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Every concept in the canon, grouped by unit. Press ⌘K to search.

123
concepts
25
units
6
threads

BU-101 · Cell Biology 6

T-001
All living things are made of cells, and cells arise only from pre-existing cells.
T-002
Two fundamentally different cellular architectures.
T-003
Each organelle's form is matched to its role.
T-004
A dynamic lipid bilayer studded with mobile proteins.
T-005
How a cell duplicates and divides its contents faithfully.
T-006
Mitochondria and chloroplasts descend from engulfed bacteria.

BU-102 · Biological Molecules 5

T-007
From amino-acid sequence to folded, functional shape.
T-008
Biological catalysts that speed reactions without being consumed.
T-009
Complementary base pairing on two antiparallel strands.
T-010
Amphipathic molecules spontaneously form bilayers.
T-011
Sugars as energy stores and structural polymers.

BU-103 · Genetics 5

T-012
Paired alleles separate into different gametes.
T-013
Genes on different chromosomes are inherited independently.
T-014
Predicting the 9:3:3:1 ratio of two traits.
T-015
Nearby genes tend to be inherited together.
T-016
Inheritance of genes carried on the sex chromosomes.

BU-104 · Evolution & Natural Selection 5

T-017
Differential survival and reproduction of heritable variation.
T-018
Reproductive success shapes the traits of a population.
T-019
How reproductive isolation gives rise to new species.
T-020
Homology, fossils and molecules point to shared ancestry.
T-021
Traits favoured through mate choice and competition.

BU-105 · Ecology 5

T-022
Energy dissipates as it passes up a food chain.
T-023
Growth slows as a population nears carrying capacity.
T-024
Two species cannot occupy the same niche indefinitely.
T-025
Coupled cycles of predator and prey abundance.
T-026
How carbon and nitrogen move through ecosystems.

BU-106 · Organismal Physiology 4

T-027
Stabilising the internal environment against disturbance.
T-028
Passive movement of molecules down a gradient.
T-029
Why exchange surfaces are thin, moist and large.
T-030
Why large organisms need circulatory systems.

BU-201 · Molecular Biology 5

T-031
Information flows DNA to RNA to protein.
T-032
Each old strand templates a new complementary one.
T-033
Copying a gene into messenger RNA.
T-034
Reading codons to build a polypeptide.
T-035
How changes in DNA sequence alter proteins.

BU-202 · Cell Signalling & Membranes 5

T-036
Passive, facilitated and active movement across membranes.
T-037
Converting an external signal into a cellular response.
T-038
Specificity and affinity in molecular recognition.
T-039
Amplifying and relaying signals inside the cell.
T-040
The Nernst equation applied to ion gradients.

BU-203 · Microbiology 5

T-041
Lag, exponential, stationary and death phases.
T-042
Evolution in action under drug selection.
T-043
Sharing genes between unrelated lineages.
T-044
The lytic and lysogenic strategies.
T-045
The many ways microbes extract energy.

BU-204 · Population & Molecular Genetics 5

T-046
Allele and genotype frequencies in an idealised population.
T-047
Random sampling changes allele frequencies.
T-048
Migration mixes alleles between populations.
T-049
Why harmful alleles persist at low frequency.
T-050
The genetic cost of mating with relatives.

BU-205 · Animal Physiology 5

T-051
The all-or-nothing electrical impulse of a neuron.
T-052
Cooperative oxygen binding by haemoglobin.
T-053
The countercurrent multiplier concentrates urine.
T-054
The sliding-filament mechanism of the sarcomere.
T-055
Endocrine control of physiological state.

BU-206 · Plant Biology 5

T-056
Turning light into ATP and NADPH.
T-057
Fixing carbon dioxide into sugar.
T-058
How water is pulled up a plant.
T-059
Directional growth in response to stimuli.
T-060
Trading gas exchange against water loss.

BU-207 · Developmental Biology 5

T-061
One genome gives rise to many cell types.
T-062
Concentration gradients supply positional information.
T-063
Master genes that specify anatomy.
T-064
Cells directing the fate of their neighbours.
T-065
Programmed cell death sculpts developing tissues.

BU-301 · Immunology 5

T-066
Two coordinated layers of defence.
T-067
How lymphocytes specific to a pathogen are amplified.
T-068
Generating a near-limitless repertoire from limited genes.
T-069
Displaying cellular contents to T cells.
T-070
The basis of long-lasting immunity and vaccines.

BU-302 · Neuroscience 5

T-071
Chemical communication across the synapse.
T-072
Summing excitatory and inhibitory inputs.
T-073
A cellular mechanism of learning and memory.
T-074
Converting physical stimuli into neural signals.
T-075
How spikes represent information.

BU-303 · Molecular Genetics & Genomics 6

T-076
Coordinated regulation of bacterial genes.
T-077
Enhancers, chromatin and transcription factors.
T-078
Heritable change without altered DNA sequence.
T-079
Exponential amplification of a DNA target.
T-080
Reading the order of bases in a genome.
T-081
Programmable, targeted genome editing.

BU-304 · Evolutionary Biology 5

T-082
Reconstructing evolutionary relationships from data.
T-083
Dating divergence from accumulated substitutions.
T-084
Hamilton's rule explains altruism among relatives.
T-085
Reciprocal evolutionary change between interacting species.
T-086
Most molecular evolution is selectively neutral.

BU-305 · Ecology & Population Dynamics 5

T-087
Colonisation and extinction across habitat patches.
T-088
Species richness from area and isolation.
T-089
How communities assemble and change over time.
T-090
Species with outsized effects on community structure.
T-091
Contrasting life-history strategies.

BU-306 · Structural Biology & Biophysics 5

T-092
The thermodynamics that select the native state.
T-093
Determining structure from diffraction.
T-094
The Michaelis-Menten model of catalysis.
T-095
Control by binding at a site away from the active site.
T-096
Proteins that convert chemical energy into motion.

BU-307 · Cancer Biology 5

T-097
The genetic accelerators and brakes of cancer.
T-098
The capabilities a tumour must acquire.
T-099
Surveillance that guards against damaged division.
T-100
How tumours secure a blood supply and spread.
T-101
Cancer progression as natural selection.

BU-308 · Systems Biology 4

T-102
The logic of cellular decision-making.
T-103
Sources of robustness and oscillation.
T-104
Tracing material flow through a metabolic network.
T-105
Behaviour arising from interactions, not parts.

BU-401 · Bioinformatics & Computational Biology 5

T-106
Detecting homology by dynamic programming.
T-107
Fast approximate matching against large databases.
T-108
Distance and likelihood methods.
T-109
Finding genes and motifs probabilistically.
T-110
Finding structure in transcriptomic data.

BU-402 · Synthetic Biology & Genetic Engineering 4

T-111
Cutting and joining DNA from different sources.
T-112
Carrying and replicating engineered DNA in cells.
T-113
Switches and oscillators built from biological parts.
T-114
Treating disease by correcting DNA.

BU-403 · Epidemiology & Disease Ecology 5

T-115
Compartmental modelling of an epidemic.
T-116
R0 sets the threshold for an outbreak.
T-117
The immune fraction that halts transmission.
T-118
Contact rate, infectiousness and spread.
T-119
Controlling disease at the population level.

BU-404 · Molecular Medicine 4

T-120
Absorption, distribution, metabolism and excretion of drugs.
T-121
Potency, efficacy and the therapeutic window.
T-122
Agonists, antagonists and binding.
T-123
Tailoring treatment to an individual's genome.