Biological Tests for Macromolecules

What color change indicates the presence of glucose in Benedict's Test?

Which solution is used to test for starch?

In the Biuret Test, what indicates the presence of protein?

What does a positive Emulsion Test reveal?

What is the first step in the Benedict's Test for glucose?

Which of the following tests requires a hot water bath?

What color does iodine change to when starch is present?

What is the function of ethanol in the Emulsion Test?

What is the expected color change in the Biuret Test if protein is detected?

Which test uses a solution that changes color from brown/yellow to blue-black?

What should be added to the food sample in the Emulsion Test to inspect for fat?

Which nutrient test requires heating in order to produce a valid result?

What does a result of a white, cloudy emulsion indicate in an Emulsion Test?

Testing for Glucose

Benedict's test is used to detect the presence of glucose.
The solution changes color from blue to green, yellow, orange, or brick-red depending on the concentration of glucose.

Testing for Starch

Iodine test is used to detect the presence of starch.
The iodine solution changes color from brown/yellow to blue-black.

Testing for Protein

Biuret test is used to detect the presence of protein.
The solution changes color from blue to purple.

Testing for Fat

The emulsion test is used to detect the presence of fat.
A white, cloudy emulsion (milky layer) indicates the presence of fat.

Benedict’s Test for Glucose

A blue solution of Benedict’s reagent turns to green, yellow, orange or brick-red in the presence of glucose.
The color change depends on the concentration of glucose in the sample.
A hot water bath is used to speed up the reaction.

Iodine Test for Starch

A brown iodine solution turns blue-black in the presence of starch.
The test can be performed in a test tube or on a spotting tile.

Biuret Test for Protein

A blue Biuret solution will turn purple in the presence of protein.
Biuret solution is a mixture of sodium hydroxide and copper sulfate.

Emulsion Test for Fat

A milky layer (emulsion) forms in the presence of fat.
Fat dissolves in ethanol.
Adding water to an ethanol solution with fat results in an emulsion.

This quiz covers the different tests used to detect macromolecules such as glucose, starch, protein, and fat. Each test's specific reaction and color change are highlighted, providing a comprehensive overview of biochemical testing methods. Test your knowledge on these essential laboratory techniques.