[BIOCHEM LAB] MIDTERMS TO1

55%

What percentage of the cell membrane is composed of protein?

25%

What percentage of the cell membrane is composed of phospholipids?

13%

What percentage of the cell membrane is composed of cholesterol?

3%

What percentage of the cell membrane is composed of carbohydrates?

4%

What percentage of the cell membrane is composed of other forms of lipids?

Cell Membrane

What is the outermost layer of the cell?

Diffusion

What is the net transport of molecules from a region of higher concentration to one of lower concentration by random molecular motion?

Equilibrium

What is it called when molecules are even throughout a space?

Diffusion Rate

What is measured by the number of diffusing molecules passing through the membrane per unit time?

Dialysis

What is the method of separating particles of different dimensions in a liquid mixture using a thin semi-permeable membrane?

Hypotonic Solution

What type of solution causes water to enter the cell?

Isotonic Solution (equal solute concentration, no net water movement)

What type of solution results in no net water movement?

Hypertonic Solution

What type of solution causes water to leave the cell?

Osmosis

What is the movement of water across a semi-permeable membrane?

dissolution, through, loosening

meaning of dialusis, dia, and lusis

yellow ring

What makes a Heller's Test positive?

NO presence of reducing sugars indicated by a brick-red precipitate

Why is Fehling's Test negative in the experiment?

presence of ions/salts indicated by a white precipitate

Why is the test for salts positive in the experiment?

increases rate due to higher kinetic energy

How does increasing temperature affect the rate of diffusion?

INCREASES

What happens to the solution level when osmosis occurs?

CONTRACTILE VACUOLES

What organelles in animal cells may be in danger of bursting so they will pump water out of the cell