Question

unit 1.1 biomolecules & cells test review
find the monomer of the following molecules:
enzyme
triglycerides
starch
glycogen
dna
true or false: changing one nucleotide in a dna molecule can change the function of the entire molecule.
label the parts of the nucleotide (5 - carbon sugar, phosphate, nitrogen base)
what is the property of lipids that makes it a good membrane for cells?
what is the purpose of an enzyme in a chemical reaction?
what conditions affect an enzymes ability to function at optimal potential?
1.
2.
3.
using the picture to the right, explain how an enzyme works.

Explanation:

1. Monomers:

• Enzymes are proteins, and their monomers are amino - acids.
• Triglycerides are made of glycerol and fatty acids.
• Starch is a polysaccharide, and its monomer is glucose.
• Glycogen is also a polysaccharide with glucose as the monomer.
• DNA is a nucleic acid, and its monomer is a nucleotide.

1. DNA statement: True. Changing one nucleotide can change the genetic code, thus altering the function of the entire molecule.
2. Nucleotide parts: A is the 5 - carbon sugar, B is the phosphate group, C is the nitrogen - base.
3. Lipids for cell membranes: Lipids are amphipathic (hydrophilic head and hydrophobic tail), which allows them to form a bilayer that is selectively permeable.
4. Enzyme purpose: Enzymes lower the activation energy of a chemical reaction, thereby increasing the reaction rate.
5. Enzyme - affecting conditions: Temperature, pH, and substrate concentration can affect an enzyme's ability to function optimally.
6. Enzyme action: The enzyme has an active site that is complementary in shape to the substrate. The substrate binds to the active site, forming an enzyme - substrate complex. The reaction occurs, and the products are released from the active site.

Answer:

1. Enzymes: Amino - acids; Triglycerides: Glycerol and fatty acids; Starch: Glucose; Glycogen: Glucose; DNA: Nucleotide
2. True
3. A: 5 - carbon sugar; B: Phosphate group; C: Nitrogen - base
4. Amphipathic nature
5. Lower activation energy
6. Temperature, pH, Substrate concentration
7. The enzyme has an active site complementary to the substrate. Substrate binds, reaction occurs, products are released.