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.