Macromolecules: Proteins and Nucleic Acids

Vocabulary flashcards covering the structure, function, elements, and key types of proteins, nucleic acids, carbohydrates, and lipids.

Organic vs Inorganic Compounds

Classification separating carbon-containing molecules like carbs, proteins, and fats (organic) from non-carbon or mineral substances like salts, water, and oxygen (inorganic).

Protein

A macromolecule composed of one or more chains of amino acids, containing carbon, hydrogen, oxygen, and nitrogen ($\text{CHON}$, sometimes $\text{S}$).

Amino Acid

The monomer unit of proteins, containing a central carbon, an amine group ($\text{NH}_2$ or $\text{NH}_3$), a carboxyl group ($\text{C=O}$, $\text{OH}$), a hydrogen atom, and a variable R-group.

R-Group

The variable side chain in an amino acid that determines its unique structure, chemical properties, and specific protein function.

Dipeptide

A molecule formed by joining two amino acids together through a peptide bond during a dehydration synthesis reaction.

Polypeptide

A polymer chain consisting of many amino acids linked together by peptide bonds.

Protein / Polypeptide Chemical Structure

A biological polymer composed of repeating amino acid monomers with distinct amine groups, central carbons, carboxyl groups, and variant R-groups.

Essential Amino Acids

Amino acids that cannot be synthesized by the human body and must be obtained from food; $9$ of the $20$ amino acids are essential.

Digestive Enzymes

Proteins that break down food molecules in the digestive system so they can be absorbed in the small intestine, such as lipase, amylase, pepsin, and lactase.

Contractile Proteins

Proteins with special filaments that slide over each other to allow animal movement, such as actin and myosin.

Defense Proteins

Protective proteins like antibodies produced by white blood cells that neutralize or mark pathogens for destruction.

Transport Proteins

Proteins that move substances around the body in the bloodstream or lymph, such as hemoglobin transporting oxygen in red blood cells.

Hormones

Regulatory proteins that travel in the blood to target organs to control body functions, such as insulin and glucagon regulating blood glucose levels.

Structural Proteins

Proteins that construct cellular frameworks like the cytoskeleton or outer body structures, including actin, keratin, and tubulin.

Storage Proteins

Proteins that provide a source of nutrition for developing animal embryos or plant seedlings, such as albumin in eggs.

Nucleic Acids

Macromolecules composed of $\text{CHONP}$ elements (carbon, hydrogen, oxygen, nitrogen, phosphorus) that carry, store, and transmit genetic information.

Nucleotide

The monomer unit of nucleic acids, composed of a phosphate group, a pentose sugar, and a nitrogenous base.

Deoxyribonucleic Acid (DNA)

A nucleic acid containing deoxyribose sugar that stores hereditary genetic material in organisms.

Ribonucleic Acid (RNA)

A nucleic acid containing ribose sugar that carries genetic instructions for cellular processes.

Deoxyribose Sugar vs. Ribose Sugar

Pentose sugars in nucleotides where deoxyribose has a hydrogen atom ($\text{H}$) at carbon $2$, whereas ribose has a hydroxyl group ($\text{OH}$) at carbon $2$.

Purines

Nitrogenous bases containing two rings in their chemical structure, including adenine and guanine.

Pyrimidines

Nitrogenous bases containing a single ring in their chemical structure, including cytosine, thymine (in DNA), and uracil (in RNA).

Carbohydrates

Macromolecules made of carbon, hydrogen, and oxygen ($\text{CHO}$) in ring structures that serve as a source of quick, short-term energy.

Lipids

Macromolecules composed of $\text{CHO}$ (sometimes $\text{P}$) with a glycerol backbone and long fatty acid hydrocarbon tails, serving as long-term energy storage and cell membrane components.