Catalyst: (Put this in the top margin above the first page of your lab)

Describe what a ‘sugar rush’ feels like in your body after you eat a lot of candy. Think about how your brain responds?

Heart? Stomach? Etc… Agenda Catalyst Pre-lab Questions Objective Follow simple experimental design to investigate how membranes affect the molecular movement.

Background

• Please read the background information on the first page of your lab.

• Annotate important information as you see appropriate.

In your lab….• You will make a model of a cell• Investigate the permeability if DYALYSIS TUBING to

starch. • Starch is a carbohydrate, carbohydrates are made

out of sugar• Write a one sentence purpose for the lab at the

bottom of pg. 2• Your lab group will decide if starch will go in the

internal environment of your ‘cell’ or get poured around external environment of your ‘cell’

• Identify the independent variable on pg. 2 (hint: What are you manipulating?)

Two options…

Starch

Water

Water

Starch

• The starch will either DIFFUSE through the membrane or it wont.

• We will use indicators to look for the presence of the starch

• Osmosis will also influence the mass of the cell so you will also measure the initial and final mass.

• Identify the dependent variable for this lab on pg. 2 (Hint: What are you measuring?)

With your lab group…. Pg. 2-5• Assign roles for the lab• Decide if starch will be in the interior or exterior

environment of your cell model • Write a hypothesis that starts “ If starch is in the

_________ environment, and the dialysis tubing is permeable to starch, then_____________________ because diffusion will________________________.

• Identify your control group • Identify your controlled variables • Complete part B ‘review of literature’ book pgs. 3-4

(PLEASE DO NOT DO GLUCOSE or BENIDICTS SOLUTION) (book pg. 162)

• Explain the concepts on pg. 5 (Book pgs. 222-224)