Week 8- Acids/Bases

Question 2

Bicarbonate ion (HCO3-) is lost from

Answer 2

GI tract and in urine

Question 3

Recovery of New Bicarbonate of Secretion of Ammonium

Answer 3

• metabolism of glutamine in renal tubule cells produces ammonium ions
• Glutamine = 2 NH4+ +. 2 HCO3-
• Ammonium ions are actively secreted via Na+/NH4+ counter-transporter
• NH4+ is then excreted and newly formed bicarbonate is reabsorbed

Question 4

the respiratory system regulates acid-base homeostasis by

Answer 4

altering the rate and depth of ventilation

Question 5

Elimination of CO2 is faster than it is produced

Answer 5

Respiratory Alkalosis

Question 6

Common cause of respiratory alkalosis

Answer 6

hyperventilation, may occur with anxiety, fever, sepsis, or strenuous exercise

Question 7

Decreased pH = increased H+

Answer 7

acidosis

Question 8

Renal compensation involves invoking renal mechanisms discussed to ______

Answer 8

retain or eliminate bicarbonate as appropriate

Question 9

Increasing ventilation will ______ CO2 from the body, thus reduce acid

Answer 9

remove

Question 10

Decreasing ventilation will _____ CO2 that can form H+ and increase acid

Answer 10

retain

Question 11

Increased pH = decreased H+

Answer 11

alkalosis

Question 12

2 other examples of buffers

Answer 12

phosphate (effective in urine and intracellular fluid) Proteins such as hemoglobin

Question 13

the renal system regulates acid- base homeostasis by

Answer 13

altering bicarbonate reabsorption, generating new bicarbonate, or by secreting bicarbonate

Question 14

H+ lost in

Answer 14

vomitus or urine

Question 15

Metabolic acid-base disturbances are all imbalances NOT caused by _______

Answer 15

too much or too little CO2 in the blood

Question 16

acid and base homeostasis is largely regulated by

Answer 16

the respiratory and renal systems

Question 17

• Bicbarb levels in the blood are above or below normal rang of 22-26 mEq/L
• Second most common acid-base imbalance
• Blood pH and HCO3- levels are below normal

Answer 17

Metabolic Acidosis

Question 18

• Rising blood pH and HCO3-
• acid loss or bicarbonate ion retention are causes
• examples include vomiting (acid loss) and constipation (excess absorption of HCO3- by colon)

Answer 18

Metabolic Alkalosis

Question 19

Important extracellular fluid buffer

Answer 19

Bicarbonate

Question 20

Causes of Respiratory Acidosis

Answer 20

inadequate ventilation, pneumonia, cystic fibrosis, emphysema

Question 21

Bicarbonate reabsorption depends on _______

Answer 21

H+ secretion

Question 22

Molecules that release hydrogen ions (protons) in solution

Answer 22

Acids

Question 23

Occurs by failure of respiratory system to function

Answer 23

Respiratory acidosis or alkalosis

Question 24

Bicarbonate is reabsorbed using _______ in the renal tubule cells

Answer 24

carbonic anhydrase enzyme

Question 25

Causes of metabolic acidosis

Answer 25

• excess alcohol ingestion (forms acetic acid)
• loss of bicarbonate (persistent diarrhea)
• diabetic ketoacidosis

Question 26

Whats happening in respiratory acidosis

Answer 26

• CO2 accumulates in the blood
• Decreasing pH and increasing P_CO2 are characteristic

Question 27

Bicarbonate is freely filtered at the ______

Answer 27

glomerulus

Question 28

Molecules that can accept a hydrogen ion

Answer 28

Bases

Question 29

Most common type of acid-base imbalance

Answer 29

Respiratory acidosis

Question 30

How is a new Bicarbonate Ion generated

Answer 30

• Recovery of new bicarbonate by secretion of H+ occurs when all filtered bicarbonate has been reabsorbed
• Secreted H+ combines with non-bicarbonate buffer (HPO₄ ^2-)
• traps H+ in HPO₄ ^2- ion for excretion
• Net gain of new bicarbonate ion occurs