Human Biology: Chemistry of Life chapter 2

Chapter 2

Matter

Anything that has mass and takes up space; exists in solid, liquid, gas, or plasma forms.

Element

Basic building blocks of matter that cannot be broken down by chemical means.

Isotope

Atoms of the same element with a different number of neutrons, differing in atomic mass.

Ionic Bond

Attraction between a positive and negative ion resulting from the transfer of electrons.

Covalent Bond

A bond formed when atoms share electrons to fill their valence shells.

Hydrogen Bond

Attraction between a slightly positive hydrogen atom and a slightly negative atom (like oxygen or nitrogen).

pH Scale

A measure of acidity or basicity, ranging from 0 to 14, where 7 is neutral.

Buffer

A solution that resists changes in pH when acids or bases are added.

Monosaccharide

A single sugar molecule; the simplest form of carbohydrates.

Disaccharide

A carbohydrate composed of two monosaccharides joined by a dehydration reaction.

Polysaccharide

Complex carbohydrates consisting of long chains of monosaccharide units.

Triglycerides

Lipids made of one glycerol and three fatty acids, serving as major energy storage.

Amino Acid

The subunits that make up proteins, containing an amino group, carboxyl group, and an R group.

Peptide Bond

The polar covalent bond formed between two amino acids.

Nucleotide

Building blocks of nucleic acids, consisting of a phosphate group, a sugar, and a nitrogenous base.

ATP (Adenosine Triphosphate)

A high-energy molecule that serves as an energy carrier in cells.