Properties of Biological Molecules

Question 0

What is the Second Law of Thermodynamics

Answer 0

The total entropy of a system plus that of its surroundings always increases. Entropy may be decreased locally if entropy of universe is increased by an equal or greater amount

Question 1

What is the First Law of Thermodynamics?

Answer 1

Total energy of a system and its surrounds are constant. Energy is neither created or destroyed

Question 2

Purpose of Glycolysis

Answer 2

Generating energy to maintain ionic disequilibrium to allow for continued electrical depolarization

Question 3

What drives a reaction?

Answer 3

1. Increase the concentrations of reactants

2. Decrease the concentration of products

Question 4

What is Mass Action

Answer 4

Le Chatelier’s Principle which is the concept of concentration driving the reaction

Question 5

Free energy is spontaneous when?

Answer 5

Delta G is negative and energy is released and spontaneous

Question 6

What is the free energy equation?

Answer 6

Delta G = Delta H - T(Delta S)

Question 7

Give an example of a covalent bond. What is the strength of covalent bonds

Answer 7

C-C bond and it is the strongest bond

Question 8

What makes a bond strong

Answer 8

The amount of energy that must be expended to break them

Question 9

What are electrostatic interactions. Give the equation

Answer 9

A charged group of one molecule atracts an opposite charge of another
kq1q2/Dr

Question 10

In the equation E = kq1q2/Dr, What is the relation of r to E. What is the relation of D to E

Answer 10

R is the distance between two charges. As distance gets closer the greater the energy. Greater the D the lower the E

Question 11

E=kq1q2/Dr What does the D mean

Answer 11

D is Dielectric concentration of the solvent, the environment. If the environment is water the water is polar (80) its going to diminish the E. Bigger D smaller E. But hydrophobic world is the D is small so E is up (Hexane 2)

Question 12

Hydrophobic Effect

Answer 12

Water does not like to interact with hydrophobic molecules. Forms a crystalline structure around the droplet and is almost like ice.

Question 13

Van der Waals Interactions

Answer 13

The basis of a van der Waals interaction is that the distribution of electronic charge around an atom fluctuates with time.

Question 14

Hydrogen Bonds

Answer 14

These interactions are fundamentally electrostatic interactions.

Question 15

2 properties of water

Answer 15

1. Water is a polar molecule - asymmetric, bent

2. Highly cohesive - interact strongly with one another

Question 16

Thermodynamics vs Reaction Velocity

Answer 16

Thermo - Whether the reaction will proceedwithout the input of energy, not indicative of velocity
Velocity - Reaction velocity is increased bya catalyst – an enzyme

Question 17

Acid-Base Reactions

Answer 17

– Weak acid dissociates in water, releasing a proton and its conjugate base
– Weak base combines with protons in water, forming itsconjugate acid

Question 18

What is pH

Answer 18

The concentration of hydrogen ions in solution

pH = -log(H+)

Question 19

pH of 7.0 is equal to….

Answer 19

pH 7.0 refers to a solution for
which −log[H+] = 7.0, and so log[H+] = −7.0
and [H+] = 10log[H+] = 10^-7 = 1.0 × 10−7 M.

Question 20

Equilibrium constant (k) for the dissociation of water is equal to ?

Answer 20

1.8x10 ^-16

=[H+][OH−]/[H2O]

Question 21

What is the Henderson–Hasselbalch equation?

Answer 21

pH = pKa + log([A−]/[HA])

Question 22

Why is pH range for blood and inside the cell = 7.36-7.43?

Answer 22

Proteins must maintain structure and function

Question 23

Describe the acid levels in blood when hyperventilating

Answer 23

When hyperventilating-it is alkolosis and pH goes up. Increasing the rate loss of CO2. carbon dioxide is a by-product of metabolism, and carbon dioxide combines with water to form carbonic acid. Rapid elimination of acidic products of metabolism results in alkalosis

Question 24

What is a buffer? Give an example

Answer 24

Substance that will keep the pH from changing. Bicarbonate can pick up a proton if protons are added to keep the protons being added to the solution. It can also add a proton to a solution. Reversibly bind protons and has a pK

Question 25

Hypo-ventilating causes pH to….

Answer 25

Lower. Failure to eliminate acidic products of metabolism results in acidosis

Question 26

What happens to pH when one vomits vs has diarrhea?

Answer 26

Vomit burns because of stomach acid so rapid loss of acid causes alkolosis
Diarrhea causes bicarbonate to be lost so acidosis

Question 27

When is the buffer at its maximum?

Answer 27

When pH = pKa

Question 28

When pH is lower than pKa then

Answer 28

the acidic form is in higher concentration and there is high affinity (not give up proton very easily until the pH gets to the pK value)

Question 29

When pH is higher than the pKa then

Answer 29

It is more deprotenated and low affinity

Question 30

If H2PO4 goes to HPO4. Which one is the conjugate acid making the other the conjugate base?

Answer 30

HPO4 is the conjugate base (A-)

H2PO4 is the conjugate acid (HA)

Question 31

What is Delta G 0 Prime?

Answer 31

Laboratory value that is determined. Standard free-energy change. Delta G 0 Prime = -RT ln K’eq

Question 32

pK of a carboxyl group has high or low pK

Answer 32

low

Question 33

The pK for a amine group has a low or high pK?

Answer 33

High