Securing Higher Grades Costing Your Pocket? Book Your Course help Tutor at The Lowest Price Now!

Get Instant Course Help

Osmosis and diffusion report sheet

  1. Osmosis

Experiment (dry lab)

There are 3 diagrams of animal cells (a, b, c) and 3 diagrams of plant cells (a, b, c) in solutions of varying tonicity. Label the diagrams as isotonic solution, hypertonic solution, or hypotonic solution.

Animal cells:

(a)

Hypotonic

(b)

Isotonic

(c)

Hypertonic

Plant cells:

(a)

Hypotonic

(b)

Isotonic

( c)

Hypertonic

  1. Effect of temperature and size

Observe the agar plate at 25°C, 30 min.

Experiment (dry lab)

Potassium permanganate at 25°C

Janus Green at 25°C

Time

Distance in mm

Time

Distance in mm

30 min

25

30 min

20

Potassium permanganate (294 Daltons) and Janus Green (511 Daltons) dyes

Which dye has greater diffusion, potassium permanganate or Janus Green?

Potassium Permanganate

Why?

The molecular weight of Potassium Permanganate is less so it diffuses quicker.

Observe the agar plate at 5°C, 30 min.

Experiment (dry lab)

Potassium permanganate at 5°C

Janus Green at 5°C

Time

Distance in mm

Time

Distance in mm

30 min

23

30 min

18

Potassium permanganate (294 Daltons) and Janus Green (511 Daltons) dyes

Which dye has greater diffusion potassium permanganate or Janus Green?

Potassium Permanganate

Why?

The molecular weight of Potassium Permanganate is less so it diffuses quicker.

Compare the agar plates at 5°C and 25°C.

Experiment (dry lab)

Which agar plate shows greater diffusion, 5°C or 25°C?

Potassium Permanganate

Why?

The molecular weight of Potassium Permanganate is less so it diffuses quicker.

Effect of temperature on diffusion of iodine

Experiment (at home lab)

QUESTIONS

Temperature of your cups:

169°C

25°C

Is the food coloring evenly distributed in each?

No

Explain.

Higher temperatures tend to increase rate of diffusion (which will distribute evenly)

  • Effect of solute concentration

Experiment (dry lab)

In the weight change column, record if the bag should increase in weight, decrease in weight, or stay about the same.

#

Bag contents

Beaker contents

Weight change
(bag increases, decreases or stays about the same)

Beaker contents
(isotonic, hypotonic or hypertonic solution)

1

10 ml Distilled water

200 ml Distilled water

Same

Hypertonic

2

10 ml 10% sucrose

200 ml Distilled water

Increase

Isotonic

3

10 ml 20% sucrose

200 ml Distilled water

Increase

Isotonic

4

10 ml 40% sucrose

200 ml Distilled water

Increase

Isotonic

5

10 ml Distilled water

200 ml 40% sucrose

Decrease

Hypotonic

Which bag should gain the most weight?

4

  1. Differential permeability of membranes

Experiment (dry lab)

Test for

Is test positive or negative?

Starch

Negative

Protein

Negative

Chloride ion

Positive

Sulfate ion

Positive

Which ones (starch, protein, chloride ions, sulfate ions) moved through the dialysis tubing and into the beaker?

Chloride ions and Sulfate Ions

Why did some not move from the bag into the beaker?

They were too big to pass through the membrane.

  1. Diffusion and osmosis in living cells

Experiment (dry lab)

  1. Osmosis with red blood cells

Describe the blood cells.

0.9% NaCl , Normal blood cells

Round shapes with something that looks like a nucleus in the middle

10% NaCl, Crenated cells

Shriveled almost popcorn looking

1. What solution causes cells to appear this way?

Isotonic, hypertonic or hypotonic solution.

2. What solution causes cells to appear this way?

Isotonic, hypertonic or hypotonic solution.

Hypertonic

Isotonic

    1. Osmosis with plant cells

Describe the plant cells.

0% NaCl, Turgid cells

Chloroplasts are pushed out to periphery of cell

20% NaCl, Plasmolyzed cells

Chloroplasts are pushed to center of cell

1. What solution causes cells to appear this way?

Hypertonic or hypotonic solution.

2. What solution causes cells to appear this way?

Hypertonic or hypotonic solution.

Hypotonic

Hypertonic

Diffusion in cucumber cells

Experiment (at home lab)

QUESTIONS

1. When comparing the firmness of the cucumber slices, how would you describe each, firm (turgid cells) or soft (plasmolyzed cells)?

Cup 1

Turgid Cells

Cup 2

Plasmolyzed Cell

Cup 3

Turgid Cell

2. What caused one to be firm and the other to be soft?

Explain.

The salt forced the water out of the cucumber cells causing them to become flaccid.

Want a fresh copy of this sample assignment
Course Help Features
Course Help Services
QR Code Course Help
elearningfeeds