Macromolecules and Monomers Quiz

Polymers and Macromolecules

• A polymer is composed of large molecules called macromolecules, which are multiples of simpler chemical units called monomers.
• Carbohydrates, lipids, proteins, and nucleic acids are macromolecules.
• Monomers are atoms or small molecules that bond together to form more complex structures such as polymers.

Monomers

• There are four main types of monomers: sugars, amino acids, fatty acids, and nucleotides.
• Carbohydrates, proteins, and nucleic acids are referred to as polymers because they are constructed by linking a large number of the same subunit, called a monomer.
• Lipids are not polymers because they contain two different types of subunits, glycerol and fatty acids.

Carbohydrates

• Most carbohydrates have a carbon-hydrogen-oxygen ratio of 1:2:1 (CH2O).
• Monosaccharides are single molecules of sugar, also known as simple sugars.
• A monosaccharide can have a backbone of carbon of 3-7 carbons.
• Glucose is a hexose sugar, with the formula C6H12O6.
• Disaccharides are two monosaccharides, such as maltose, sucrose, and lactose.

Polysaccharides

• Polysaccharides are long polymers like starch, glycogen, and cellulose that contain long chains of subunits.
• Also known as complex carbohydrates.
• Starch and glycogen are storage forms of glucose in plants and animals, respectively.
• Cellulose is found in plant cell walls and has a different linkage pattern, making it indigestible.
• Chitin is a structural polysaccharide found in the skeleton of crabs and similar animals.

Lipids

• Lipids are hydrophobic molecules that are insoluble in water.
• Triglycerides (fats and oils) are used as long-term energy storage for animals and plants.
• Phospholipids form membranes that separate environments and form inner compartments.
• Steroids are sex hormones, and wax serves as protection and prevents water loss.

Fats and Oils

• Triglycerides are made of a single glycerol unit and three fatty acid molecules.
• Fats are solid at room temperature, while oils are liquid at room temperature.
• Fatty acids are hydrocarbon chains that end with an acidic group “-COOH”, and contain 16 or 18 carbon atoms.
• Fatty acids can be saturated or unsaturated, with saturated having no double bonds and unsaturated having double bonds.

Phospholipids

• Lipids that have a phosphate group.
• Primary components of cellular membranes.

Steroids

• Have a backbone of four fused carbon rings.
• Cholesterol is a steroid that enters the body through our diet.
• Cholesterol is a precursor for other steroids like bile salts, estrogen, and testosterone.