Bioenergetics – GCSE AQA Higher Biology revision notes

What this topic covers

Bioenergetics has 2 subtopics:

• Photosynthesis
• Respiration

Bioenergetics lessons by subtopic

13 lessons, grouped by subtopic.

Photosynthesis

• The Photosynthesis Equation and Chemical Symbols: Learn the word equation for photosynthesis, understand the chemical symbols CO2, H2O, O2 and C6H12O6, and explore how photosynthesis is an endothermic reaction that transfers energy from light to chloroplasts.
• How Plants Use Glucose for Energy and Storage: Explore how plants use glucose produced in photosynthesis for immediate energy through respiration and long-term storage as starch and oils, understanding the importance of these processes for plant survival.
• Building Plant Structures with Glucose: Discover how plants convert glucose into cellulose for strengthening cell walls and amino acids for protein synthesis, including the role of nitrate ions from soil in protein production.
• Measuring and Graphing Photosynthesis Rates: Learn how to measure photosynthesis rates, interpret and create graphs, and understand the key factors that affect photosynthesis speed including temperature, light intensity, carbon dioxide concentration, and chlorophyll amount.
• Limiting Factors in Photosynthesis (Higher Tier): Explore how multiple factors interact to limit photosynthesis, analyze complex graphs with multiple variables, understand the inverse square law with light intensity, and examine the economics of optimizing greenhouse conditions for maximum photosynthesis rates.

Respiration

• What is Metabolism?: Understanding metabolism as the sum of all reactions in cells and how respiration provides energy for metabolic processes.
• Building Large Molecules from Small Ones: How glucose is converted to starch, glycogen and cellulose, and how lipids and proteins are synthesised from smaller molecules.
• Breaking Down Molecules and Building Blocks: The breakdown of excess proteins to form urea and understanding the importance of building blocks in synthesis and breakdown of biological molecules.
• Introduction to Cellular Respiration: Learn what cellular respiration is, why organisms need energy, and understand the key characteristics of this vital process including its exothermic nature and continuous occurrence in living cells.
• Aerobic Respiration: Explore aerobic respiration in detail, including the word equation and chemical symbols, and understand how oxygen is used to completely break down glucose for maximum energy transfer.
• Anaerobic Respiration and Fermentation: Compare anaerobic respiration to aerobic respiration, learn the equations for anaerobic respiration in muscles and yeast cells, and discover the economic importance of fermentation.
• How the Body Responds to Exercise: Learn how the human body reacts to increased energy demands during exercise, including changes to heart rate, breathing rate and breath volume to supply muscles with more oxygenated blood.
• Anaerobic Respiration and Recovery: Understand what happens when insufficient oxygen is supplied during exercise, including anaerobic respiration, lactic acid buildup, oxygen debt, muscle fatigue, and how the body recovers after exercise.

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