Fluid & Acid Balance

Question 1

Is most body fluid in the ICF or ECF?

Question 2

What are the main ions in the ECF?

Question 3

What are the main ions in the ICF?

Question 4

What two long-term control measures are used to maintain blood pressure in the face of
changes in ECF volume?

Question 5

Why does control of salt load go along with control of fluid volume?

Question 6

What are the two mechanisms by which the body regulates salt load?

Question 7

What does hypertonicity and
hypotonicity do to cells?

Question 7

When water is lost but not solutes, does this lead to hypertonicity or hypotonicity? How
about if water is gained without solutes being gained?

Question 8

What is metabolic H2O?

Question 9

What is insensible loss of H2O?

Question 10

What do hypothalamic osmoreceptors respond to? What triggers them? What does their
activity lead to? Through what mechanism?

Question 11

Does an acid have a low or high pH? How about a base?

Question 12

What is the pH of H2O? What
is the pH of body fluids? How much deviation of pH can we tolerate?

Question 13

What does it mean that an acid is “strong” or “weak”? How does this relate to its
dissociation constant?

Question 14

What are the three main sources of H+ in the body? Which of these is the largest
source?

Question 15

What is acidosis and alkalosis?

Question 16

What is the difference between respiratory acidosis and
metabolic acidosis?

Question 17

What are the three body defenses against changes in pH?

Question 18

What does a chemical buffer system do? How does bicarbonate act as a chemical
buffer? How fast do buffers act? What are other buffers in the body?

Question 19

Under a normal functioning respiratory system, does [H+] continually increase? Why or
why not?

Question 20

In metabolic acidosis or alkalosis, how does regulation of ventilation bring the pH back
to normal? How long does this take to kick in?

Question 21

Is all filtered HCO3- excreted or reaborbed? How does H+ secretion play a role in this?

Question 22

Is more or less H+ secreted than HCO3- filtered into the filtrate?

Question 23

Secretion of H+ into the tubule is coupled with what?

Question 24

What are the two buffers in the urine that help bring up the pH of urine?

Question 25

During acidosis, what happens to H+ and HCO3- in the kidneys? How about during
alkalosis? How do these things change normalize pH?

Question 26

How long does it take renal regulation of pH to kick in?