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Molecular biology: DNA structure and replication (Watson-Crick double helix; B-DNA; nucleosome structure — histone octamer; H2A; H2B; H3; H4 — DNA wrapped 1.65 times; chromatin compaction — 30nm fibre; topoisomerase I and II — solve topological problems; replication fork machinery — ORC — origin recognition complex; MCM helicase; Pol alpha primase; Pol delta PCNA — leading strand; Pol epsilon; lagging strand — Okazaki fragments; RFC clamp loader; RNaseH; Fen1; DNA ligase I); transcription (RNA Pol II — GTFs — TFIID — TBP and TAFs — TFIIB; TFIIF; TFIIE; TFIIH — kinase — Ser5 and Ser2 CTD phosphorylation; promoter — TATA box; Inr; DPE; enhancers — looping — cohesin; CTCF — TADs — topologically associating domains; chromatin remodelling — SWI/SNF — BAF complex; histone modifications — H3K4me3 active promoters; H3K27ac active enhancers; H3K27me3 Polycomb repression; H3K9me3 heterochromatin; pre-mRNA processing — 7mGppp cap; poly(A) signal — AAUAAA — CPSF; CstF; cleavage and polyadenylation; splicing — spliceosome — snRNPs — U1; U2; U4; U5; U6 — 5'SS; BP; PPT; 3'SS recognition; alternative splicing — cassette exon; intron retention; mutually exclusive — tissue-specific — NOVA1; RBFOX proteins); translation (ribosome — 40S — 18S rRNA — 60S — 5S; 5.8S; 28S rRNA — 80S eukaryotic; initiation — cap-dependent — eIF4E; eIF4G; eIF4A helicase; 43S PIC; scanning; start codon; IRES — cap-independent; elongation — EF-Tu; GTP; A/P/E sites; peptidyl transferase — 23S rRNA ribozyme; termination — eRF1; eRF3; ribosome rescue — Pelota; PELO); gene regulation (lac operon — negative control; arabinose operon — positive and negative; lambda phage — CI repressor — cI gene; Cro; lytic vs lysogenic switch; eukaryotic transcription factors — zinc finger; helix-turn-helix; leucine zipper; bHLH; p53 — tetramer — DNA damage response; NF-kB; Wnt — beta-catenin — TCF/LEF; Notch — NICD; Sonic Hedgehog — Gli; Hippo — YAP/TAZ).

Cell biology: cell signalling (receptor tyrosine kinases — EGFR dimerisation; autophosphorylation; Grb2-SOS-Ras-RAF-MEK-ERK MAPK cascade; PI3K-Akt-mTORC1; PTEN tumour suppressor; GPCRs — adenylyl cyclase; PKA; PLCbeta — IP3 — ER Ca2+ release — calmodulin — CaMKII; DAG — PKC; JAK-STAT — cytokine receptors — IFN signalling — STAT1; STAT3; oncogene mutation — KRAS G12D — 30% human cancers — RAF inhibitors; MEK inhibitors; second messengers — cAMP; cGMP — PDE5 inhibitors; Ca2+; IP3; DAG; ROS; NO — eNOS — sGC; cGMP; PKG; endocannabinoids); cell cycle control (CDKs — cyclin D/CDK4/6 — G1 phase; cyclin E/CDK2 — G1/S; cyclin A/CDK2 — S phase; cyclin B/CDK1 — mitosis; CDK inhibitors — p21 CIP1/WAF1; p27 KIP1; p16 INK4a; Rb — phosphorylation releases E2F; p53-p21 axis — DNA damage arrest; spindle assembly checkpoint — MAD1; MAD2; BUBR1; BUB3 — MCC — APC/C Cdc20 inhibition; securin-separase — cohesin cleavage — anaphase); apoptosis (intrinsic — cytochrome c — APAF1 — apoptosome — caspase 9 — caspase 3/7; Bcl-2 family — anti-apoptotic Bcl-2; Bcl-XL; MCL1 vs pro-apoptotic BAX; BAK; BH3-only proteins — BIM; PUMA; NOXA; mitochondrial outer membrane permeabilisation — MOMP; extrinsic — FasL — FADD — caspase 8; cross-talk — BID cleaved to tBID; p53 transcriptional target — PUMA; NOXA; cancer resistance — Bcl-2 overexpression — Philadelphia chromosome CML — venetoclax targets BCL-2); autophagy (ULK1/2 — mTORC1 inhibition initiates — Beclin1 — PI3K class III — ATG14 — omegasome; ATG5-ATG12-ATG16L1 — elongation; LC3-I to LC3-II — PE conjugation; selective autophagy — p62/SQSTM1; NBR1; NDP52; mitophagy — PINK1-Parkin; lipophagy; ER-phagy; xenophagy — bacterial clearance). Physiology: nervous system (action potential — Hodgkin-Huxley — Na+ inactivation gating; K+ slow opening; refractory period; myelination — saltatory conduction; nodes of Ranvier; synaptic transmission — SNARE — syntaxin; SNAP-25; synaptobrevin; calcium sensor synaptotagmin; AMPA; NMDA — long-term potentiation — Ca2+ — CaMKII — AMPA receptor insertion; GABA — Cl- influx — inhibition; LTP and LTD — synaptic plasticity — Hebb's rule; endocrine — hypothalamic-pituitary-adrenal axis — CRH; ACTH; cortisol — negative feedback; thyroid axis — TRH; TSH; T3/T4; immune evasion mechanisms).

