Testing for Proteins

Exercise 1: Testing for Proteins

Purpose:

The purpose of this lab is to find a qualitative sample of four substances. Biochemical tests will be conducted in order to identify the presence of lipids, carbohydrates, and proteins. There will also be two tests conducted to identify two different types of protein that are present: starches and simple sugars. The lab relates to the subject of macromolecules that are essential to life. The testing for nucleic acids will not be performed in this lab.

Materials:

1 Egg, fresh raw

2 Coffee cups

1 Distilled water

1 Onion, small

1 Paper Towel

1 Pencil

1 Whisk or fork

1 Mixing bowl or blender jar

1 Sugar

1 Sauce pan or deep skillet

1 Clock or timer

1 Potato, small white

1 Vegetable oil

1 White Vinegar

1 Aluminum Foil - 6"x 6"

2 Cup, Plastic, 9 oz Short

1 Cylinder-50-mL - Graduated, Plastic

1Dissection-kit with 7-tools - Bent Probe, Dropping Pipet,

Probe, Ruler in pocket, Scalpel with 2 Blades -

Scissors, Tweezers

1 Goggles-Safety

1 Filter Paper 12.5-cm

1 IKI Indicator, 2.1% - 7 mL

1 Mortar and pestle, ceramic

1 Pencil, marking

1 Pipet, Long Thin Stem

1 Slide - Cover Glass - Cover Slip Cube

1 Slide-Box-BK-1 with Blank Slides

1 Sudan III - 2 mL in Glass Vial

Test Tube(6), 13 x 100 mm in Bubble Bag

1 Test-tube-clamp-holder

1 Test-tube-cleaning-brush

Test-tube-rack-6x13-mm

Pocket Microscope

1 Benedict's Reagent - 15 mL in Dropper Bottle

1 Biuret Reagent - 4 mL in Pipet

1 Glucose Solution in a Dropper Bottle

1 Pipet, Empty Long Stem - Labeled IKI Solution

1 Pepsin Powder - 0.1 gm in Dropper Bottle

1 Starch Solution, 1% Stabilized - 7 mL

Hypothesis:

If proteins are essential for growth and repair, then they must be present in the egg white and pepsin, but not in sugar and distilled