homeostasis and homeostatic integration

Question 1

define homeostasis

Answer 1

the tendency towards a stable equilibrium between interdependent elements, stabilised by physiological processes

Question 2

what are the parameters for homeostatic control?

Answer 2

• pH
• ion concentration
• water
• small molecules

Question 3

what is the pH and [Ca2+] in the cytosol?

Answer 3

pH 7.1

[Ca2+] 10-100nm

Question 4

what is the pH and [Ca2+] in the mitochondrial matrix?

Answer 4

pH 7.7

[Ca2+] 1mM

Question 5

what is the pH and [Ca2+] in the ECF?

Answer 5

pH 7.4

[Ca2+] 2mM

Question 6

what is the [Ca2+] in the endoplasmic reticulum?

Answer 6

1mM

Question 7

what is the pH range in the secretory vesicles?

Answer 7

5-6

Question 8

what is the pH range in the lysosomes/endosomes?

Answer 8

4.6-6

Question 9

what are the main differences between the ionic composition of the intracellular fluid and extracellular fluid?

Answer 9

intracellular fluid: low sodium, high potassium, low Cl, low HCO3 and really low Calcium
extracellular fluid: resembles seawater

Question 10

what is meant by epithelia and what is its role?

Answer 10

the interface between the internal environment of the body and the external space. its job is to maintain volume and composition of the extracellular fluid

Question 11

what is the equation for rate of solute movement?

Answer 11

J = P x (C1-C2)