Lab 3-Investigative Biochemistry

Question 1

Benedict’s reagent detects the presence of:

Normal color of reagent:

In the presence of ____________ and heat, it will turn:

Answer 1

Simple sugars (mono- and disaccharides)

Turquoise-blue

A brick orange color

Question 2

Iodine detects the presence of:

Normal color of this reagent is:

In the presence of a __________, it will turn:

Answer 2

Starch (a polysaccharide)

Amber-yellow

A blue-black color

Question 3

Biurets reagent detects the presence of:

Normal color of this reagent is:

In the presence of a _________, it will turn:

Answer 3

Protein

Blue

Pink-violet

Question 4

Sudan reagent detects the presence of:

The normal color of this reagent is:

This reagent is more soluble in ________ than in aqueous solutions.

Positive result is indicated by:

Answer 4

Lipids

Red

Lipids

Concentration of the due in the lipid layer

Question 5

Negative control

Answer 5

Water

Question 6

Positive control in Benedicts:

In iodine:

In Biuret/Bradford:

In Sudan:

Answer 6

Pure monosaccharides

Polysaccharide

Protein serum albumin

Mixture of oil and water

Question 7

Benedicts:

Iodine:

Biuret:

Sudan:

Answer 7

Glucose/sucrose

Corn starch

Serum albumin

Oil

Question 8

Hydrophobic stain

Answer 8

Sudan

Question 9

Which compound is most common in foods that come from plants?

Answer 9

Carbohydrates?

Question 10

Which compound is most common in foods that come from animals?

Answer 10

Proteins?

Question 11

4 kinds of basic building blocks

Answer 11

Carbohydrates
Proteins
Lipids
Nucleic acids