Chapter 2 Part B: Organic Compounds and Biological Macromolecules

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Organic Compounds: Molecules that contain carbon and hydrogen, often with oxygen and nitrogen; typically found in living organisms. Examples include carbohydrates, lipids, proteins, and nucleic acids.
Inorganic Compounds: Molecules that do not contain both carbon and hydrogen together. Examples include water (H2O), salts, acids, and bases.
Key Difference: Organic compounds are generally larger, more complex, and associated with life processes, while inorganic compounds are simpler and include most minerals and water.

Carbohydrates: Monomer = monosaccharide (e.g., glucose); Polymer = polysaccharide (e.g., starch, glycogen)
Lipids: Not true polymers, but basic units include fatty acids and glycerol; complex lipids include triglycerides and phospholipids
Proteins: Monomer = amino acid; Polymer = polypeptide/protein
Nucleic Acids: Monomer = nucleotide; Polymer = DNA or RNA

Dehydration Synthesis: A chemical reaction that joins two monomers by removing a water molecule, forming a covalent bond. This process builds polymers.
Hydrolysis: A chemical reaction that breaks a covalent bond in a polymer by adding a water molecule, splitting the polymer into monomers.

Example: Formation of a disaccharide from two monosaccharides via dehydration synthesis; breakdown of a protein into amino acids via hydrolysis.

Triglycerides: Composed of glycerol and three fatty acids; function as energy storage molecules.
Phospholipids: Composed of glycerol, two fatty acids, and a phosphate group; major component of cell membranes.
Steroids: Four fused carbon rings; include cholesterol, hormones (e.g., testosterone, estrogen); function in membrane structure and signaling.
Eicosanoids: Derived from arachidonic acid; function as signaling molecules (e.g., prostaglandins).

Primary Structure: Linear sequence of amino acids in a polypeptide chain.
Secondary Structure: Local folding into alpha-helices or beta-pleated sheets, stabilized by hydrogen bonds.
Tertiary Structure: Overall three-dimensional shape of a single polypeptide, stabilized by interactions among R groups.
Quaternary Structure: Association of two or more polypeptide chains to form a functional protein.

Fibrous Proteins: Structural proteins, long and strand-like; insoluble in water. Examples: Collagen, keratin.
Globular Proteins: Functional proteins, compact and spherical; soluble in water. Examples: Enzymes, antibodies, hemoglobin.

DNA (Deoxyribonucleic Acid): Double-stranded helix, deoxyribose sugar, bases A-T-C-G, stores genetic information.
RNA (Ribonucleic Acid): Single-stranded, ribose sugar, bases A-U-C-G, involved in protein synthesis.

mRNA (Messenger RNA): Carries genetic code from DNA to ribosomes for protein synthesis.
tRNA (Transfer RNA): Brings amino acids to the ribosome during translation.
rRNA (Ribosomal RNA): Structural and functional component of ribosomes.

Function: Main energy currency of the cell; provides energy for cellular processes by transferring a phosphate group.
Exergonic Reaction: ATP hydrolysis releases energy:
Endergonic Reaction: ATP synthesis stores energy:
Enzymes:
- ATPase: Catalyzes ATP hydrolysis (exergonic reaction).
- ATP Synthase: Catalyzes ATP synthesis (endergonic reaction).

Macromolecule	Monomer	Polymer	Main Function
Carbohydrates	Monosaccharide	Polysaccharide	Energy storage, structure
Lipids	Fatty acids, glycerol	Triglycerides, phospholipids	Energy storage, membranes, signaling
Proteins	Amino acid	Polypeptide	Structure, enzymes, transport
Nucleic Acids	Nucleotide	DNA, RNA	Genetic information, protein synthesis