3.2 and 3.3 Study Guide

Question 1

The monomer and polymer names for each macromolecule group.

Answer 1

• Carbohydrates
  Monomer=Monosaccharides Polymer=Polysaccharides
  -Lipids
  Monomer=Fatty Acids
  Polymer=Triglycerides
• Proteins
  Monomer=Amino Acids Polymer=Polypeptides
  -Nucleic Acids
  Monomer=Nucleotides Polymer=Polynucleotides

Question 2

The functions of each macromolecule group

Answer 2

Proteins – Molecular Machines.
Nucleic Acids – Information Repositories.
Lipids – Waterproof Membranes.
Carbohydrates – Stored Energy.

Question 3

Similarities and differences in amino acid structure

Answer 3

Each amino acid is structured from an amino group and a carboxyl group bound to a tetrahedral carbon. This carbon is designated as the α-carbon (alpha-carbon). Amino acids differ from each other with respect to their side chains, which are referred to as R groups.

Question 4

The four levels of protein structure

Answer 4

Primary, secondary, tertiary, and quaternary structure.

Question 5

What happens during protein denaturation

Answer 5

During the denaturation of proteins, the secondary and tertiary structures get destroyed and only the primary structure is retained.

Question 6

Explain how tertiary structure is formed by interactions between the following:
- Hydrophobic interactions
- Hydrophilic interactions
- Acidic and Basic side chains
- Cysteine side chains

Answer 6

Hydrophobic - nonpolar amino acid side chains (hydrophobic residues) cluster together in the interior of the protein, minimizing their contact with water, while hydrophilic amino acids remain on the protein’s surface interacting with the aqueous environment

Hydrophilic - amino acids tend to face the aqueous environment on the protein’s exterior

Acidic and Basic side chains - the negatively charged side chain of an acidic amino acid (like aspartic acid or glutamic acid) forms an ionic bond with the positively charged side chain of a basic amino acid (like lysine, arginine, or histidine), causing the protein chain to fold and bend into its three-dimensional shape

Cysteine side chains - through the creation of disulfide bonds, which are covalent linkages between the sulfur atoms of two cysteine residues brought close together during protein folding.

Question 7

Examples of protein types and functions: i.e. enzymes catalyze chemical reactions

Answer 7

Hemoglobin - Transport
Actin, tubulin, keratin - Structure
Insulin, glucagon - Hormone signaling

Question 8

Compare and contrast the structure and functions of different groups of macromolecules.

Answer 8

Nucleic acids: Stores and transfers info. Carbohydrates; Store energy, provide fuel, and build structure in body, main source of energy, structure of plant cell wall. Lipid: Insulator and stores fat and energy. Protein: Provide structural support,transport, enzymes, movement, defense. All contain carbon, hydrogen, and oxygen. All are organic compounds.

Question 9

Why and how would the structure and function of a protein change if a hydrophobic amino acid was substituted for a hydrophilic one?

Answer 9

A change from a hydrophobic to hydrophilic amino acid could disrupt interactions, leading to a change in the protein’s overall structure. A protein’s structure and function are closely linked, so changes in structure due to a single amino acid substitution can affect the protein’s function.