymes that are clustered based on the types of reactions they catalyze?

A
  1. Oxidation-Reduction
  2. Group Transfer
  3. Hydrolysis
  4. Addition or Removal
  5. Isomerization
  6. Ligation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

There is a negative free energy change if and only if the entropy of the universe increases.

What parameters provide for a spontaneous reaction?

A

ΔG = ΔH – TΔS

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

What is Heat?

A

q

  • transfer of energy between to objects due to a temperature difference (random molecular motion)
  • 2 types
    • exothermic reaction
      • heat flows out of the system and into the surroundings
    • endothermic reaction
      • heat flows from the surroundings and into the system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why is water so important?

A
  • due to its polarity
    • oxygen draws electrons away from the hydrogens
      • results in oxygen having a partial negative charge and the hydrogens having a partial positive charge
      • b/c of this, can disolve a variety of substances
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define Phototrophs

A

produce energy by trapping sunlight

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

What are Endergonic Reactions?

A
  • reactions that require an input of energy to spontaneously proceed
    • often coupled to exergonic reactions in order to proceed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe Group Transfer Reaction

A
  • functional groups are transferred to a molecule
    ex) pg 431; phosphate group is being transfered
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the equation for overall Entropy?

A

deltaSuniverse = deltaSsystem + deltaSsurroundings

where for the reaction to be spontaneous, deltaSuniverse must be greater than zero

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

Calculate ΔG for a process with a ΔH of 84 kJ and a ΔS of +125 J/K at 298K

A

ΔG = -45,650J or -45.7 kJ

Negative ΔG so this is a spontaneous process

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

If an exothermic reaction has a ΔHsystem = -100 kJ and ΔSsystem = 285 J/K at 25°C, will this reaction occur spontaneously?

A

ΔSuniverse = 0.621 kJ/K

Since this is an exothermic reaction, heat flowed from the system to the surroundings

ΔSuniverse is positive so yes this is spontaneous

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

Describe Oxidation-Reduction Reaction

A

Reactions involve the relay of electrons

  • reduction
    • a compound gains electrions
  • oxidation
    • a compound losses electrons

ex) page 236; reduction of pyruvate to Lactate

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

What do organisms use to speed up the rates of reactions?

A

Biological Catalysts

Enzymes

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

What is Energy?

A

U

  • capacity to do work or generate heat
  • 2 types
    • potential
      • energy due to position or composition i.e. energy that will be released on occurence of some process
    • kinetic energy
      • energy due to motion
        • KE = 1/2mv2​ where m = mass and v = velocity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Covalent Bonds

A
  • a bond that occurs when two nonmetals share electrons
    • nonmetals will share electrons in order to fully occupy their outer energy level
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Ionic Bonds

A
  • the attraction between positively charged metal ions and negatively charged non-metal ions
    • involve the transfer of elections
      • metals readily lose their valence electrons
      • non-metals readily gain electrions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe Addition/Removal Reactions

A
  • functional groups are….
    • added to a molecule to remove a double bond
    • removed from a molecule to form a double bond

ex) pg 510

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

Define Cell

A
  • the lowest level of organization that can perform all activities required for life
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe Hydrolysis Reaction

A
  • a molecule is broke down and water is added to the bond that is broken
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are some Oxygen-containing functional groups?

