Unit 2, L19 Acid Base 1

Question 1

Too much acid is what

Answer 1

Acidosis

Question 2

Too little acid is what

Answer 2

Alkalosis

Question 3

ECF pH is what range, normally, and what concentration of H+

Answer 3

7.35-7.45, and 40 nM

Question 4

Plasma levels depend on

Answer 4

Metabolism of ingested food
Secretions of GI
De novo synthesis of acid and base from metabolism of stored fat and glycogen
Changes in production of CO2

Question 5

When we have O2 and insulin, what happens to the fats and carbohydrates?

Answer 5

Turn into H2O and CO2 and get sent to the lungs

Question 6

In anaerobic conditions or if we deplete insulin, or if we ingest lots of proteins, or have fecal HCO3 loss, what will all of this produce?

Answer 6

HA in its acid form + NaHCO3

Question 7

HA + NaHCO3 goes to what and where do the byproducts go

Answer 7

HA + NaHCO3 turns to NaA + H2O + CO2

H2O and CO2 go to the lungs
NaA turns into NEAP, which goes to the kidneys

Question 8

Two key processes of acid base balance

Answer 8

1) Excretion of acid-base equivalents to their inputs

2) Regulation of weak acids to conjugate bases in buffer systems

Question 9

The lungs will excrete what

Answer 9

CO2, a volatile acid

Question 10

Kidneys will excrete what

Answer 10

They will excrete acid, RNAE (renal net acid excretion) equal to NEAP (net endogenous acid production), which reflects dietary intake, cellular metabolism, and loss of acid and alkali from the body

Question 11

pH of blood is normally

Answer 11

7.4

Question 12

Intracellular pH is approximately

Answer 12

7.2

Question 13

The normal pH for arterial plasma ranges from

Answer 13

7.35-7.45

Question 14

What is the range for acidemia

Answer 14

If the pH < 7.35, so concentration of H+ is increasing

Question 15

What is the range for alkalemia

Answer 15

pH > 7.45, so H concentration is decreasing

Question 16

Why is CO2 a volatile acid

Answer 16

It has the potential to form H+ upon hydration, but it itself is not an acid

Question 17

CO2 to HCO3 equation

Answer 17

CO2 + H2O H2CO3 H+ + HCO3-

This is done by carbonic anhydrase

Question 18

The cycle of CO2 in the body

Answer 18

CO2 leaves the cells, enter the venous supply in RBCs, where it is converted to H+ and HCO3-. It is carried to the lungs where it is converted back to CO2 and expired

Question 19

Catabolism of proteins and phospholipids produces ______

Answer 19

50 mM/day of fixed acid

Question 20

Sulfuric acids

Answer 20

Produced from proteins with the sulfure-containing amino acids when metabolized

Question 21

Phosphoric acid is produced from

Answer 21

Phospholipids

Question 22

A buffer is what

Answer 22

A mixture of a weak acid and its conjugate base or a weak base and its conjugate acid

A buffered solution resists a change in pH

Question 23

Bronsted-Lowry equilibrium equation

Answer 23

HA + B A- + HB+

Question 24

What is pKa

Answer 24

When the rates of the forward and reverse reactions are equal, there is chemical equilibrium, so there is no net change in concentration of HA or A=

Question 25

What is the Henderson-Hasselbalch equation

Answer 25

pH = pKa + log ([A-]/[HA])

HA is CO2, pKa is of the buffer, A- is what is in the kidneys while HA is what is in the lungs

Question 26

When pH = pKa, what happens

Answer 26

The world explodes

Nah, there are equal concentrations of HA and A-

Question 27

A buffer is most effective when

Answer 27

Its pKa = environmental pH

Question 28

Strong acids have what type of pKa and K

Answer 28

High K and low pKa

Question 29

Weak acids, like H2CO3, have what kind of pKa and K

Answer 29

Low K and high pKa

Question 30

What are the two key buffer systems in the ECF

Answer 30

Bicarbonate (pKa = 6.1)

Phosphate (pKa = 6.8)

Question 31

What is the most important extracellular buffer

Answer 31

HCO3-/CO2

Question 32

What must you do to CO2 before using it to calculate pH

Answer 32

PCO2 must be converted to CO2 concentration by multiplying by the solubility of CO2 in blood, which is 0.03 mmol/L per mmHg

Question 33

For Bicarb, what is the pKa, values of A- in the kidneys, and values of HA in the lungs (PCO2)

Answer 33

pKa is 6.1
HCO3 in the kidneys is 24 mM
PCO2 in the lungs is 40 mmHg

Question 34

Why is bicarb a better buffer than phosphate

Answer 34

2 reasons

1) HCO3- is much higher concentration than phosphate
2) The acid from of the bicarb buffer is volatile CO2 and can be expired by the lugns

Question 35

The most significant intracellular buffer is what

Answer 35

Hemoglobin