Population ecology: population growth models (exponential growth — dN/dt = rN; logistic growth — dN/dt = rN(1-N/K) — K carrying capacity; Allee effect — positive density dependence below threshold — extinction debt; metapopulation dynamics — Levins model — patch occupancy — colonisation and extinction rates; island biogeography — MacArthur and Wilson 1963 — species-area relationship — S = cAz; z ≈ 0.25 for continental areas; immigration-extinction equilibrium; turnover; SLOSS debate — single large vs several small reserves; minimum viable population — PVA — population viability analysis — VORTEX model); community ecology (competition — Lotka-Volterra — isoclines — competitive exclusion principle — Gause — coexistence — niche differentiation — limiting similarity; keystone species — Paine 1966 — Pisaster ochraceus; ecosystem engineer — beaver — Castor canadensis; Beavers in Scotland reintroduction; trophic cascade — top-down control — Terborgh; bottom-up control — White; Oksanen; intermediate disturbance hypothesis — Connell 1978 — peak diversity at intermediate disturbance frequency; neutral theory — Hubbell 2001 — biodiversity and biogeography — dispersal limitation; stochastic drift — unified neutral theory — metacommunity; niche theory vs neutral theory debate); conservation biology (IUCN Red List categories — CR; EN; VU; NT; LC; DD; EX; EW — criteria A-E; population trends; range; quantitative analysis; sixth mass extinction — Ceballos et al. 2017 — vertebrate population loss; defaunation — Dirzo 2014; planetary boundaries — Rockstrom 2009; biodiversity loss boundary exceeded; CBD — Convention on Biological Diversity — Aichi targets 2010-2020; Kunming-Montreal Global Biodiversity Framework 2022 — 30x30 — 30% land and sea protected by 2030; UK Nature Recovery Network; Environment Act 2021 — 10% biodiversity net gain — mandatory England; RSPB; Wildlife Trusts; Natural England).

Evolution: natural selection mechanisms (Hardy-Weinberg equilibrium — p² + 2pq + q² = 1 — assumptions: no mutation; random mating; no genetic drift; no selection; no migration; deviations indicate evolution; directional; stabilising; disruptive selection; sexual selection — intrasexual competition; intersexual choice — Fisher runaway; honest signal — Hamilton and Zuk — parasite resistance; handicap principle — Zahavi; kin selection — Hamilton's rule — rb > c — inclusive fitness; coefficient of relatedness; altruism in Hymenoptera — haplodiploidy; eusociality evolution; reciprocal altruism — Trivers; multilevel selection — Wilson and Wilson — group selection debate); molecular evolution (neutral theory — Kimura 1968 — most mutations neutral; nearly neutral theory — Ohta — slightly deleterious mutations drift in small populations; molecular clock — rate of substitution; synonymous vs nonsynonymous substitutions — dN/dS ratio — positive selection dN/dS > 1 — MHC genes; purifying selection dN/dS < 1 — housekeeping; adaptive evolution at codon level — McDonald-Kreitman test; phylogenetics — maximum likelihood; Bayesian inference — MrBayes; BEAST — molecular phylogenetics; molecular clock calibration — fossil record; biogeography; PAML — positive selection; comparative genomics — synteny; gene family evolution; horizontal gene transfer); genetics (quantitative genetics — polygenic traits; heritability — h² = VG/VP; narrow-sense h² = VA/VP; additive; dominance; epistatic variance; twin studies; genome-wide association studies — GWAS — Manhattan plot; LD blocks — HapMap; 1000 Genomes; polygenic risk scores — PRS — clinical applications; epigenetics — DNA methylation — CpG islands; histone modification; chromatin accessibility — ATAC-seq; imprinting — IGF2; H19; Angelman; Prader-Willi syndromes; transgenerational epigenetic inheritance — evidence and controversy; RNA interference — miRNA; siRNA; lncRNA — XIST — X-inactivation; HOTAIR; chromatin looping).

