Biochemistry

Question 1

How do enzymes affect chemical reactions?

Answer 1

Stabilizes the transition state, thus LOWERING THE ACTIVATION ENERGY of a reaction (DOES NOT stabilize substrate and DOES NOT affect the free energy of a reaction)

Question 2

Intermolecular Covalent Bonds

Answer 2

ex: disulfide bridges; creates structural rigidity

Question 3

pH dependence of aggregation

Answer 3

NEEDS to have pH dependent side chains

Question 4

Lipase

Answer 4

hydrolyzes triacylglycerides

Question 5

What type of bond connects glucose molecules in glycogen?

Answer 5

alpha- 1,4- glycosidic bond

Question 6

Ribose Structure

Answer 6

Question 7

Fructose

Answer 7

Question 8

Glycogen is very branched due to ___

Answer 8

alpha-1,6- glycosidic bonds

Question 9

How many fused rings in a steroid?

Answer 9

4 rings-

Question 10

Action Potential- NA+ in during what stage

Answer 10

Depolarization

Question 11

Action Potential- K+ ions out

Answer 11

repolarization

Question 12

Maintenance of resting potential relies on Na+/K+ atpase. How many molecules go in/out of cell?

Answer 12

For every 2 K+ ions brought into cell, 3 Na+ ions move out of the cell

Question 13

how do transcription factors regulate the expression of other genes?

Answer 13

by binding to the promoter or enhancer of the gene located on the DNA

Question 14

How do hydrophobic molecules enter the cell

Answer 14

SIMPLE DIFFUSION

Question 15

What does ATP hydrolysis produce

Answer 15

ADP + inorganic P

Question 16

Lipid Rafts

Answer 16

cholesterol rich domains w/in the membrane

Question 17

Microtubules

Answer 17

bind to chromosomes at the level of the kinetochore and regulate their migration towards the opposite poles of a cell during anaphase

Question 18

Enzymes can change chem rxns through:

Answer 18

1. co localizing substrates
2. altering local pH
3. altering substrate shape

Question 19

mRNA levels can

Answer 19

increase and decrease

Question 20

mature erythrocytes

Answer 20

cells that DO NOT contain DNA

Question 21

Virus & bacteria cultures

Answer 21

animal viruses can only infect animal cells, not bacteria. Therefore, animal viruses cannot grow in agar plates w/ bacteria

Question 22

high levels of cirulating glucocorticoids in the blood will cause…

Answer 22

increased protein degradation in various tissues, including muscles

Question 23

gluconeogene

Question 24

All amino acids (except glycine) are…

Answer 24

are all chiral & L-amino acids (except glycine)

Question 25

Glycine the AA is

Answer 25

achiral