1. Fundamentals of Biochemical Reactions

Question 1

What is the free energy equation? (dletaG =…)

Answer 1

ΔG = ΔG°΄ + RTln(Products / Reactants)

Question 2

Keq = ?

Answer 2

Products over Reactants

Question 3

deltaG of ATP -> ADP + Pi

Answer 3

-7.3 kcal / mol

Question 4

deltaG of ATP -> AMP +PPi

Answer 4

-10.9 kcal / mol

Question 5

deltaG of PPi -> Pi + Pi

Answer 5

-4.0 kcal / mol

Question 6

Normal pH of blood?

Answer 6

pH = 7.37 - 7.43

Question 7

Kidneys remove H+ from the blood in the form of ____, and reabsorb _____

Answer 7

H+ removed as NH4+ HCO3- is reabsorbed

Question 8

What are the 6 enzyme classes?

Answer 8

1. Oxidoreductases
2. Trasferases
3. Isomerases
4. Lyases
5. Ligases
6. Hydrolases

Question 9

What do Lyases do?

Answer 9

Add or remove atoms to or from a double bond.

Question 10

What do Lygases do?

Answer 10

Form C-O, C-S, C-N, or C-C bonds with the hydrolysis of ATP

Question 11

Metal ions that act as cofactors (5)

Answer 11

1. Copper (Cu)
2. Iron (Fe)
3. Magnesium (Mg)
4. Selenium (Se)
5. Zinc (Zn)

Question 12

Optimal temperature for most human enzymes

Answer 12

37 degrees celcius

Question 13

Optimal pH for most human enzymes (range, excludes pepsin)

Answer 13

pH between 4-8

Question 14

Proton pump inhibitors affect what enzyme?

Answer 14

H+/K+ ATPase

Question 15

Where is H+/K+ ATPase found, and what is its function?

Answer 15

Found in the Parietal Cells lining the gastric lumen

Pumps H+ into the lumen where it combines with Cl- to become HCL

Question 16

What disease of the stomach can omeprazole cause, and what are its symptoms?

Answer 16

Hypochlorhydria

Symptoms:

• Reduced absorbtion of nutrients
• Increased sensitivity to food poisioning
• Reduction of gastric enzyme efficiency (especially pepsin, gastric amylase, and gastric lipase​)​​​

Question 17

Binding of Noncompetitive vs Uncompetetive inhibitors

Answer 17

Noncompetetive:

Binds to either the empty Enzyme or the Enzyme-Substrate complex at a site other than the substrate binding site

Uncompetitive:

Binds to only the Enzyme-Substrate complex at a site other than the binding site.

Question 18

In conceptual terms, what does Km represent?

Answer 18

The amount of substrate, in moles, needed to reach 1/2 Vmax

Question 19

Characteristics of Competitive inhibition

Answer 19

• No Effect on Vmax
• Increase in Km
• Larger substrate concentration needed to achieve 1/2 Vmax

Question 20

Characteristics of Noncompetitive inhibition

Answer 20

• Decrease in Vmax
• Km stays the same (the arch moves down)
• Inhibitor effects cannot be overcome by increasing substrate concentration. (Vmax is lowered)

Question 21

Characteristics of Uncompetitive inhibition

Answer 21

• Km and Vmax are decreased by the same factor, resulting in paralel LB graphs

Question 22

What is the example given in the slides of a chelating agent?

Answer 22

EDTA: Ethylene Diamine Tetraacetic Acid

Question 23

Symptoms of lead poisioning?

Answer 23

• Irritability
• Sideroblastic Anemia
• Abdominal pain
• Headaches

Question 24

What two medications are given for lead poisoning?

How do these work?

Answer 24

1. Ca-EDTA
2. Dimercoprol

Lead likes EDTA more than Calcium does, so it binds preferetially to the EDTA and forms Pb-EDTA, which is excreted out of the body.

Dimercoprol attaches to the regions of enzymes affected by lead that lead would like to attach to - thus slowing the effects of lead toxicity.

Question 25

**Enzyme Inactivation** resembles which type of inhibiiton?

Answer 25

**Noncompetitive** Vmax decreases, but Km stays the same. (There are less enzymes to do the reaction quickly, but affinity stays the same)

Question 26

What are the four enzymatic markers for MI?

Answer 26

1. **Troponin (Specifically cTn-I)** 2. CK-MB (Muscle Brain Creatine Kinase) 3. LDH-1 (Lactate Dehydrogenase) 4. AST/SGOT1 (Aspartate aminotransferase / Serum Glutamate oxaloacetate transaminase) \* Note: These are presented in order from quickest to present to longest to present.

Question 27

When is Troponin the most sensitive for an MI?

Answer 27

10-24 hours following MI

Question 28

Enzyme related to the diagnosis of **Bone Disease**

Answer 28

**Alkaline phosphatase** The reality is a bit more complex than this, but this enzyme is present in bone, and is freed when there is damage. This enzyme is also a marker for liver disease.

Question 29

Enzyme**_s_** related to the diagnosis of **Obstructive Liver Disease**

Answer 29

**Sobitol Dehydrogenase** **Lactate Dehydrogenase (LDH - 5)**

Question 30

Enzyme related to the diagnosis of **Prostatic Cancer**

Answer 30

**Acid Phosphatase**

Question 31

Enzyme related to the diagnosis of **Acute pancreatitis**

Answer 31

**Amylase / Lipase**

Question 32

Enzyme**_s_** related to the diagnosis of **Muscular Distrophy**

Answer 32

**Aldolase** Helps convert glucose into energy in muscle cells **ASH** (I have no idea what this is)

Question 33

Enzyme related to the diagnosis of **Liver Disorder**

Answer 33

**CK-MM** Creatine Kinase - Muscle *WITH ALSO HAVING HIGH* **ALT AST**

Question 34

What is the graph shape for **Michaelis Menton** graphs?

Answer 34

Hyperbolic

Question 35

What is the graph shape for **Allosteric** enzyme kinetics?

Answer 35

Sigmoidal