FINAL EXAM (Old Chapters)

Question 1

What is a peptide bond?

Answer 1

The bond formed between two amino acids.

The amine from one AA condenses onto the carboxylic acid of the other AA.

(condenses = water is released)

Question 2

Why are peptide bonds planar?

Answer 2

Peptide bonds between the amine group and the carboxyl group of two amino acids have ~40% double bond character due to resonance from the lone pair e- on the nitrogen into the C=O bond making the amide bonds rigid.

This rigidity makes the peptide bonds planar.

(Meanwhile, the bonds on either side of the alpha-carbon can rotate.)

Question 3

What are the 5 types of Secondary Structures of proteins?

Answer 3

alpha helices
beta sheets
reverse turns & loops (random coils)
coiled coils
superhelical cables

Question 4

Reverse Turns & Loops AKA

Answer 4

random coils

Question 5

Describe a Coiled Coil

Answer 5

Two alpha-helices wrapped around eachother like two telephone cords

Question 6

Describe a Superhelical Cable

Answer 6

Three alpha-helices wrapped around eachother like three telephone cords

Question 7

What are the 5 Classes of Lipids + a Function of each?

Answer 7

• Free Fatty Acid (fuel)
• Triacylglycerols (store fatty acids)
• Phospholipids (plasma membranes)
• Glycolipids (are connected to carbs and found in membranes containing sugars)
• Steroids (hormones)

Question 8

Class 1 of Lipids

Answer 8

Free Fatty Acids
(fuel source)

Question 9

Class 2 of Lipids

Answer 9

Triacylglycerols
(Store Fatty Acids)

Question 10

Class 3 of Lipids

Answer 10

Phospholipids
(plasma membranes)

Question 11

Class 4 of Lipids

Answer 11

Glycolipids

(found in membranes and are attached to sugars)

Question 12

Class 5 of Lipids

Answer 12

Steroids
(hormones)

Question 13

Name All the Intermediates in Glycolysis

Answer 13

Glucose

Glucose 6-Phosphate

Fructose 6-Phosphate

Fructose 1,6-Bisphosphate

Glyceraldehyde 3-Phosphate (GAP) & Dihydroxyacetone Phosphate (DHAP)

1,3-Bisphosphoglycerate

3-Phosphoglycerate

2-Phosphoglycerate

Phosphoenolpyruvate

Pyruvate

Question 14

Glucose –> Glucose 6-Phosphate
rxn type

Answer 14

phosphorylation

Question 15

Glucose 6-Phosphate –> Fructose 6-Phosphate
rxn type

Answer 15

isomerization

Question 16

Fructose 6-Phosphate –> Fructose 1,6-Bisphosphate
rxn type

Answer 16

phosphorylation

Question 17

DHAP –> GAP
rxn type

Answer 17

isomerization

Question 18

GAP –> 1,3-Bisphosphoglycerate
rxn type

Answer 18

oxidation + phosphorylation

Question 19

Phosphoenolpyruvate –> Pyruvate
rxn type

Answer 19

tautomerization

Question 20

What is the purpose of the Citric Acid Cycle?

Answer 20

Acetyl CoA is combined w/ oxaloacetate. The carbons are broken down into CO2 to extract E in the form of NADH and FADH2 which can be taken through the electron transport chain to generate more ATP.

Question 21

What is the key intermediate regenerated in the Citric Acid Cycle?

Answer 21

oxaloacetate

Question 22

What is the purpose of the Electron Transport Chain?

Answer 22

Energy from NADH & FADH2 generated in the Citric Acid Cycle reduces O2 to H2O. H+ is shuttled out of the matrix across the inner mitochondrial membrane. H+ “falls” back into the matrix through ATP Synthase embedded in the inner membrane of the mitochondria. As the H+ ions fall through the ATP Synthase back into the matrix, ATP synthase converts ADP into ATP

Question 23

What is the purpose of the Proton Gradient?

Answer 23

The difference in concentrations of H+ ions (the proton gradient) allows H+ to “fall” through ATP Synthase. This movement allows ATP Synthase to rotate and convert ADP into ATP.