Bio lab quiz 4

Macromolecules

Polymers found in living organisms that contain 5 or more carbon atoms in either ring or chain formation

What are the 4 polymers?

Lipids, carbohydrates, proteins, nucleic acids

What is an indicator?

Chemicals that change color in the presence of a specific organic substance

What indicates a positive result?

A color change

What indicates a negative result?

If a color doesn’t change showing that a macromolecule isn’t present

What is a nucleotide?

A monomer of nucleic acids

What is the structure of a nucleotide?

5-carbon sugar, a nitrogenous base (A,T,U,G,C), and atleast one phosphate group

What does a Lugol’s iodine test?

A carbohydrate test that indicates the presence of starch

What indicates there is starch present?

If the Lugol’s iodine color changes from yellow-orange to blue-black

What are the monomers for proteins?

Amino acids

What is the bond between amino acids?

Peptide bonds

How do you test the presence of proteins and short peptides?

The Biuret test

What indicates a positive result in Biuret test?

Violet or purple color

Do free amino acids have peptide bonds?

No because they are a single amino acid

What are the monomers for lipids?

Fatty acids, phospholipids, steroids

Are lipids nonpolar (hydrophobic)?

Yes

What is a polymer of fatty acids?

Triglycerides or fats

What is used to test lipids in a product?

Sudan III (hydrophobic)

What indicates a positive result in a Sudan III?

Orange color change

What indicates a negative result in a Sudan III?

No color change or brownish color

What is the function for lipids?

Long-term energy source and building cell structures such as plasma membrane

What is the function for carbohydrates?

Immediate energy source and structural components in cells.

What is the function for nucleic acids?

Storage and transmission of genetic information, as well as coding for proteins.

What is the function for proteins?

Catalyzing biochemical reactions, providing structure, and regulating processes within cells.

What is the monomer for carbohydrates?

Monosaccharides, such as glucose.

What do we use to detect the presence of reducing sugars?

Benedict’s solution (carbohydrates)

What indicates a positive result in the benedict’s solution?

A color change, usually to red or orange, indicating the presence of reducing sugars.

What is the bond called for nucleotides?

Phosphodiester bond

How do you bond fatty acids?

By forming ester bonds with glycerol.

How do you bond monosaccharides?

By forming glycosidic bonds.