Macromolecules Overview

Macromolecules

• Macromolecules are large organic molecules containing carbon, that make up all living things
• They include: carbohydrates, lipids, proteins, and nucleic acids
• Essential for life, as they run bodily functions, provide energy, and hold the instructions for bodily functions
• Everything learned in the rest of the semester relates back to macromolecules.
• Structurally, most macromolecules are polymers made of monomers

Structure Overview

• Monomers are small, basic sub-units (like a brick or a word)
• Polymers are larger, more complex structures made of monomers (like a brick wall or a sentence)

Making Polymers

• Dehydration reaction links monomers together to build a polymer.
• The reaction removes a water molecule.
• Example: When the body has excess glucose, it combines glucose molecules to build glycogen for storage

Breaking Polymers

• Hydrolysis breaks down polymers into individual monomers
• Water is added, breaking the bonds between monomers
• Example: In digestion, enzymes break down complex starches into simpler sugars

Carbohydrates

• Main Function: Short-term energy storage
• Other Uses: Structure, transport, signaling
• Found In: Sugars and starches (e.g., glucose, fructose, sucrose, starches)
• Composition: C, H, O
• Monomer: Monosaccharides (single sugars)
  • Examples: Glucose, galactose, fructose
• Polymer: Polysaccharides (larger sugar molecules)
  • Examples: Starch, glycogen, cellulose
• Energy Storage: 4 calories/gram

Lipids

• Main Function: Long-term energy storage
• Other Uses: Insulation, protection, structure (e.g., cell membranes)
• Found In: Fats, oils, phospholipids, steroids
• Composition: C, H, O
• Monomer: Fatty acids
• Polymer: Triglycerides
• Energy Storage: 9 calories/gram

Phospholipids

• A special type of lipid
• Structure: 2 fatty acids + 1 phosphate group
• Hydrophilic (water-loving) head (phosphate group)
• Hydrophobic (water-hating) tails (fatty acids)
• Phospholipid Bilayer: Forms the plasma membrane of cells
  • Makes the membrane selectively permeable

Proteins

• Main Function: Very diverse roles, runs the body (e.g., enzymes, hormones, structure, transport, movement, immune response, receptors, energy source)
• Found in: Meats, nuts, dairy; also made by the body
• Composition: C, H, O, N, P, S
• Monomer: Amino acids
• Polymer: Polypeptide (amino acids linked by peptide bonds)
• Energy Storage: 4 calories/gram
  • Proteins are often a last resort for energy.

Proteins (Folding)

• The protein's form dictates its function (e.g., enzymes)
• The shape of the protein determines what it does
• Proteins involve primary, secondary, tertiary, and quaternary structures.

Nucleic Acids

• Main Function: Store, transmit, and express genetic information (instructions for making proteins)
• Found in: DNA and RNA
• Composition: C, H, O, N, P
• Monomer: Nucleotides (e.g., adenine, guanine, cytosine, thymine, uracil)
• Polymer: Nucleic acid (DNA or RNA)
• Nucleic acids contain the instructions for making proteins
• Energy Storage: 0 calories/gram. They are not broken down for energy.

This quiz covers the essential concepts of macromolecules, including their structure, types, and functions in living organisms. Learn about the roles of carbohydrates, lipids, proteins, and nucleic acids, as well as the processes of polymer formation and breakdown. You'll gain a foundational understanding of how these large organic molecules contribute to life.