Page 2: Cell Transport and Division

This chapter focuses on cellular transport mechanisms and division processes, essential topics in GCSE cell biology exam questions and answers PDF. The content covers diffusion, osmosis, and active transport, along with detailed information about stem cells.

Definition: Diffusion is the net movement of particles from an area of high concentration to an area of lower concentration.

Example: Exchange surfaces like villi in the small intestine demonstrate specialized adaptations for efficient absorption.

Highlight: The section on stem cells compares adult, embryonic, and plant meristem cells, discussing their advantages and disadvantages.

Vocabulary: Active Transport - movement of particles against a concentration gradient using energy Meristem - plant tissue where cell division occurs

Page 3: Enzymes and Plant Organization

This section details enzyme function and plant organization, key topics in bioenergetics AQA GCSE. It covers the lock and key theory, enzyme denaturation, and plant tissue structure.

Definition: The lock and key theory explains how enzymes work by having a specific active site that only fits particular substrate molecules.

Example: Stomata and guard cells demonstrate how plants control water loss through specialized structures.

Highlight: The transpiration stream shows how water moves through a plant, pulled up from roots through the xylem.

Vocabulary: Denaturation - the process where proteins lose their shape and function Translocation - movement of dissolved sugars through phloem

Disease Transmission

The fifth page focuses on disease spread mechanisms, particularly relevant for gcse biology revision notes pdf.

Example: Measles spreads through respiratory droplets, while HIV transmits through body fluid exchange.

Highlight: Plant diseases like TMV can significantly impact photosynthesis efficiency.