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
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GCSE Edexcel Higher Combined Science Biology · Topic 1 of 9
Topic 1: Key concepts in biology – GCSE Edexcel Higher Combined Science Biology revision notes
Choose a subtopic. Cells, microscopy, enzymes, biological molecules and transport. 22 lessons in 5 subtopics.
Revise Topic 1: Key concepts in biology for GCSE Edexcel Higher Combined Science Biology, including Cell structure and Principles of organisation.
22
Lessons
5
Subtopics
Topic 1: Key concepts in biology lessons by subtopic
22 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
- Specialised Cells in Plants
- Linking Structure to Function
- Cell Differentiation: Animal vs Plant Cells
- Development of Microscopy Techniques
- Magnification Calculations
Principles of organisation
Animal tissues, organs and organ systems
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
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Frequently asked questions
What is Topic 1: Key concepts in biology?
Cells, microscopy, enzymes, biological molecules and transport. 22 lessons in 5 subtopics.
What is osmosis?
Osmosis is the diffusion of water through a partially permeable membrane from a dilute solution to a concentrated solution. The Understanding Osmosis notes cover this in full.
What are specialised cells?
Specialised cells are cells that have developed specific structures and functions to carry out particular roles in multicellular organisms. The Specialised Cells in Animals notes cover this in full.
How do you calculate magnification?
Magnification is calculated with magnification = image size ÷ real size. The Magnification Calculations notes cover this in full.
What is diffusion?
Diffusion is the net movement of particles from high to low concentration. The What is diffusion and what affects its rate? notes cover this in full.
What is an enzyme?
An enzyme is a biological catalyst that speeds up specific chemical reactions in living organisms by lowering the activation energy required. The The digestive system and enzymes notes cover this in full.
What is the function of the cytoplasm?
The cytoplasm is a jelly-like substance where chemical reactions take place and in which organelles are suspended. The Comparing Animal and Plant Cell Structures notes cover this in full.
What is a tissue in biology?
A tissue is a group of cells with similar structure and function working together to perform a specific task. The From Cells to Organisms notes cover this in full.
What is active transport?
Active transport is the movement of substances against a concentration gradient, from low to high concentration, using energy from respiration. The Understanding Active Transport and Comparing Cell Transport Methods notes cover this in full.