Feb 8, Doc 1
Page 1: Matter and Atoms
Mass: Weight of matter.
Atoms: Smallest stable units of matter.
Types of atoms:
Protons (p+): Positively charged.
Neutrons (n): Electrically neutral.
Electrons (e-): Negatively charged.
Element: A substance made of the same atomic number.
Atomic Number: Total number of protons.
Mass Number: Total number of protons and neutrons.
Isotopes: Atoms with the same number of protons but different neutrons.
Mass number differs, does not account for electrons.
Page 2: Ions and Chemical Bonds
Ions: Charged atoms due to electron loss/gain.
Cations: Positively charged ions (loss of electrons).
Chemical Bonds (strongest to weakest):
Covalent: Strongest, sharing electrons.
Ionic: Formed between oppositely charged ions (transfer of electrons).
Hydrogen: Weakest, attraction between polar molecules.
Electrolytes: Ionic compounds that conduct electricity in water.
Page 3: Covalent and Hydrogen Bonds
Covalent Bonds: Sharing of electrons; forms molecules.
Types:
Single bond: One shared electron.
Double bond: Two shared electrons.
Nonpolar Covalent Bonds: Electrons shared equally (e.g., CO2).
Hydrogen Bonds: Weak bonds formed due to slight charge differences in molecules, plays a key role in water properties.
Page 4: Properties of Water
Important properties:
Lubrication.
Adhesion and cohesion.
Chemical reactivity.
Thermal Stability: High heat capacity and thermal inertia.
Polar Molecule: Asymmetrical structure causes polarity; important for forming ionic bonds.
Aqueous Solution: Anions and cations surrounded by water molecules.
Hydration Sphere: Layer of water surrounding ions in solution.
Page 5: Catabolism and Synthesis
Catabolism: Breakdown reactions; releasing kinetic energy from covalent bonds.
Example: ATP → ADP + P + ENERGY.
Synthesis: Formation of larger molecules from smaller ones.
Dehydration Synthesis: Involves water removal to form bonds.
Anabolism: Energy-requiring synthesis reactions (opposite of catabolism).
Page 6: Metabolic Pathway and Carbohydrates
Metabolic Pathway: Complex series of reactions to yield energy/products.
Reactions can be exergonic (release energy) or endergonic (require energy).
Carbohydrates: Organic molecules (1:2:1 ratio of C, H, O).
Major energy sources; includes sugars and starches.
Phospholipids and Glycolipids: Formed from diglycerides; have hydrophilic heads and hydrophobic tails.
Page 7: Proteins
Proteins: Most abundant organic molecules, composed of amino acids.
Contain carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur/phosphorus.
Structure consists of long chains of 20 different amino acids.
Amino Acids: Have central carbon, amino group, carboxyl group, and variable R group.
Protein Structure: Final shape often determined by interactions with water (Tertiary Structure).