Biomolecules and Nutrition: Lipids, Proteins, Nucleic Acids, Water, Vitamins & Minerals, and Eating Disorders

Vocabulary flashcards covering Lipids, Proteins, Nucleic Acids, Water, Vitamins & Minerals, and Eating Disorders.

Lipids

Nonpolar, water-insoluble biomolecules with a glycerol backbone and three fatty acid tails; includes triglycerides; energy storage is high.

Triglyceride

A lipid with a glycerol backbone bound to three fatty acid tails; the main storage form of lipids in organisms.

Hydrophobic

A property of lipids: nonpolar and not soluble in water.

Phospholipids

Lipids with a glycerol backbone, two fatty acids, and a phosphate-containing head; major component of cell membranes.

Fats

Animal-derived lipids (e.g., butter, lard) often solid at room temperature.

Oils

Plant-derived lipids (e.g., olive oil, safflower) typically liquid at room temperature.

Energy density of lipids

Lipids store about 2.25 times more energy per gram than carbohydrates or proteins.

Proteins

One of the main building blocks of cells; can be structural, enzymatic, hormonal, or involved in transport and defense.

Amino acids

Monomer units of proteins that are joined by peptide bonds to form polypeptides.

Peptide bond

Covalent bond linking amino acids in a polypeptide chain.

Primary structure

Linear sequence of amino acids in a protein.

Secondary structure

Local folding of the polypeptide into structures like helices or sheets.

Alpha-helix

A right-handed coiled secondary structure in proteins.

Beta-pleated sheet

A sheet-like secondary structure formed by hydrogen bonding between strands.

Tertiary structure

Three-dimensional folding of a protein due to side-chain interactions.

Quaternary structure

Structure of a protein formed from multiple polypeptide chains.

Enzymes

Proteins that act as biological catalysts to speed up chemical reactions.

Hormones (protein messengers)

Protein-based signaling molecules that regulate various physiological processes.

Myosin

Motor protein involved in muscle movement.

Hemoglobin

Protein in blood that transports oxygen.

Collagen

Structural protein in connective tissues.

Keratin

Structural protein in hair, nails, and skin.

Antibodies

Proteins of the immune system that defend against pathogens.

Energy from amino acids

Amino acids can be used for energy if needed, but this is less efficient than using carbohydrates or lipids.

Nucleic acids

Macromolecules that direct growth and development via genetic code; include DNA and RNA.

DNA

Deoxyribonucleic acid; stores genetic information; sugar is deoxyribose; typically double-stranded.

RNA

Ribonucleic acid; involved in protein synthesis; sugar is ribose; typically single-stranded.

Codons

Three-nucleotide sequences in DNA or RNA that code for a specific amino acid.

Water in the body

About 55–60% of body weight; essential for cellular processes, digestion, and maintaining blood volume.

Intercellular fluid

Fluid inside cells that participates in chemical reactions and transport.

Blood volume maintenance

Water helps maintain circulatory volume and pressure.

Water loss routes

Water is continually lost via urine, sweat, and respiration.

Vitamins

Organic compounds required in small amounts; fat-soluble vitamins (A, D, E, K) can be stored; some can cause toxicity (e.g., vitamin A overdose).

Fat-soluble vitamins

Vitamins A, D, E, and K; stored in body fat and liver; not easily excreted.

Minerals

Naturally occurring inorganic elements (e.g., calcium, phosphorus) required for cellular processes and repair (e.g., bones).

Calcium

Mineral essential for bones/teeth, muscle function, and nerve signaling.

Phosphorus

Mineral important for bones and energy transfer (ATP) and genetic material.

Bulimia

Psychological condition with cycles of binge eating followed by purging to prevent weight gain.

Anorexia nervosa

Psychological condition with an obsession with weight loss leading to malnutrition.

Overeating/Obesity

Excessive eating that leads to stored body fat; can be psychological or hereditary.