Microbiology: bacterial physiology (peptidoglycan — murein sacculus — Gram-positive thick; Gram-negative thin + outer membrane — LPS — lipid A — O-antigen; teichoic acids — Gram-positive; bacterial secretion systems — Type III — needle complex — Yersinia Yop effectors; Type IV — Helicobacter pylori CagA; Type VI — toxin delivery; quorum sensing — N-acyl homoserine lactones — LuxI/LuxR homologs; biofilm formation — polysaccharide matrix — c-di-GMP signalling; virulence factors — toxins — cholera toxin ADP-ribosylation — Gs alpha; anthrax toxin — protective antigen; lethal factor; edema factor; MRSA — mecA — PBP2a — reduced penicillin binding affinity; beta-lactamases — TEM; CTX-M ESBL; KPC carbapenemase; antimicrobial resistance mechanisms — efflux pumps; target modification; enzymatic inactivation; WHO priority pathogens; AMR Action Plan); virology (virus lifecycle — attachment — receptor binding; entry — membrane fusion — influenza HA-NA; endosomal escape; uncoating; replication — +ssRNA — picornavirus IRES; -ssRNA — influenza RdRp in nucleus; dsDNA — herpesvirus nuclear replication; lentivirus — reverse transcription — integrase; HAART; assembly; budding; spread; viral immune evasion — MHC class I downregulation — HCMV US2; US3; US6; US11; IFN antagonism — influenza NS1; SARS-CoV-2 ORF3b; Nsp1; SARS-CoV-2 variants — spike protein mutations — D614G; Alpha; Delta; Omicron BA.2/BA.5/XBB — ACE2 binding; antibody escape; mRNA vaccines — BNT162b2 — modified uridine — LNP delivery). Immunology: innate immunity (PRRs — TLR4 — LPS — MyD88 — NF-kB; IFN regulatory factors — TRIF pathway; TLR3 — dsRNA — TRIF; TLR7/8 — ssRNA — MyD88; RIG-I; MDA5 — cytoplasmic RNA sensors — MAVS — STING pathway — cGAS-STING — dsDNA sensing — IFN-beta; NLRP3 inflammasome — IL-1beta; IL-18; pyroptosis — gasdermin D; complement — classical; lectin; alternative pathways — C3 convertase; MAC; opsonisation — C3b; CR3); adaptive immunity (T cell development — positive selection — TCR:pMHC affinity; negative selection — AIRE — self-tolerance; clonal deletion; regulatory T cells — FOXP3 — Treg; Th1 — IFN-gamma; Th2 — IL-4; IL-5; IL-13; Th17 — IL-17; TFH — CXCR5 — germinal centre; B cell development — V(D)J recombination — RAG1/RAG2; class switch recombination — AID — IgM to IgG; IgA; IgE; somatic hypermutation — affinity maturation; plasma cell differentiation; monoclonal antibodies — Fc engineering; bispecifics; CAR-T; checkpoint inhibitors — anti-PD-1 nivolumab; anti-CTLA-4 ipilimumab; immune checkpoint biology).

Neuroscience: neural circuits (sensory processing — visual cortex — V1 — simple cells — Hubel and Wiesel — orientation selectivity; complex cells; hypercomplex; V4 colour; MT/V5 motion; ventral stream — object recognition; dorsal stream — spatial; predictive coding — Rao and Ballard — cortical hierarchy; free energy principle — Friston; hippocampus — place cells — O'Keefe — grid cells — Moser — Nobel 2014 — spatial navigation; episodic memory consolidation; HM patient — hippocampal removal — anterograde amnesia — Milner; cerebellum — Purkinje cells — climbing fibres; parallel fibres — LTD — motor learning; basal ganglia — striatum — dopamine — reward prediction error — Schultz — temporal difference learning — reinforcement learning; Parkinson's — nigrostriatal dopamine loss — L-DOPA; DBS — subthalamic nucleus; prefrontal cortex — working memory — N-back task; executive function; DLPFC; cognitive control; dual-process theory — System 1 and System 2 — Kahneman — neural correlates); mental health neuroscience (depression — monoamine hypothesis — SERT; NET; MAO; neuroplasticity — BDNF — TrkB — synaptic plasticity — ketamine — NMDA antagonist — rapid antidepressant — mTOR activation; predictive processing models of depression; schizophrenia — dopamine hypothesis — D2 receptor — typical antipsychotics — EPS; glutamate hypothesis — NMDA hypofunction; serotonin — atypical antipsychotics; neurodevelopmental origins; autism spectrum disorder — SHANK3; NRXN; CNTN4 mutations; de novo CNVs; oxytocin; mirror neurons — Rizzolatti — controversy — broken mirror theory — Iacoboni critique). Developmental biology: pattern formation (Drosophila body plan — maternal effect genes — bicoid gradient; nanos; Toll pathway — dorsoventral; gap genes — hunchback; Krüppel; pair-rule genes — even-skipped; ftz; segment polarity — engrailed; wingless; Hox gene clusters — ANTP; BX-C — colinearity — spatial and temporal; vertebrate limb development — ZPA — Sonic Hedgehog — anterior-posterior patterning; AER — FGFs — proximal-distal; Wnt — dorsoventral; digit identity; evo-devo — divergent Hox expression; parallel evolution; heterochrony — paedomorphosis — axolotl; stem cells — embryonic — pluripotency — OCT4; SOX2; NANOG; iPSCs — Yamanaka factors — Nobel 2012; tissue-specific adult stem cells — intestinal crypt — Lgr5+ CBC cells; Wnt niche; haematopoietic stem cells — bone marrow; HSPC hierarchy; organoids — intestinal — Clevers; brain organoids — Lancaster — NATURE 2013).