Biology Lecture Notes Flashcards

Definitions

• Ions: atoms or molecules with a net electric charge due to the loss or gain of electrons.
• Cations: positively charged ions.
• Anions: negatively charged ions.
• Electronegativity: tendency of an atom to attract a shared pair of electrons in a chemical bond.
• Isomers: molecules with the same molecular formula but different structural formulas.
• Anabolic reactions: synthesis of complex molecules from simpler ones; requires energy (endergonic).
• Catabolic reactions: breakdown of complex molecules into simpler ones; releases energy (exergonic).
• Endergonic reactions: reactions that require energy input.
• Exergonic reactions: reactions that release energy.

Bonding

• Ionic bonds: formed through the transfer of electrons between atoms.
• Covalent bonds: formed through the sharing of electrons between atoms.
• Hydrogen bonds: weak bonds between hydrogen and electronegative atoms (e.g., O, N).
• London dispersion forces: temporary attractive force in molecules due to temporary dipoles.
• Dipole-dipole interactions: attractive forces between polar molecules.

Importance of Water

• Polarity: Water is polar, allowing it to dissolve other polar substances.

Functional Groups

• Phosphate: -PO_4^{3-}
• Carbonyl (ketone, aldehyde): -C=O
• Carboxyl: -COOH
• Hydroxyl: -OH
• Amino: -NH_2

Biological Molecules

• Carbohydrates: Monomer - monosaccharide, Polymer - polysaccharide.
• Fats: Monomers - fatty acids and glycerol, Polymer - triglyceride (not a true polymer).
• Nucleic acids: Monomer - nucleotides, Polymer - DNA, RNA.
• Proteins: Monomer - amino acids, Polymer - polypeptide.

Cell Membrane

• Structure: phospholipid bilayer with embedded proteins.
• Function: controls the movement of substances in and out of cells.
• Components: phospholipids, proteins, cholesterol.
• Hydrophilic: water-attracting.
• Hydrophobic: water-repelling.
• Movement: diffusion, osmosis (isotonic, hypertonic, hypotonic), facilitated transport, active transport, bulk transport.

Enzymes

• Catalyze biological reactions.

Unit 2: Metabolic Processes

• Redox reactions: involve the transfer of electrons.
• Cellular respiration: breakdown of glucose to produce energy.
• Types of reactions: substrate-level and oxidative phosphorylation.
• Mitochondrial structure.
• Aerobic respiration: glycolysis, pyruvate oxidation, Krebs cycle.

Anaerobic Respiration

• Lactic acid fermentation.
• Alcohol fermentation.

Photosynthesis

• Leaf structure.
• Chloroplast structure.
• Stomata.
• Light reaction: ETC and photosystems.
• Calvin cycle.
• Photorespiration: C3 and CAM plants.

Unit 3: Molecular Genetics

• DNA: history, structure, replication, extraction.
• Central dogma: DNA >> RNA >> Protein.
• DNA vs. RNA: similarities and differences.
• Protein synthesis: transcription, translation.
• Mutations: point (silent, missense, nonsense), frameshift.
• Genetic Technologies: gel electrophoresis, PCR, CRISPR.
• Operons: trp and lac operon.

Unit 4: Homeostasis

• Feedback Systems: positive vs. negative feedback.
• Thermoregulation.
• Central and Peripheral Nervous System: reflex arc.
• Types of hormones.
• Endocrine System: glands (pituitary, pancreas, thyroid, parathyroid, adrenal).
• Neuron: structure, nerve impulse.
• Excretory system: parts, urine formation.