Basic and Applied Biomedical Sciences
What the exam expects
Questions in this domain test whether you can connect structure to function and mechanism to clinical consequence. Prioritise: anatomy of the head and neck (cranial nerve branches and their foramina, the pterygopalatine fossa, the course of the inferior alveolar and lingual nerves, venous drainage and the cavernous sinus, fascial spaces of the neck); physiology (action potential and nerve conduction, cardiac output and blood pressure regulation, renal handling of sodium and water, acid–base compensation, calcium homeostasis via PTH and vitamin D, haemostasis); histology (epithelial types and junctions, the four periodontal tissues, bone remodelling units, dental pulp organisation); biochemistry (glycolysis, Krebs cycle, oxidative phosphorylation, enzyme kinetics, collagen synthesis and vitamin C, porphyrin and bilirubin pathways); microbiology (Gram-positive vs Gram-negative structure, virulence factors, sterilisation vs disinfection, common oral flora); pathology (inflammation, wound healing, neoplasia nomenclature, cell injury and apoptosis); and pharmacology (receptor types, pharmacokinetics - first-order elimination, half-life, volume of distribution - and the drug classes used daily: local anaesthetics, NSAIDs, antibiotics, anticoagulants, bisphosphonates).
Traps to watch
- Confusing pharmacodynamics (what the drug does) with pharmacokinetics (what the body does to the drug).
- Mixing up the lingual nerve (sensation, chorda tympani hitch-hikes) and the inferior alveolar nerve (motor to mylohyoid via the nerve to mylohyoid).
- Assuming a drug with a short half-life needs fewer doses - it needs more frequent dosing.
- Forgetting that first-order elimination means a constant fraction cleared per unit time, not a constant amount.
Worked rule of thumb
Half-life arithmetic: after n half-lives, roughly 100/2ⁿ percent of the drug remains. A drug with a 6-hour half-life retains about 25% at 12 hours and about 3% at 30 hours - useful for estimating when an antibiotic or sedative has effectively cleared.