Curriculum
Biology & Geology
Chapter 1 - Support and Movement in Living Organisms
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1.1Why is support needed?1.2Support in plants1.3Support in animals1.4The human skeletal system1.5First: the skeleton1.62.1.1 The vertebral column1.72.1.2 The skull (cranium)1.82.1.3 The thoracic cage1.92.1.4 The pectoral girdle and the upper limb1.102.1.5 The pelvic girdle and the lower limb1.11Second: cartilages1.12Third: joints1.13Fourth: ligaments1.14Fifth: tendons
2.1Movement in living organisms2.2Movement in plants2.3Systems that cooperate in movement2.4The muscular system2.5Structure of a skeletal muscle2.6How the nerve impulse reaches the muscle2.7The sliding-filament theory of muscle contraction (Huxley)2.8Muscle fatigue and cramp2.9Summary of coordination in movement2.10Comparison: voluntary and involuntary muscles2.11Key terms2.12Practical tips for answering exam questions
Chapter 2 - Hormonal Coordination in Living Organisms
0/321.1Control of body functions1.2What is a hormone?1.3Discovery of animal hormones — Starling (1905)1.4Plant hormones — Jensen (1913)1.5How scientists found out what hormones do1.6Characteristics of hormones1.7Types of glands in man1.8Position and structure1.9Hormones of the adenohypophysis (anterior lobe)1.10Hormones of the neurohypophysis (posterior lobe)1.11The thyroid gland1.12Diseases of the thyroid (due to hypo- or hypersecretion of thyroxine)1.13The parathyroid glands
2.1The adrenal (suprarenal) glands2.2Hormones of the cortex (steroids; controlled by ACTH)2.3Hormones of the medulla (amino-acid derivatives; controlled by nerves)2.4The pancreas as a mixed gland2.5Insulin2.6Glucagon2.7Diabetes mellitus (hyposecretion of insulin)2.8The sex glands (gonads)2.9Male sex hormones — androgens2.10Female sex hormones2.11Gastrointestinal hormones2.12Comparison between nervous and hormonal co-ordination2.13Summary table of the endocrine glands2.14Key terms2.15Negative feedback — the idea behind every endocrine gland2.16Antagonistic pairs2.17Hormones that are linked to the hypothalamus2.18Additional worked examples2.19Typical exam checklists
Chapter 3 - Reproduction in Living Organisms
0/331.1Importance of reproduction1.2Reproductive capacity1.3Methods of reproduction1.4Asexual reproduction1.5Sexual reproduction1.6Comparison between asexual and sexual reproduction1.7Alternation of generations1.82.4.1 Life cycle of Plasmodium (malaria parasite)1.92.4.2 Life cycle of a fern (Polypodium, Adiantum)
4.1The breeding cycle and the menstrual cycle4.2Fertilisation4.3Pregnancy and embryonic development4.4Contraception (birth control)4.5Multiple births and twins4.6Test-tube babies (in vitro fertilisation, IVF)4.7Cloning and embryo culture4.8Gamete banks and sex control4.9Ethical note4.10Practical observations (as listed at the end of the chapter)4.11Summary comparisons4.12Key terms
Chapter 4 - Immunity in Living Organisms
0/341.1The constant threat1.2Definition1.3Two systems working together1.4Worked example 1 — classifying a defence1.5Worked example 2 — one infection, both systems1.6Immunity in plants1.7Structural immunity1.8Biochemical immunity1.9Why are phenols "biochemical" but cork "structural"?1.10Worked example 3 — what does a cut do to a tree?1.11Worked example 4 — compare two plants1.12Summary table — plant immunity
2.1Overview2.2Lymphoid organs2.3Worked example 5 — why swollen glands?2.4Summary table — lymphoid organs2.5White blood cells (leukocytes)2.6Antigens2.7Helper chemicals2.8Worked example 6 — why do interferons protect neighbours?2.9Antibodies2.10Structure of an antibody2.11How antibodies act2.12Worked example 7 — classify the mechanism
3.1How the human body protects itself3.2Natural (innate) immunity3.3Worked example 8 — a cut finger3.4Acquired (specific, adaptive) immunity3.5Worked example 9 — why a virus-infected cell cannot be cleared by antibodies3.6Stages of the acquired response — primary and secondary3.7Worked example 10 — reading the response graph in words3.8Comparison tables for revision3.9Key terms3.10Final recap
Chapter 5 - Molecular Biology - DNA Structure and Function
0/431.1The question1.2Evidence 1 — Bacterial transformation (Griffith, then Avery)1.3Evidence 2 — Bacteriophages (Hershey and Chase)1.4Is DNA the genetic material of every organism?1.5Evidence 3 — The quantity of DNA in cells1.6Worked example 1 — interpreting a Griffith-type result1.7Worked example 2 — predict the Hershey–Chase outcome
