Question

1. What is NOT a function for lipids?

A. Make up the main structural component of cell membranes

B. Provide insulation in the body

C. Used to synthesis steroids, some vitamins and bile salts

D. Essential as biological buffers

E. Present as prostaglandins and other eicosanoids

2. If the Na+ concentration intracellularly (inside the red blood cell) is 0.9% and the Na+ concentration in the intravenous solution is 2.0%, what will happen to the red blood cells?

A.	They will swell and burst

B.	They will remain unchanged

C.	They will shrink as the Na+ ions leave the blood cells

D.	They will shrink from loss of water

3. In the human body, which can be moved by primary active transport? (3 points)

A.	Sodium (Na+) ions

B.

ATP

C.	Oxygen (O2)

D.	Amino acids

Please show the explanation.

Answer 1

D.Buffer are the substance which resist the change in pH on addition of small amount of base or acid.

The effects of biological buffers on lipids have not been fully investigated because of the long-standing assumption that these buffers are too hydrophilic to substantially interact with the lipid membrane.

2.

As the concentration inside Red blood cell is less it means it is having more water (solvent) remains in it compared to adjacent vein. Hence water will follow its concentration gradient and will flow from higher water concentration to lower water concentration Resulting shrinkage of RBC due to loss of water

3

Active transport require special carrier protein supplemented by expenditure of energy to move substance against the concentration gradient

Substance which can be moved are

Sodium Ions

Amino acids