Topic 1: Key concepts in biology – GCSE Edexcel Higher Biology revision notes

What this topic covers

Topic 1: Key concepts in biology has 5 subtopics:

• Cell structure
• Principles of organisation
• Animal tissues, organs and organ systems
• Transport in cells
• Biological molecules and food tests

Topic 1: Key concepts in biology lessons by subtopic

25 lessons, grouped by subtopic.

Cell structure

• Understanding Cell Types: Eukaryotes vs Prokaryotes
• Comparing Animal and Plant Cell Structures
• Structure and Function Relationships in Cells
• Specialised Cells in Animals: Explore how sperm cells, nerve cells and muscle cells are specialised for their specific functions, including their structural adaptations and roles in different organ systems.
• Specialised Cells in Plants: Investigate the structure and function of root hair cells, xylem and phloem cells, and how their specialisations enable them to carry out specific roles in plant tissues and organs.
• Linking Structure to Function: Develop skills to analyse and explain how the structure of different specialised cells relates to their function within tissues, organs, organ systems and whole organisms.
• Cell Differentiation: Animal vs Plant Cells
• Development of Microscopy Techniques
• Magnification Calculations
• Setting up sterile cultures and bacterial growth
• Measuring and calculating bacterial populations

Principles of organisation

• From Cells to Organisms

Animal tissues, organs and organ systems

• The digestive system and enzymes: Understanding how the digestive system works as an organ system, the nature of enzymes and how they catalyse reactions using the lock and key model
• Digestive enzymes and their actions: Learning about the different types of digestive enzymes, where they are produced, what they break down and how their products are used in the body
• The role of bile in digestion: Understanding how bile is produced, stored and used to help digest fats by neutralising acid and emulsifying lipids

Transport in cells

• What is diffusion and what affects its rate?
• Surface area to volume ratio and single-celled organisms
• Exchange surfaces in multicellular organisms
• Understanding Osmosis
• Measuring and Calculating Water Movement
• Graphing Osmosis Results
• Understanding Active Transport and Comparing Cell Transport Methods
• Active Transport in Action: Plants and Animals

Biological molecules and food tests

• Digestive enzymes and biological molecules: Understanding how the digestive system works as an organ system, the nature of enzymes and how they catalyse reactions using the lock and key model
• Food tests and calorimetry: Use Benedict's solution, iodine solution, biuret reagent and emulsion tests, then link food-energy comparisons to calorimetry.

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More in this course

Go back to the full GCSE Edexcel Higher Biology topic list, or practise this topic with past-paper questions.