Homeostasis

Question 1

Isovolaemia

Answer 1

THE CONSTANCY OF THE VOLUME OF ECF

Question 2

Dehydration

Answer 2

decreased volume of ECF = less than than 20%

no drinking water, diarrhea, vomiting, increased sweating, etc

Question 3

Overhydration

Answer 3

increased volume of ECF = more than than 20%

renal diseases, too much drinking, too much infusion, etc

Question 4

Hypovolaemia

Answer 4

decreased volume of blood plasma

bleeding, shock, etc

Question 5

Hypervolaemia

Answer 5

increased volume of blood plasma

cardiac, renal diseases, etc

Question 6

Oedema

Answer 6

increased volume of ISF

cardiac decompensation, hepatic, renal diseases, starvation, allergic processes, inflammation, etc

Question 7

Isosmosis

Answer 7

THE CONSTANCY OF THE OSMOTIC PRESSURE (the force which prevents the osmotic movement) OF ECF

Question 8

Hypertonic solution

Answer 8

E.g. 3% NaCl - RBC shrinks

Question 9

Isotonic solution

Answer 9

0.9% NaCl - Shape of RBC does not change

Question 10

Hypotonic solution

Answer 10

0.3% NaCl - RBC disrupts (hemolysis)

Question 11

Isohydria

Answer 11

THE CONSTANCY OF THE pH OF ECF

Question 12

pH of ECF

Answer 12

7.4

Question 13

Acidosis/alkalosis

Answer 13

Between 7.35 and 7.0 = acidosis

Between 7.45 and 7.8 = alkalosis

Question 14

Buffer system in ECF

Answer 14

BICARBONATE BUFFER SYSTEM:

• carbonic acid (H2CO3) and sodium bicarbonate (NaHCO3)
• pKa=6.1

Question 15

Buffer system in ICF

Answer 15

PHOSPHATE BUFFER SYSTEM:
-dihydrogen phosphate - H2PO4- and monohydrogen phosphate - HPO42-
-pKa =6.8
HEMOGLOBIN BUFFER SYSTEM:
-has several buffering groups per molecule (e.g. imidazole)
-different pKa values (6.5-7.8)