Key Concepts in Chemistry and Biological Molecules

Chemistry

The study of matter and its interactions.

States of Matter

Solid, liquid, and gas.

Energy

The capacity to do work, existing as:

Kinetic Energy

Energy in motion.

Potential Energy

Stored energy.

Chemical Energy

Stored in bonds (e.g., food molecules).

Electrical Energy

From charged particle movement.

Mechanical Energy

Moving matter (e.g., muscle movement).

Radiant Energy

Travels in waves (e.g., light, heat).

Efficiency

Energy conversion loses some energy as heat.

Elements in the Human Body

C, H, O, N: 96% of the body.

Trace Elements

Needed in small amounts.

Atoms

Subatomic Particles: Protons (+), neutrons (neutral), electrons (-).

Nucleus

Contains protons and neutrons.

Solutions

Homogeneous (e.g., saltwater).

Colloids

Heterogeneous; can change states (e.g., gelatin).

Suspensions

Visible particles that settle (e.g., blood).

Chemical Bonds

Types: Ionic, Covalent, Hydrogen.

Ionic Bond

Electron transfer; forms crystals (e.g., salt).

Covalent Bond

Electron sharing; can be polar or nonpolar.

Hydrogen Bond

Attraction between polar molecules (e.g., water).

Chemical Reactions

Types: Synthesis, decomposition, exchange, redox.

Exergonic Reaction

Releases energy.

Endergonic Reaction

Absorbs energy.

pH Scale

Measures H+ concentration (0-14).

Buffers

Resist pH changes.

Carbohydrates

Monomers: Monosaccharides (e.g., glucose).

Lipids

No monomers: Includes triglycerides, phospholipids, steroids.

Proteins

Monomers: Amino acids.

Nucleic Acids

Monomers: Nucleotides.

ATP

Structure: ATP = Adenosine + 3 phosphate groups.

ATP Function

Provides energy for cellular work.