2.1The structure of DNA2.2The data a model had to fit2.3The Watson–Crick model2.4Why the model fits the data2.5Worked example 3 — complementary strand2.6Worked example 4 — base percentages2.7Worked example 5 — a test for the type of nucleic acid2.8Why replicate?2.9The steps and the enzymes2.10Where replication starts2.11Summary of the enzymes2.12Worked example 6 — template and product2.13Worked example 7 — how many fragments?2.14Worked example 8 — speed of copying2.15DNA damage and repair2.16Worked example 9 — why does RNA virus mutate more?2.17Prokaryotes2.18Eukaryotes – chromatin and condensation2.19Comparison2.20Worked example 10 — packing ratio2.21The genome2.22Repetitive DNA2.23Worked example 11 — reasons2.24Definition2.25Kinds2.26Gamete and somatic mutations2.27Origin of mutations2.28Worked example 12 — classify2.29Key terms2.30Final recap
Chapter 6 - Molecular Biology - RNA, Protein Synthesis and Genetic Engineering
0/381.1Two main groups1.2One building plan for thousands of proteins1.3Worked example 1 — counting bonds1.4RNA: structure and difference from DNA1.5Worked example 2 — identify the nucleic acid1.6Messenger RNA (mRNA) and transcription1.7Ribosomal RNA (rRNA)1.8Transfer RNA (tRNA)1.9Comparison1.10Worked example 3 — transcription1.11Why a triplet code?1.12Properties of the code1.13The codon table (mRNA, read 5′→3′; for reference)1.14Counting rules1.15Worked example 4 — translate1.16Worked example 5 — from DNA to protein1.17Worked example 6 — a gene of 150 base pairs1.18Worked example 7 — the effect of a mutation1.19Initiation1.20Elongation1.21Termination1.22Polyribosomes1.23The whole pathway1.24Worked example 8 — number of peptide bonds1.25Worked example 9 — why polysomes?
2.1Modern techniques of molecular technology2.2Nucleic acid hybridisation2.3Restriction endonucleases2.4Cloning a gene in a plasmid2.5Reverse transcriptase and cDNA2.6Polymerase chain reaction (PCR)2.7Recombinant DNA and its applications2.8Worked example 10 — design a cloning experiment2.9Worked example 11 — hybridisation question2.10The Human Genome Project2.11Worked example 12 — why compare genomes?2.12Key terms2.13Final recap
Chapter 7 - Geology, Earth Sciences and Ecology
0/282.11 Minerals: importance and definition2.22 Formation and chemical groups of minerals2.33 Crystallography: crystal structure and crystal systems2.44 Optical properties of minerals2.55 Cohesive properties of minerals2.66 Rocks and their three types2.77 Igneous rocks2.88 Sedimentary rocks2.99 Metamorphic rocks2.1010 Weathering2.1111 The rock cycle
Text lesson
Plate Tectonics, Earthquakes, Weathering and Ecological Balance
Plate Tectonics, Earthquakes, Weathering and Ecological Balance
Overview
Overview
- Explain the movement of continents and plates by convection currents in the mantle.
- Distinguish the three kinds of plate movement and their geological results.
- Describe earthquakes, their types and their waves, and what the waves reveal about the Earth’s interior.
- Compare mechanical and chemical weathering, and explain isostatic balance of the crust.
🌳 Concept tree
- Plate Tectonics
- Earthquakes
- Weathering and Balance
├── The Earth as a dynamic planet
- │ ├── Lithosphere (crust + rigid upper mantle, ~100 km)
- │ └── Asthenosphere (~350 km, plastic, convection currents)
├── Continental drift — Wegener (1912)
- │ └── Pangaea, fitting coasts, paleomagnetism, paleoclimate, fossils
- ├── Plate tectonics — Isaacs, Oliver & Sykes (1968)
- │ ├── Divergent (constructive) → ocean ridges, Red Sea rift
- │ ├── Convergent (destructive) → Himalayas, Andes, trenches, island arcs
- │ └── Transform (conservative) → San Andreas, Gulf of Aqaba
├── Earthquakes
│ ├── Focus and epicentre
│ └── Volcanic, tectonic, plutonic (deep-focus)
- ├── Seismic waves — P
- S
- L recorded by the seismograph
├── Weathering
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| │ ├── Mechanical |
| freezethawthermalexpansion |
| │ └── Chemical |
| oxidationcarbonation |
| • |
| IsostasyAirymountainroots |
Plate Tectonics, Earthquakes, Weathering and Ecological Balance · 1 / 9
Introduction — the Earth is a dynamic planet
Introduction — the Earth is a dynamic planet
- The Earth has been in constant change since it formed; the rocks of the crust do not stay in their original state.
