OCR A Level Biology Revision Notes 2023

Overview

• Exam code: H420
• Resources for OCR A Level Biology course, including topics on development of practical skills, foundations in biology, exchange and transport, biodiversity, evolution & disease, communication, homeostasis & energy, and genetics, evolution & ecosystems.

Key Areas of Study

1. Development of Practical Skills in Biology

• Practical Skills: Written Assessment
  • Experimental Design
  • Identification of Variables
  • Evaluating Experimental Methods
  • Using Units
  • Presenting Experimental Data
  • Mathematical Analysis of Results
  • Drawing Conclusions
• Practical Skills: Endorsement Assessment
  • Ethical Use of Organisms
  • Aseptic Techniques
  • Dissection of Gas Exchange Surfaces in Fish & Insects
  • Drawing Cells from Blood Smears
  • Investigating Biodiversity Using Sampling
  • Data loggers & Computer Modelling
  • Investigating the Rate of Diffusion
  • Investigating Water Potential
  • Factors Affecting Membrane Structure & Permeability
  • Biochemical Tests (Reducing Sugars & Starch, Lipids, Proteins)
  • Chromatography
  • Serial Dilutions
  • Investigating the Rate of Transpiration
  • Using a Light Microscope

2. Foundations in Biology

• Cell Structure
  • Studying Cells, Using a Microscope, Drawing Cells
  • Magnification & Resolution, Eukaryotic Cells
  • Organelles & Protein Production
  • Cytoskeleton
  • Comparison of Prokaryotic & Eukaryotic Cells
• Biological Molecules
  • Properties and significance of Water
  • Monomers & Polymers
  • Carbohydrates: Monosaccharides, The Glycosidic Bond, Polysaccharides
  • Biochemical Tests for carbohydrates
  • Lipids & Ester Bonds, Lipids' structure & function
  • Biochemical Tests for Lipids
  • Proteins: Amino Acids, Peptide Bonds, Structure
  • Types of Proteins: Globular & Fibrous
  • Inorganic Ions
  • Finding concentration of substances
  • Chromatography
• Nucleotides & Nucleic Acids
  • Nucleotides & Phosphodiester Bonds
  • Phosphorylated Nucleotides
  • DNA Structure & Purification
  • DNA Replication, The Genetic Code, Transcription & Translation
• Enzymes
  • Role of Enzymes
  • Factors affecting enzyme activity: pH, Temperature, Concentration
  • Enzyme Inhibitors, Coenzymes, Cofactors & Prosthetic Groups
  • Practical: Measuring Enzyme Activity
• Biological Membranes
  • Cell Surface Membrane, Structure & Permeability
  • Diffusion & Facilitated Diffusion
  • Active Transport
  • Endocytosis & Exocytosis
  • Osmosis and its effects on cells
  • Investigating Water Potential

3. Exchange & Transport

• Exchange Surfaces
  • Features of Exchange Surfaces
  • Mammalian Gas Exchange System & Ventilation
  • Spirometers
  • Gas Exchange in Fish & Insects
• Transport in Animals
  • Need for Transport Systems
  • Circulatory Systems
  • Blood Vessels, Tissue Fluid, Mammalian Heart, The Cardiac Cycle
  • Heart Activity: Initiation & Control, ECGs
  • Haemoglobin's role
• Transport in Plants
  • Transport systems: Xylem & Phloem
  • Transpiration & Translocation
  • Adaptations of Xerophytic & Hydrophytic Plants

4. Biodiversity, Evolution & Disease

• Communicable Diseases & Immune System
  • Pathogens, Plant Defenses
  • Immune Responses: Non-specific & specific
  • Types of Immunity & Vaccination Principles
• Biodiversity
  • Measuring Biodiversity: Species Richness & Evenness
  • Methods of Maintaining Biodiversity
• Classification & Evolution
  • Classification Systems
  • Evidence and Mechanisms of Evolution

5. Communication, Homeostasis & Energy

• Communication & Homeostasis
  • Thermoregulation
• Excretion
  • Structure and function of Liver and Kidneys
  • Osmoregulation
• Neuronal & Hormonal Communication
  • Neurones and nerve impulse transmission
  • Synaptic Transmission
  • Endocrine System
• Plant & Animal Responses
  • Plant Hormones & Responses
  • Nervous System in Mammals
  • Factors affecting heart rate
• Photosynthesis & Respiration
  • Photosynthesis: Light-dependent & independent stages
  • Respiration: Aerobic & Anaerobic, Energy Yield

6. Genetics, Evolution & Ecosystems

• Cellular Control
  • Gene Mutations & Control
• Patterns of Inheritance
  • Inheritance Patterns: Monohybrid & Dihybrid crosses
  • Hardy-Weinberg Principle
  • Artificial Selection
• Manipulating Genomes
  • Techniques such as PCR, Electrophoresis
• Cloning & Biotechnology
  • Natural & Artificial Cloning
  • Biotechnological Uses of Microorganisms
• Ecosystems
  • Biomass Transfer, Nitrogen & Carbon Cycles
  • Succession
• Populations & Sustainability
  • Conservation and Human Impact

Additional Resources

• Revision notes, exam questions, and past papers available for better preparation and understanding.

Related Links

• A Level Biology resources are available for different exam boards like AQA, Cambridge, and Edexcel.