BIOC 3021 Exam 1, Biochem 3021 - Exam 1| Ques ons
and answers | Updated
What are the major elements in living organisms?
C, H, O, N
What are the minor elements in living organisms?
P, Na, K, Ca, Mg, S, Cl
What are trace elements in living organisms?
Fe, Zn, Cu
What are the 4 types of chemical bonds?
1. Covalent
2. Ionic
3. Hydrogen Bonds
4. Weak Non-Polar Interac-ons
- van der Waals
- hydrophobic interac-ons
What are the 5 unique proper-es of water?
1. Cohesiveness/adhesiveness
2. High heat capacity
3. High heat of vaporiza-on
4. Expansion upon freezing
5. Versa-lity as a solvent
What is a Bronsted Acid?
What is an Bronsted Base?
Acid = proton donor
Base = proton acceptor
How do you calculate pH?
-log[H3O+]
What is the Henderson-Hasselbalch Equa-on?
,pH = pKa + log[A-]/[HA]
How do you calculate the buffer range of a solu-on?
pKa +/- 1
What is the carbonic acid/bicarbonate buffer system? What are its benefits?
CO2 + H2O <-> H2CO3 <-> HCO3- + H+
pKa = 6.1, but CO2 can be removed or retained by respira-on which can shi@ equilibrium.
Oxida-on Levels of Carbon
Reduced -> Oxidized
Alkane, Alcohol, Aldehyde, Ketone, Carboxylic Acid, Carbon Dioxide
Catabolism
releases energy by oxidizing carbon atoms by moving them to a higher oxida-on state
Anabolism
uses energy to reduce carbon atoms by moving them to a lower oxida-on state
Reduced carbon
contains energy that the cell can use. because it is fully reduced, it can be oxidized by using
oxygen as the oxidizing agent and thus release the energy
Oxidized carbon
has no energy that the cell can capture, only plants can extract energy and convert it to food
source (photosynthesis)
Stereoisomers
D (R in organic chemistry) and L (S in organic chemistry)
L is the preferred form in nature
Non-Polar Amino Acids
Alanine (Ala)
Valine (Val)
Leucine (Leu)
IsoLuecine (Ile)
Methionine (Met)
, Proline (Pro)
Phenylalanine (Phe)
Tryptophan (Trp)
What is the pKa of Cysteine?
8.3
What is the pKa of Aspar-c Acid?
4.1
What is the pKa of Glutamic Acid?
4.1
What is the pKa of Tyrosine?
10.9
What is the pKa of His-dine?
6.0
What is the pKa of Lysine?
10.8
What is the pKa of Arginine?
12.5
What amino acid can form Disulfide bonds?
Cysteine
What is the charge of an amino acid at...
1. pH 7
2. pH 1
3. pH 11
1. 0 (ZwiLer ion)
2. +1
3. -1
What is an essen-al amino acid?
and answers | Updated
What are the major elements in living organisms?
C, H, O, N
What are the minor elements in living organisms?
P, Na, K, Ca, Mg, S, Cl
What are trace elements in living organisms?
Fe, Zn, Cu
What are the 4 types of chemical bonds?
1. Covalent
2. Ionic
3. Hydrogen Bonds
4. Weak Non-Polar Interac-ons
- van der Waals
- hydrophobic interac-ons
What are the 5 unique proper-es of water?
1. Cohesiveness/adhesiveness
2. High heat capacity
3. High heat of vaporiza-on
4. Expansion upon freezing
5. Versa-lity as a solvent
What is a Bronsted Acid?
What is an Bronsted Base?
Acid = proton donor
Base = proton acceptor
How do you calculate pH?
-log[H3O+]
What is the Henderson-Hasselbalch Equa-on?
,pH = pKa + log[A-]/[HA]
How do you calculate the buffer range of a solu-on?
pKa +/- 1
What is the carbonic acid/bicarbonate buffer system? What are its benefits?
CO2 + H2O <-> H2CO3 <-> HCO3- + H+
pKa = 6.1, but CO2 can be removed or retained by respira-on which can shi@ equilibrium.
Oxida-on Levels of Carbon
Reduced -> Oxidized
Alkane, Alcohol, Aldehyde, Ketone, Carboxylic Acid, Carbon Dioxide
Catabolism
releases energy by oxidizing carbon atoms by moving them to a higher oxida-on state
Anabolism
uses energy to reduce carbon atoms by moving them to a lower oxida-on state
Reduced carbon
contains energy that the cell can use. because it is fully reduced, it can be oxidized by using
oxygen as the oxidizing agent and thus release the energy
Oxidized carbon
has no energy that the cell can capture, only plants can extract energy and convert it to food
source (photosynthesis)
Stereoisomers
D (R in organic chemistry) and L (S in organic chemistry)
L is the preferred form in nature
Non-Polar Amino Acids
Alanine (Ala)
Valine (Val)
Leucine (Leu)
IsoLuecine (Ile)
Methionine (Met)
, Proline (Pro)
Phenylalanine (Phe)
Tryptophan (Trp)
What is the pKa of Cysteine?
8.3
What is the pKa of Aspar-c Acid?
4.1
What is the pKa of Glutamic Acid?
4.1
What is the pKa of Tyrosine?
10.9
What is the pKa of His-dine?
6.0
What is the pKa of Lysine?
10.8
What is the pKa of Arginine?
12.5
What amino acid can form Disulfide bonds?
Cysteine
What is the charge of an amino acid at...
1. pH 7
2. pH 1
3. pH 11
1. 0 (ZwiLer ion)
2. +1
3. -1
What is an essen-al amino acid?