- They are subjected from time to time to internal and external forces that make them take new positions and shapes.
- The forces released from inside the Earth cause earthquakes, the agitation of seas and oceans, the advance or retreat of their waters over the land, and the shifting and movement of the continents relative to one another.
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| • |
| lithospheremadecrustplus |
| Below it lies the asthenosphere, about 350 km thick | a plastic rock material that behaves like a fluid under pressure and temperature | plasticrockmaterialbehaves |
| Convection-current eddies | spread through the asthenosphere and help the continents float and move over it | spreadthroughasthenospherehelp |
Plate Tectonics, Earthquakes, Weathering and Ecological Balance · 2 / 9
The theory of continental drift (Wegener)
The theory of continental drift (Wegener)
- In 1912 the scientist Alfred Wegener assumed that the continents were once a single giant land mass called Pangaea (“the mother of continents”), which began to break apart, separate and drift until it settled in its present positions — more than 200 million years ago.
The fit of the continental marginsthe east coast of South America matches the west coast of Africa.
Paleomagnetismtracing the direction of the magnetic needle preserved in ancient rocks.
Paleoclimateglacial deposits found in the south of several continents that are far apart today.
Matching fossils and geological structureacross the separated continents.
The question that remained
- What force moves the continents? The answer came with the theory of plate tectonics.
Plate Tectonics, Earthquakes, Weathering and Ecological Balance · 3 / 9
The theory of plate tectonics
The theory of plate tectonics
Isaacs, Oliver and Sykes (1968)→stated that the lithosphere is divided into major tectonic plates — continental, oceanic, or both together — which float on the plastic asthenosphere and move very slowly under the effect of the heat convection-current eddies.
Types of plate movement
Divergent (constructive)tension forces from rising convection currents drive two plates apart.
Convergent (destructive)compression forces from sinking convection currents collide two plates.
Transform (conservative)the edge of one plate slides horizontally past the edge of another, producing cutting transform faults.
- Oceanic plate with oceanic plate → a mid-ocean ridge and new oceans, as in the Atlantic Ocean.
- Continental plate with continental plate → a continental rift, as in the rifting of the Red Sea, produced by the Arabian plate moving away from the African plate.
- Continental with continental → huge fold mountain chains, as in the Himalayas.
- Continental with oceanic → the denser oceanic plate is subducted beneath the continental plate and melts in the mantle, forming volcanic mountain chains as in the Andes.
- Oceanic with oceanic → one plate sinks under the other, forming deep ocean trenches and volcanic island arcs.
Results of transform movement
- Large deformations and transform faults accompanied by violent volcanoes and earthquakes.
- Examples: the San Andreas fault and the Gulf of Aqaba.
Relation to geological structures
These movements produce the folds and faults already studied→compression produces folds and reverse faults, while tension produces normal faults.
Plate Tectonics, Earthquakes, Weathering and Ecological Balance · 4 / 9
Earthquakes and their types
Earthquakes and their types
- An earthquake is huge stored energy released suddenly from inside the Earth as elastic waves and vibrations that travel through the rocks and cause destruction in the crust.
- The focus is the point inside the Earth from which the energy is released.
- The epicentre is the point on the surface lying vertically above the focus, where the effect is usually most severe.
Volcanic earthquakeslocal tremors that accompany volcanic activity and do not extend far.
Tectonic earthquakesthe most common and most destructive type; they occur in zones of rock fracturing and plate sliding along faults.
Plutonic (deep-focus) earthquakestheir focus lies at great depth, sometimes more than 500 km below the surface.
Comparison
Causevolcanic: volcanic activity · tectonic: plate and fault movement · plutonic: great depth in the mantle.
Spreadvolcanic: local · tectonic: widespread · plutonic: deep focus.
Frequency and damagevolcanic: limited · tectonic: most common and most destructive · plutonic: less surface effect because the focus is far away.
Plate Tectonics, Earthquakes, Weathering and Ecological Balance · 5 / 9
Seismic waves and their recording
Seismic waves and their recording
- Seismic waves are recorded at observing stations by the seismograph.
Types of waves
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| Primary waves (P) |
| longitudinalcompressionalparticlesvibrate |
| Secondary waves (S) |
| transversecreststroughsright |
| Surface waves (L) |
| complexlonglargeamplitude |
What the waves revealed about the Earth’s interior
- The passage of P waves through the whole core with a change in their speed allowed scientists to identify a molten outer core and a solid inner core.
