Lecture 7 - Water, Ions And Cell/tissue Fluid Balance

Question 1

What is osmosis?

Answer 1

The movement of a solvent across a semi permeable membrane toward a higher concentration of solute. When a cell is submerged in water, the water molecules pass through the cell membrane from an area of low solute concentration to high solute concentration

Question 2

High to low concentrations is called?

Answer 2

Diffusion

Question 3

Where is intracellular fluid located?

Answer 3

Inside the cell

Question 4

Where is extra cellular fluid located?

Answer 4

Outside the cell

Question 5

What is inside of fluid?

Answer 5

Ions, solutes and water

Question 6

Water can be lost though what four things?

Answer 6

1. Water vapor
2. Lost in feces
3. Sweat glands
4. Urine

Question 7

Isotonic means?

Answer 7

The ECF and ICF are in balance, with the two solutions isotonic

Question 8

What happens if we lose water from the ECF?

Answer 8

Water loss from the ECF decreases volume and makes this solution hypertonic with respect to the ICF. The water moves from low concentrations of solutes to restore osmotic equilibrium

Question 9

If the volume of ICF decreases what happens to the volume of ECF?

Answer 9

Decreased ICF volume = increased ECF volume - that cell is now going to shrink

Question 10

ICF is larger in size and has a greater volume of water. What happens if we have a reduction of ICF?

Answer 10

If the volume of ICF is constantly reducing, it’ll try and balance that by moving water across. This can cause dehydration and in this process the cell will shrink

Question 11

What happens to our cells if we have too much water?

Answer 11

If we have too much water, the volume of the ECF will increase. A lot of dilution of those solutes because there is more water for a given concentration. It will flow from the ECF to the ICF and the if the ICF volume increases, the inside of the cell will expand and be too plump

Question 12

What happens when electrolytes hit the blood?

Answer 12

The electrolytes will dissociate and release ions

Question 13

What is hypertonic solution?

Answer 13

A lot of water in the solution

Question 14

What is hypertonic?

Answer 14

A lot of solute molecules in the solution?

Question 15

Which ions do electrolytes dissociate and release when hitting the blood?

Answer 15

Sodium, potassium and calcium

Question 16

Which tissues have excitable membrane potential?

Answer 16

Neurons and muscle tissue

Question 17

Which cells have a membrane potential but are not excitable?

Answer 17

Epithelial cells

Question 18

Both cations and anions are present inside and outside of cells. True or false?

Answer 18

True

Question 19

What is resting membrane potential?

Answer 19

The distribution of ions creating the electricity

Question 20

What are the levels of sodium and potassium outside the cell in ECF?

Answer 20

Sodium = high 
Potassium = low

Question 21

What levels are sodium and potassium inside the cell in ICF?

Answer 21

Sodium = low 
Potassium = high

Question 22

Plasma membrane has a lipid bilayer preventing the free flow of ions. What does this lipid bilayer do?

Answer 22

They can channel these ions through cations to maintain membrane potential or use an active transport potential. Passive flow = high to low

Question 23

Why is the lipid bilayer flow passive?

Answer 23

It is passive as it relies on ATP, an energy molecule. Resting membrane is dependent on the chemical gradients from the active ATP process