The Anatomy and Physiology of Animals/Diffusion and Osmosis Worksheet 2

Chapter 3 The Cell

1. Circle the correct answer.

a) When red blood cells are placed in an isotonic solution they:

swell / stay the same / shrink.

b) Red blood cells are isotonic to:

distilled water / 0.2% salt solution / 0.9% salt solution / 2.0% salt solution.

c) Red blood cells placed in a 2.0% salts solution would:

swell / stay the same / shrink.

d) Red blood cells placed in distilled water would:

swell / stay the same / shrink.

e) When red blood cells are placed in distilled water:

the water enters the cells / the water leaves the cells / the water does not move / the salts in the cells leave the cells

f) Red blood cells placed in a 0.9% salt solution would:

swell / stay the same / shrink.

g) Red blood cells placed in distilled water are in a:

hypertonic / isotonic / hypotonic solution.

h) Red blood cells placed in 0.9% salt solution are in a:

hypotonic / isotonic / hypertonic solution.

i) Red blood cells placed in a 2.0% salt solution are in a:

hypotonic / isotonic / hypertonic solution.

j) A dialysis bag (made of an artificial semi-permeable membrane) filled with 0.5% salt solution and placed in a beaker containing 3.0% salt solution will:

swell / stay the same / shrink.

2. Three bottles are filled with three different solutions. One with distilled water, one with 0.9% salt solution and the third with 9.0% salt solution. A few dried apricots are placed in the three bottles and left in the solutions for an hour.

The apricots in bottle A stay the same.

The apricots in bottle B shrink

The apricots in bottle C swell.

Now answer the following questions:

i) Which bottle contains the most concentrated salt solution? A B C

ii) Which bottle contains water? A B C

iii) Which bottle contains the isotonic salt solution? A B C

iv) Which bottle contains the hypotonic solution? A B C

v) Which bottle contains the hypertonic salt solution A B C

3. Now try this one!

A semi - permeable membrane (dialysis) bag, containing 4% salt, 4% glucose and 4% albumin is suspended in distilled water. Assume the bag is permeable to all substances except albumin.

Circle the correct answer in the statements below.

(Note that salt has quite a small molecule, glucose has a moderate sized molecule and albumin is a protein with a very large sized molecule.)

a) The salt: moves into the bag / moves out of the bag / does not move

b) The water: moves into the bag / moves out of the bag / does not move

c) The albumin: moves into the bag / moves out of the bag / does not move

d) The glucose : moves into the bag / moves out of the bag / does not move

e) The salt moves by: diffusion / osmosis / active transport / it does not move because the molecules are too large.

f) The water moves by: diffusion / osmosis / active transport / it does not move because the molecules are too large.

g) The albumin moves by: diffusion / osmosis / active transport / it does not move because the molecules are too large.

h) The glucose moves by: diffusion / osmosis / active transport / it does not move because the molecules are too large.

Worksheet 2 Answers