Question

6. Under what conditions is water actively transported across a membrane?

            A. Only from high osmotic pressure to low osmotic pressure

            B. Only from low osmotic pressure to high osmotic pressure

            C. Only mammals have evolved the capacity for active transport of water in the kidney

            D. Many vertebrates have aquaporins that can actively transport water

            E. None - water always moves by passive transport

7. You are studying two animals from the central Atlantic Ocean, a cnidarian and a mollusc, and you know that both are strict osmoconformers. Without knowing anything else about the animals, what can you assume?

            A. Both organisms have the same [Mg²⁺] in their body fluids

            B. Neither organism can regulate its ionic composition

            C. Both organisms can tolerate the same range of salinities

            D. Neither organism has a sodium-potassium ATPase

            E. Body fluids from both organisms have the same osmolarity

8. If an animal produces urine with an osmotic U/P ratio of 3, then…

            A. The animal is preferentially excreting water

            B. The animal is preferentially retaining solutes

            C. The animal could be a freshwater teleost or amphibian

            D. The animal could be a marine teleost

            E. The animal could be a mammal

9. The cytoplasm of a mammalian red blood cell is…

            A. Isosmotic to a 75 mM NaCl solution

            B. Hyposmotic to a 100 mM NaCl solution

            C. Hyperosmotic to a 300 mM glycerol solution

            D. Isosmotic to a 300 mM triacetin solution

            E. Hyposmotic to a 300 mM ethylene glycol solution

10. Metabolic water refers to…

            A. Water produced from the oxidation of foodstuffs

            B. Water consumed in the oxidation of foodstuffs

            C. Water lost from the integument and respiratory surfaces during intense metabolic activity

            D. Water lost from respiratory surfaces at a rate proportional to metabolic rate

            E. Water required to dissolve dry foodstuffs so they are available for metabolism

Answer 1

Answer 6: from low osmotic pressure to high osmotic pressure

Osmosis : movement of water molecule from its high concentration to its low concentration upto the equilibrium.

Answer 10: water produced from the oxidation of food stuff.

In the process of metabolism, water is produced as byproduct.