Building Blocks for Understanding

SI Units

SI Units

The International System of Units (SI) is the standard system of measurement used in science

Accuracy

How close a measured value is to the true value

Precision

How close repeated measurements are to each other.

protons, neutrons, and electrons

Atoms are made up of:

Protons

Positively charged particles in the nucleus

Neutrons

Neutral particles in the nucleus

Electrons

Negatively charged particles orbiting the nucleus.

Atomic Number (Z)

The number of protons in an atom.

Mass Number (A)

The total number of protons and neutrons in an atom.

Isotopes

Atoms of the same element with different numbers of neutrons.

2, 8

Electron Configuration

Shells and Energy Levels: Electrons occupy energy levels or shells around the nucleus.

• First Shell: Can hold up to___electrons.

• Second Shell: Can hold up to __ electrons

Elements

Pure substances consisting of only one type of atom.

Compounds

Substances formed from two or more elements chemically bonded together

Ionic Bonds, Covalent Bonds

Types of Chemical Bonds

Ionic Bonds

Sharing of electrons between atoms.

Covalent Bonds

Sharing of electrons between atoms.

Mixtures

A combination of two or more substances that are not chemically bonded

Homogeneous Mixtures

Mixtures that are uniform composition throughout.

Heterogeneous Mixtures

Mixtures that are non-uniform composition

Synthesis Reaction, Decomposition Reaction, Single Replacement Reaction, Double Replacement Reaction

Types of Chemical Reactions

Synthesis Reaction

Two or more simple substances combine to form a more complex substance.

Decomposition Reaction

A complex substance breaks down into simpler substances.

Single Replacement Reaction

One element replaces another in a compound

Double Replacement Reaction

Exchange of ions between two compounds

Law of Conservation of Mass

Mass is neither created nor destroyed in a chemical reaction.

Exothermic Reactions

type of reaction that release energy, usually in the form of heat.

Endothermic Reactions

types of reaction that absorbs energy

Carbohydrates

Organic compounds made up of carbon, hydrogen, and oxygen

Monosaccharides

Simple sugars

Disaccharides

Two monosaccharides bonded together

Polysaccharides

Long chains of monosaccharides (e.g., starch, glycogen, cellulose).

Proteins

Composed of amino acids linked by peptide bonds

Lipids

Structure: Made up of glycerol and fatty acids.

Functions: Energy storage, insulation, and making up cell membranes

DNA (deoxyribonucleic acid) and RNA (ribonucleic acid).

types of nucleic acid

• All living organisms are composed of one or more cells.

• The cell is the basic unit of life.

• All cells arise from pre-existing cells.

Principles of Cell Theory

Prokaryotic Cells

Cells that are simple and lack a nucleus

Eukaryotic Cells

Cells that are complex, with a nucleus and membrane-bound organelles

Nucleus

cell organelle that contains genetic material (DNA).

Mitochondria

Cell organelle that is the powerhouse of the cell, produces energy (ATP).

Ribosomes

Cell organelle that synthesize proteins

Chloroplasts

Cell organelle that is the site of photosynthesis in plant cells

Cell Membrane

Cell organelle that regulates what enters and exits the cell.

Photosynthesis, Cellular Respiration

What are the cellular processes?

Photosynthesis

Conversion of light energy into chemical energy in plants.

Cellular Respiration

Process of breaking down glucose to produce ATP.