Biology Macromolecules and Organic Chemistry: Key Concepts and Structures

What is a molecule?

Atoms of the same element joined by chemical bonds.

What is a compound?

Atoms of different elements joined together (e.g., H₂O, CO₂).

What makes a compound organic?

It contains carbon.

What are macromolecules?

Large organic molecules made of polymers.

What is a polymer?

A long chain of repeating monomers.

What is a monomer?

A small molecule that joins to form polymers.

What are the four biological macromolecules?

Carbohydrates, lipids, proteins, nucleic acids.

What is the monomer of carbohydrates?

Monosaccharides (glucose, fructose, galactose).

What is the main function of carbohydrates?

Quick energy.

How do animals store carbohydrate energy?

Glycogen in the liver.

How do plants store carbohydrate energy?

Starch in roots.

What carbohydrate provides structure in plants?

Cellulose.

What carbohydrate provides structure in fungi?

Chitin.

What are lipids made of?

Glycerol + 3 fatty acids (fats), or phosphate group + 2 fatty acids (phospholipids).

Are lipids polymers?

No, they have no monomers.

What are the functions of lipids?

Long‑term energy storage, cell membranes, waterproofing, hormones.

What are examples of lipids with fatty acids?

Waxes, fats/oils, phospholipids.

What are examples of lipids without fatty acids?

Steroids.

What is the monomer of proteins?

Amino acids.

Where are proteins assembled?

Ribosomes.

What elements do proteins contain?

Carbon, hydrogen, oxygen, nitrogen, sometimes sulfur.

What are the functions of proteins?

Enzymes (speed reactions), hormones (regulate processes), structural (bones/muscles), transport (hemoglobin, membrane proteins), defense (antibodies).

What is the monomer of nucleic acids?

Nucleotide (phosphate group + sugar + nitrogenous base).

What elements do nucleic acids contain?

Carbon, hydrogen, oxygen, nitrogen, phosphorus.

What are the functions of nucleic acids?

Store genetic info (DNA), transmit hereditary info, transfer info nucleus → cytoplasm (RNA).

What are the bases in DNA?

Adenine‑Thymine, Cytosine‑Guanine.

What are the bases in RNA?

Adenine‑Uracil, Cytosine‑Guanine.

What are enzymes?

Hydrophilic globular proteins that act as biological catalysts.

What do enzymes do?

Lower activation energy and speed up chemical reactions without being consumed.

Why are enzymes important?

Essential for digestion and metabolism.

Macromolecule

A quite large organic molecule

Carbohydrates

These macromolecules are comprised of hydrogen, oxygen and carbon molecules with the typical equal numbers of carbon and oxygen atoms and twice that number of hydrogen atoms.

Monosaccharides

A type of carbohydrate

Disaccharides

A type of carbohydrate

Polysaccharides

A type of carbohydrate

Ribonucleic acid (RNA) and Deoxyribonucleic acid (DNA)

Nucleic acids that are formed with the union of nucleotide monomers

Lipids

Also referred to as fats, are macromolecules that are mostly comprised of carbon and hydrogen and are formed with the union of fatty acid and glycerol monomers.

Adipose tissue

Fat tissue that is a type of a lipid

Fats

A type of a lipid

Oils

A type of a lipid

Phospholipids

A type of a lipid

Waxes

A type of a lipid

Steroids

A type of a lipid

Proteins

Also referred to as polypeptides, these macromolecules of polymers are formed with the union of amino acid monomers held together with peptide bonds.

Hydrophilic globular protein macromolecules

These macromolecules can dissolve in water

Hydrophobic fibrous macromolecules

These macromolecules are not soluble in water.

Enzymes

Biological catalysts that speed up the chemical reactions in the body but they are not altered or changed as a result of these reactions.

Dehydration synthesis

This process, also referred to as dehydration and condensation synthesis, is the process of removing water so that polymers can be bound together to form macromolecules.

Hydrolysis

The addition of water to a macromolecule that is the opposite process of dehydration synthesis. Hydrolysis breaks the polymers' bonds and releases energy and single monomers.

Nucleic acids

Ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) that are formed with the union of nucleotide monomers

RNA, or ribonucleic acid

The nucleic acid that is a single helix strand macromolecule that consists of adenine, cytosine, guanine and uracil

DNA or deoxyribonucleic acid

The nucleic acid that is a double helix macromolecule with the foundation as thymine

Molecule

A collection of a group of one or more atoms with the same and identical element that are joined to each other with chemical bonds as based on the valence electrons of each of the atoms.

Compound

A collection of a group of one or more atoms with different elements that are joined to each other with chemical bonds as based on the valence electrons of each of the atoms.