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Flashcards in Section 1 Deck (41)
1

pH of arterial plasma

7.35-7.45

2

pH of extracellular fluid

6.8-7.8

3

pH within cells

6.9-7.4

4

If pH

acid

5

If pH>pKa, then what form predominates?

basic

6

what is the buffer system of blood?

bicarbonate

7

What is the intracellular buffer system?

phosphate

8

What is this condition?
increase in partial pressure of CO2

resipratory acidosis

9

What is this condition?
decrease in partial pressure of CO2

respiratory alkalosis

10

What is this condition?
decrease in HCO3- concentration

metabolic acidosis

11

What is this condition?
increase in HCO3- concentration

metabolic alkalosis

12

What condition is due to decrease in lung function and how will the body do to compensate?

Respiratory Acidosis
- kidneys will try to compensate by increasing bicarbonate
- all compensatory reaction by the kidneys will take several days

13

What condition is due to hyperventilation and what will the body do to compensate?

Respiratory Alkalosis
- kidneys will try to compensate by excreting bicarbonate in urine

14

What condition can be caused by decreased kidney function or body trying to compensate for an already existing acidosis, such as DKA? How will the body try to compensate?

Metabolic Acidosis
- lungs will attempt to compensate by "blowing off" CO2
- this effect will take place within minutes and complete within 12 - 24 hours

15

What condition can be caused by an excess administration of bicarbonate or loss of H+ (from prolonged vomiting or use of diurectics)? How will the body compensate?

Metabolic Alkalosis
- lungs will attempt to compensate by breathing less (hypoventilation), trying to keep as much CO2 as possible

16

What type of protein structure is this?
structure results from hydrogen bonding interactions between C=O and H-N of the backbone

Secondary structure

17

What type of protein structure is this?
subunits associate with each other through non-covalent interactions?

quaternary

18

What type of protein structure is this?
sequence of amino acid residues in a polypeptide chaing
- determines 3-D structure and biological function of the protein

primary

19

What type of protein structure is this?
non-covalent interactions are the major element in formation of this structure (H-bonding, hydrophobic forces and van der Waal's)

tertiary

20

What type of enzyme is this?
catalyzes cleavage of bonds with water

hydrolases
Ex. glucosidases, ATPases

21

What type of enzyme is this?
catalyzes redox reactions, transfer of electrons

oxidoreductase
Ex. NAD+>>NADH

22

What type of enzyme is this?
catalyzes transfer of functional groups

transferases
Ex. kinases, aminotransferases

23

What type of enzyme is this?
catalyzes formation of bonds between carbons and other atoms

ligases
Ex. synthase, synthetase, carboxylase

24

What type of enzyme is this?
cleaves bonds without water

lyases
Ex. aldose B

25

What type of enzyme is this?
changes stereochemistry

isomerase

26

Holoenzyme

apoenzyme with prosthetic group
- active

27

Apoenzyme

apoenzyme without its prosthetic group
- inactive

28

Vmax, conditions

more substrate will not increase reaction rate, but more enzymes will
- does not depend of concentration of subtrate

29

Km, conditions

- more enzymes will not change this value

30

What does a low Km mean?

increase substrate affinity
- takes more substrate to be at Vmax/2
this explains why glucokinase can turn over more G6P from glucose than hexokinase

31

What does a high Km mean?

decrease substrate affinity
- takes only small amount of substrate to be at Vmax/2

32

Conditions of competitive inhibition

Vmax - no change because it's independent of substrate concentration
Km increases (substrate concentration dependent)
- less substrates are binding

33

Conditions of non-competitive inhibition

Vmax decreases (number of enzymes changed due to the inhibition)
Km - no change
- fewer working enzymes

34

Gs G-proteins

stimulates adenylate cyclase to form cAMP

35

Gi G-proteins

inhibits adenylate cyclase

36

Gq G-proteins

stimulates phospholipase C to form IP3/DAG

37

Which is better at binding to oxygen during low levels of O2, myoglobin or hemoglobin?

myoglobin

38

What is better at binding to oxygen during high levels of O2, myoglobin or hemoglobin?

hemoglobin

39

Which form of Hb has a higher affinity for O2, T or R?

R form

40

What kind of allosteric modulator is O2 on Hb? What about 2,3-BPG, CO2 and H+?

O2 is a positive allosteric modulator of Hb, all the others are negative allosteric modulators of Hb

41

CO2 can bind to N-terminal ends of Hb subunits and form carbamates, what effect will this have on the structure of Hb?

stabilizes T-form, facilitate release of O2 in peripheral tissues