- The inability of S waves to cross the outer core proved that it is liquid (molten).
- Analysis of these waves divided the core into an outer core (about 2,100 km) and an inner core (radius about 1,386 km).
Earthquake intensity
- The intensity of an earthquake and its destructive effect are measured on the Modified Mercalli scale.
Plate Tectonics, Earthquakes, Weathering and Ecological Balance · 6 / 9
Weathering
Weathering
Weathering→is the breakdown and decomposition of rocks under the action of atmospheric agents at the surface. It is the first stage of the rock cycle: rocks crumble, then agents of transportation carry and deposit the debris to form sedimentary rocks. It is divided into mechanical and chemical weathering.
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| • | Breaking the rock into smaller pieces without changing its chemical or mineral composition | Breakingrocksmallerpieces |
| Freezing and thawing of water | in rock cracks: blocks separate and talus (scree) slopes form | rockcracksblocksseparate |
| Thermal expansion | caused by the difference in temperature between night and day in the desert | causeddifferencetemperaturebetween |
| Unloading |
| erosionburiedrocksrise |
| Comparison aspect | Main idea | Example | Keywords |
|---|---|---|---|
| • |
| — | Decompositionchangemineralchemical |
| Oxidation | dissolved oxygen acts on iron-rich rocks |
| dissolvedoxygenactsiron |
| Carbonation |
| — | carbonicacidformsdissolves |
Comparison
Chemical and mineral compositionmechanical: unchanged · chemical: changed, new minerals form.
Agentsmechanical: freeze–thaw, thermal expansion, unloading · chemical: oxidation, carbonation, water and air.
Resultmechanical: smaller pieces of the same rock · chemical: weaker and purer minerals.
Examplemechanical: exfoliation of granite · chemical: rusting of basalt, limestone caves.
Plate Tectonics, Earthquakes, Weathering and Ecological Balance · 7 / 9
Isostatic balance and the ecological balance of the crust
Isostatic balance and the ecological balance of the crust
Isostatic balance (Airy’s theory)→the Earth’s crust is in a state of permanent balance even though its rocks differ in density and thickness. This appears in the oceanic crust (sima, higher density) and the continental crust (sial, lower density and greater thickness), which are in constant equilibrium.
- Large mountain chains are made of light rock with an average density of about 2.7 g/cm3.
- They have deep roots in the denser mantle rocks reaching a depth of several times their height (about 4 times, so the total depth is about 5 times the visible height).
- A mountain resembles a floating iceberg the greater part is submerged below.
- Erosion breaks up the mountain peaks and carries the debris to settle in sedimentary basins.
- The load on the mountain decreases while the load on the basin increases, producing a difference in pressure.
- Plastic mantle material moves from beneath the high-pressure zone (the basin) toward beneath the low-pressure zone (the mountain), so the mountain rises and the balance is restored.
- This repeats over millions of years.
- Isostasy keeps the crust stable and limits changes in the levels of land and sea.
- Weathering, transportation and deposition constantly reshape the surface, while the balancing mechanisms preserve its overall stability.
- It joins the internal forces (tectonic movements and earthquakes) with the external forces (weathering and erosion) in one balanced cycle.
Lesson summary
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| Continental drift | one mass (Pangaea) that broke apart and drifted | massPangaeabrokeapart |
| Plate tectonics |
| platesfloatasthenospheremove |
| Earthquakes |
| focusepicentrevolcanictectonic |
| Waves |
| fastestthroughmediasolids |
| Weathering |
| mechanicalcompositionalchangechemical |
| Isostasy |
| lightmountainsdeeproots |
Plate Tectonics, Earthquakes, Weathering and Ecological Balance · 8 / 9
Ministry exam traps
Ministry exam traps
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| S waves through the core. | The absence of S waves beyond the outer core — not the slowdown of P waves — is the direct proof that the outer core is liquid | absencebeyondouterslowdown |
| Which plate subducts. |
| continentaloceaniccollisionalways |
| Red Sea vs. Himalayas. |
| riftingdivergentresultcollision |
| Mechanical weathering changes nothing chemically. |
| Exfoliationgraniteeventhough |
| Mountain root ratio. |
| timesvisibleheightgiving |
| First stage of the rock cycle. | Weathering comes before transportation and deposition — it is what makes sedimentary rocks possible | Weatheringcomesbeforetransportation |
| Intensity scale. |
| EarthquakedestructionModifiedMercalli |
Plate Tectonics, Earthquakes, Weathering and Ecological Balance · 9 / 9
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