Plant Tissues and Their Functions Revision Notes | GCSE OCR Foundation Biology

What this lesson covers

Explore the five main types of plant tissue: epidermal tissue, palisade mesophyll, spongy mesophyll, xylem and phloem, and meristem tissue. Learn how ea...

• Identify the five main types of plant tissues and their locations
• Explain how the structure of each plant tissue relates to its specific function
• Compare the roles of xylem and phloem in plant transport systems
• Describe the function of meristem tissue in plant growth

Key ideas to keep in view

Use this lesson to stay inside B2.2 The challenges of size while connecting the detail back to the wider B2: Scaling up topic.

• B2: Scaling up
• B2.2 The challenges of size
• GCSE OCR Foundation Biology

Lesson notes preview

Read the core explanations from Plant Tissues and Their Functions before testing yourself from memory.

• A single leaf contains millions of cells, yet it works like a perfectly coordinated factory. How does a plant organise all these cells to capture sunlight, transport water, and make food? The secret lies in specialised tissues - groups of cells that have evolved specific structures to do specific jobs.
• Think of it like a school. You wouldn't expect the canteen staff to teach maths, or the teachers to serve lunch. Each group has a specialised role. Plant tissues work the same way - each type has a unique structure that makes it perfect for its function.
• The protective outer layer of cells that covers all plant surfaces, forming a barrier against water loss and pathogens.
• Picture the epidermis as the plant's skin. These cells are tightly packed with waxy coatings to stop water escaping. **Trap**: Many students think epidermis is just for protection - it also controls gas exchange through tiny pores called stomata.
• Tightly packed cells just below the upper epidermis, containing many chloroplasts for maximum photosynthesis.
• These are the plant's solar panels. Palisade cells are tall and thin, packed with chloroplasts, and positioned to catch the most sunlight. Their cylindrical shape means more cells can fit in the same space - maximising light capture.
• Loosely arranged cells with air spaces between them, allowing gases to move freely for photosynthesis and respiration.
• While palisade cells catch light, spongy mesophyll handles gas exchange. The air spaces between cells create highways for carbon dioxide to reach photosynthesising cells and oxygen to escape.
• Plants need a transport system just like we need blood vessels. But plants have two separate networks - one for water going up, one for food going around. This is where structure really shows function.
• Dead, hollow cells with thick walls that transport water and mineral ions from roots to leaves in one direction only.

Continue through the topic

Move to the related lessons or back to the topic page when you need the wider sequence before exam-style practice.