Biochemistry

Matter and Atoms

Element vs. Compound: Elements are made up of one type of atom, while compounds consist of two or more elements. For example, H2O is a compound, and helium is an element.
The Periodic Table contains over 100 elements.
Structure of an Atom: Atoms are the smallest units of matter and consist of a nucleus (protons and neutrons) surrounded by electrons in an electron cloud.
Periodic Table Organization: Elements are arranged based on the number of protons, neutrons, and electrons. Periods represent rows and indicate the number of energy levels, while groups are columns indicating the number of valence electrons.
Drawing an Atom: Each energy level can hold a specific number of electrons: 2 in the 1st, 8 in the 2nd, and 8 in the 3rd.

Isotopes: Atoms with the same number of protons but different numbers of neutrons. Used in carbon dating.
Ions: Charged atoms that become stable by losing or gaining electrons. Examples include Ca 2+ (positive ion) and O 2- (negative ion).

Ion

Atomic #

Mass #

# of p

# of e-

# of n

Mg2+

N3-

Types of Bonds: Ionic bonds involve the transfer of electrons, while covalent bonds involve sharing electrons.
Ionic Bonds: Metals donate valence electrons to form positive ions, while nonmetals receive electrons to form negative ions. Bonds between Metals and Nonmetals
Covalent Bonds: Nonmetals share electrons to achieve stability without forming ions.
Bonding Examples: NaCl is an example of an ionic compound, while H2O and CH4 are examples of covalent compounds.

Organic Macromolecules: Large carbon-containing molecules that form the basis of life.
Monomer vs. Polymer: Monomers are individual subunits, while polymers are chains of monomers.
Macromolecule Formation: Monomers join to form macromolecules through condensation (dehydration synthesis) and break down through hydrolysis.

Type of Polymer	Atoms	Subunits(Monomer)	Drawing	Example
Carbohydrate	C,H,O	Monosaccharide(glucose, fructose)
Lipid	C,H,O	Fatty Acids, Glycerol	o
Protein	C,H,O,N	Amino Acid
Nucleic Acid	C,H,O,N,P	Nucleotide

Carbohydrates: Provide energy and structural support. Examples include glycogen(animal), starch, cellulose(plant). Subunits are monosaccharides (glucose, fructose).
Lipids: Nonpolar molecules like fats, oils, testosterone, and phospholipids. Functions include energy storage and cell membrane structure. Subunits are glycerol and fatty acids.
Proteins: Polymers of amino acids with diverse functions like muscle building, enzyme production, and hormone synthesis. Examples include enzymes, hormones, and muscles. Subunits are amino acids.
Nucleic Acids: DNA stores genetic information, while RNA helps in protein synthesis. Subunits are nucleotides.

Enzymes: Proteins that catalyze biochemical reactions by lowering activation energy. They are not consumed in the reaction.
Enzyme-Substrate Interaction: Enzymes have a lock-and-key mechanism where the substrate binds to the active site for the reaction to occur.
Factors Affecting Enzymes: Temperature, pH, and salinity influence enzyme activity.
Enzyme Denaturation: Changes in temperature or pH can denature enzymes, affecting their function.

Acids and Bases: Acids have a pH below 7, bases have a pH above 7, and neutral solutions have a pH of 7. Alkaline and base are the same thing. Acids release
Water Properties: Water is polar, resists temperature changes, expands when frozen, and acts as a solvent. It has cohesion and adhesion.
Hydrogen Bonds: Weak attractions between polar molecules like water, contributing to cohesion and adhesion.