A
  • carbonyl
    • aldehyde
  • carbonyl
    • ketone
  • carboxylate
  • hydroxyl
    • alcohol
  • Enol
  • Ether
  • Ester
  • Acetyl
  • Anhydride
    • 2 carboxylic acids
25
What is a saturated hydrocarbon?
* an organic compound with only carbon and hydrogen that has all single bonds
26
Gibbs Free Energy
* a reaction that is spontaneous will give a negative change in Gibbs free energy ΔG = ΔH – TΔS
27
In a biochemical reaction, the following enthalpy values are known: Enthalpy of reactants = kJ Enthalpy of products = 550kJ What is the change in enthalpy, and what does this tell you about the reaction?
deltaH = Hproducts - Hreactants = -250 kJ The overall change in enthalpy is negative meaning heat was lost to the surroundings Exothermic Reaction
28
What are some Sulfar-containing functional groups?
* sulfhydryl * disulfide * thioester
29
What is the equation to calculate the deltaS of surroundings?
deltaSsurroundings = -deltaHsystem/T deltaH is from the system if deltaH is negative, then heat flowed from the system to the surroundings (exothermic)
30
What are the two ways organisms can obtain energy?
Chemically (Chemotrophs) Light (Phototrophs)
31
Describe Isomerization Reaction
* the bonds of a molecule are rearranged * the product formed will have the same molecular formula but the atoms will be bonded differently ex) 458
32
What do all cells contain?
* contain a nucleus or nucleoid that contains their DNA (genome; genetic code) * contain a cytoplasm where a variety of metabolic processes occur * contain a plasma membrane that serves as the boundary or barrier for the cell
33
What are some Nitrogen-containing function groups?
* amino * protonated * amido * imine * N-substituded imine * Schiff base * guanidinum * imidazole
34
True or False Biochemistry is organized around carbon, which makes up about 1/2 the dry weight of cells
True
35
What are some examples of things organisms need to do to live?
* maintain their genetic code * replicate and protect * reproduce * pass on the genetic code from generation to generation * metabolize * produce energy which allows organisms to move, breath, fight off infections etc.
36
What is the 1st Law of Thermodynamics?
Conservation of Energy * energy can be converted from one form to another, but the energy of the universe is constant * energy can be neither created nor destroyed
37
Entropy
S * a measurement of the randomness of disorder * unitis J/K
38
Define Enthalpy
* a thermodynamic term that is equivalent to the heat absorbed at constant pressure (units in J) H = U + PV H = enthalph U = energy P = pressure V = volume
39
Define Chemotrophs
produce energy by oxidizing a carbon source from their environment
40
What is a Spontaneous Process?
* a reaction will occur without the input of any additional energy from outside the system * 2nd Law says that a spontaneous reaction results in an increase in the disorder of the universe
41
True or False Thermodynamics in Biochemistry tells you how fast the reaction will go (reaction rates)
False Thermodynamics tells you nothing about reaction rates Only whether or not a reaction will occur spontaneously
42
Define Unsaturated Hydrocarbons
* molecules that do not contain the maximum number of hydrogen atoms * Alkenes = double bond * Alkynes = triple bond
43
The foundation of Biochemistry is based on what four organic biological macromolecules?
1. Proteins 2. Nucleic Acids 1. DNA & RNA 3. Carbohydrates 4. Lipids
44
Describe Ligation Reaction
* two molecules are joined together at the expense of ATP to form one compount * the ATP in these reactions serves as an energy source for the reaction * ATP is not added to the molecule ex) 824
45
Hydrogen bond donor vs. Hydrogent bond acceptor
* donor * group (O, N, S) that is covalently bonded to the hydrogen * acceptor * nearby group (O, N, S) that has a negative charge due to a dipole
46
Define Anabolism
* Small molecules are used to make larger, more complex molecules * endergonic reactions * require the input of free energy (ATP) to occur b/c reactions result in an increase
47
What are the 4 types of Noncovalent Bonds?
1. hydrogen bonds 2. electrostatic interactions 3. van der Waals interactions 4. hydrophobic interactions
48
What is the equation of enthalpy when a system undergoes a change at constant pressure?
deltaH = deltaU + PdeltaV PdeltaV = expression for work done by expansion of gas 1. pressure during chemical reactions is constant 2. volume changes in most biochemical reactions is insignificant 1. PdeltaV = 0
49
What are some Phosphate-containing functional groups?
* phosphoryl * phosphoanhydride * mixed anhydride * carboxylic acid and phosphoric acid * also called acyl phosphate
50
Define Steroisomers
* compounds that have the same molecular formula and some order of atomic connections but differ in molecular arrangement
51
What is Internal Energy?
* the sum of all the energy of a system * can be changed by the flow of work, heat or both * deltaU = q + w
52
What are Exergonic Reactions?
* spontaneous reactions that release free energy
53
Chiral vs. Achiral
* Chiral * a molecule that is not identical in all respects with its mirror image * it is superimposable * Achiral * a molecule that is identical with its micco image * superimposable
54
True of False Enzymes only accelerate a reaction that can occur spontaneously
True Positive ΔG
55
What are Functional Groups?
* give organic compounds diversity * provide compounds with diverse physical and chemical properties * double and triple bonds are functional groups

Biochemistry (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions