Atoms, Molecules & Macromolecules Review

Flashcards covering key definitions and concepts related to atoms, molecules, macromolecules, and basic biochemistry from the lecture notes.

Abundant elements in human body

Oxygen, Carbon, Hydrogen, Nitrogen, Calcium, Phosphorus

Trace elements

Elements needed in small amounts, such as Iron, Iodine, Zinc

Atom's chemical behavior

Determined by its valence electrons

Isotopes

Atoms of the same element with different numbers of neutrons

Radioisotope

An unstable isotope that emits radiation (alpha, beta, gamma)

Physical half-life

The time it takes for a radioisotope to decay

Biological half-life

The time it takes for a substance to leave the body

Atom vs. Ion

An atom is neutral; an ion is charged

Cations

Positively charged ions (e.g., Na+, K+)

Anions

Negatively charged ions (e.g., Cl-, HCO3-)

Electrolytes

Charged ions in solution that regulate nerves, muscles, and fluid balance

Free radicals

Unstable molecules that damage cells

Antioxidants

Protect cells from damage caused by free radicals

Molecule vs. Compound

A molecule consists of 2+ atoms; a compound consists of 2+ different elements chemically bonded

Isomers

Molecules with the same chemical formula but different structural arrangements

Chemical bonds

Ionic, Covalent (polar/nonpolar), Hydrogen, Van der Waals forces

Water's biological importance

Its polarity and bond angle contribute to its roles as a solvent, in cohesion, and temperature regulation

Mixture vs. Compound

A mixture is not chemically bonded; a compound is chemically bonded

Solution

A homogeneous mixture, such as plasma in the body

Colloid

A mixture with suspended particles that do not settle, such as cytoplasm

Suspension

A heterogeneous mixture with particles that will settle, such as blood cells in blood

pH

A measure of hydrogen ion concentration

Buffers

Substances that resist changes in pH (e.g., bicarbonate buffer system)

Potential energy

Stored energy

Kinetic energy

Energy of motion

Decomposition reaction

A chemical reaction that breaks down substances

Synthesis reaction

A chemical reaction that builds up substances

Exchange reaction

A chemical reaction where atoms or ions are swapped between molecules

Metabolism

All chemical reactions occurring in the body, including catabolism and anabolism

Catabolism

Metabolic process of breaking down molecules

Anabolism

Metabolic process of building up molecules

Oxidation

Loss of electrons

Reduction

Gain of electrons

Carbohydrates

Organic compounds that primarily provide quick energy

Monosaccharides

Simple sugars like Glucose, Fructose, Galactose

Disaccharides

Sugars formed from two monosaccharides, e.g., Sucrose, Lactose, Maltose

Polysaccharides

Complex carbohydrates, e.g., Glycogen, Starch, Cellulose

Major lipid types

Fatty acids, Triglycerides, Phospholipids, Steroids

Proteins

Macromolecules made of 20 amino acids linked by peptide bonds

Amino acids

The building blocks of proteins

Peptide bonds

Bonds that link amino acids together to form proteins

Levels of protein structure

Primary, Secondary, Tertiary, Quaternary

Protein shape and function

A protein's specific shape determines its function; denaturation alters this shape and function

Functions of proteins

Act as enzymes, hormones, structural components, transport molecules, and defense mechanisms

Nucleic acids

DNA and RNA; molecules that store and transfer genetic information

ATP (Adenosine Triphosphate)

The body's main energy-carrying molecule, related to RNA nucleotides