1.1.1 Matter & Energy govern the properties of life

Matter, composed of atoms and molecules, forms the physical substance of living organisms. Energy, the capacity to do work, drives all biological processes.

1.1.2 The atom is the fundamental unit of matter

Atoms are the basic units of matter consisting of protons, neutrons, and electrons.

1.1.3 Atoms combine to form molecules linked by chemical bonds

Molecules form when atoms bond together through chemical bonds:

• Covalent bonds: Atoms share electrons
• Ionic bonds: Electrons are transferred between atoms
• Hydrogen bonds: Weak attractions between molecules

1.1.4 Carbon is the backbone of organic molecules

Carbon's ability to form four covalent bonds allows for the creation of complex organic molecules necessary for life:

• Carbohydrates: Energy storage and structural components
• Lipids: Energy storage, cell membranes, and signaling
• Proteins: Structural support, enzymes, transport, and regulation
• Nucleic acids: Genetic information storage and transfer