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IB Biology
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Course Introduction
Topic 1: Cell Biology
1.1 Introduction to cells
1.2 Ultrastructure of cells
1.3 Membrane Structure
1.4 Membrane Transport
1.5 The origin of cells
1.6 Cell Division
Topic 2: Molecular Biology
2.1 Molecules to Metabolism
2.2 Water
2.3 Carbohydrates and Lipids
2.4 Proteins
2.5 Enzymes
2.6 Structure of DNA and RNA
2.7 DNA Replication, Transcription and Translation
2.8 Cell Respiration
2.9 Photosynthesis
Topic 3: Genetics
3.1 Genes
3.2 Chromosomes
3.3 Meiosis
3.4 Inheritance
3.5 Genetic Modification
Topic 4: Ecology
4.1 & 4.2 Species, communities and ecosystems plus Energy Flow
4.3 Carbon Cycling
4.4 Climate Change
Topic 5: Evolution and Biodiversity
5.1 Evidence for Evolution
5.2 Natural Selection
5.3 Classification of biodiversity
5.4 Cladistics
Topic 6: Human Physiology
6.1 Digestion and absorption
6.2 The Blood System
6.3 Defence against infectious disease
6.4 Gas Exchange
6.5 Neurons and synapses
6.6 Hormones, homeostasis and reproduction
Topic 7: Nucleic Acids
7.1 DNA Structure and Replication
7.2 Transcription & Gene Expression
7.3 Translation
Topic 8: Metabolism Respiration & Photosynthesis
8.1
8.2
8.3
Topic 9: Plant Biology
9.1
9.2
9.3
9.4
Topic 10: Genetics & Evolution
10.1 Meiosis
10.2 Inheritance
10.3 Gene Pools & Speciation
Topic 11: Animal Physiology
11.1 Antibody Production & Vaccination
11.2 Movement
11.3 The Kidney & Osmoregulation
11.4 Sexual Reproduction
Option A: Neurobiology & Behaviour
A.1
A.2
A.3
A.4
A.5
A.6
Option C: Ecology & Conservation
C1: Species & Communities
C2: Communities & Ecosystems
C3: Impacts of Humans on Ecosystems
C4: Conservation of Biodiversity
C5: Population Ecology
C6: The Nitrogen & Phosphorus Cycles
Option D: Human Physiology
D1 Human Nutrition
D2 Digestion
D3 Functions of the Liver
D4 The Heart
D5 Hormones and Metabolism
D6 Transport of Respiratory Gases
Internal Assessment (IA)
Statistics
Helpful Resources
Exams and Revision
Past Exams
General Revision
Topic 1 Cells
Topic 2 Molecular Biology
Topic 3 Genetics
Topic 4 Ecology
Topic 5 Evolution and Biodiversity
Yr 11 Mid Year Exam Revision
Compulsory Practicals
Microscope and Calculations
Osmolarity
Enzymes
Mesocosm
Ventilation
Extended Essay Biology
IB Biology
C6: The Nitrogen & Phosphorus Cycles
Essential idea: Soil cycles are subject to disruption.
Understandings:
Nitrogen-fixing bacteria convert atmospheric nitrogen to ammonia.
Rhizobium
associates with roots in a mutualistic relationship.
In the absence of oxygen denitrifying bacteria reduce nitrate in the soil.
Phosphorus can be added to the phosphorus cycle by application of fertilizer or removed by the harvesting of agricultural crops.
The rate of turnover in the phosphorus cycle is much lower than the nitrogen cycle.
Availability of phosphate may become limiting to agriculture in the future.
Leaching of mineral nutrients from agricultural land into rivers causes eutrophication and leads to increased biochemical oxygen demand.
Applications and skills:
Application: The impact of waterlogging on the nitrogen cycle.
Application: Insectivorous plants as an adaptation for low nitrogen availability in waterlogged soils.
Skill: Drawing and labelling a diagram of the nitrogen cycle.
Skill: Assess the nutrient content of a soil sample.
Introductory Video
Powerpoint
C6 The nitrogen and Phosphorus Cycle HL
Videos
The Atmosphere.mp4
The Hydrologic and Carbon Cycles_ Always Recycle! - Crash Course Ecology #8.mp4
Video 7 - TESTING THE PH OF SOILS.mp4.mp4
Soil and Soil Dynamics.mp4
Water Resources.mp4
Worksheets and Activities
Nitrogen Cycle Cut and Paste
BioK QQ C.6 QP
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