Learn: Photosynthesis and Leaf Structure

Welcome!Today we'll explore photosynthesis, a vital process that plants use to produce energy. We'll also examine the structure of leaves and their role in this process.

What is Photosynthesis?Photosynthesis is the process by which plants make their own food using sunlight, carbon dioxide, and water. It produces glucose (a sugar) and oxygen, which are essential for life on Earth.

The Photosynthesis EquationThe word equation for photosynthesis is: carbon dioxide + water → glucose + oxygen. This reaction occurs in the chloroplasts of plant cells, using a green pigment called chlorophyll.

Leaf Structure and AdaptationsLeaves are adapted to maximise photosynthesis. They have a large surface area to absorb sunlight, and their thin shape allows gases to move in and out easily.

Main Parts of a LeafThe key parts of a leaf include the cuticle (waxy layer preventing water loss), epidermis (outer protective layer), palisade layer (cells with lots of chloroplasts), and stomata (small openings for gas exchange).

Limiting Factors of PhotosynthesisPhotosynthesis depends on three main factors: light intensity, carbon dioxide concentration, and temperature. If any of these are too low, photosynthesis slows down.

Investigating PhotosynthesisScientists use experiments to study photosynthesis. For example, they might test a leaf for starch using iodine. If starch is present, the leaf will turn blue-black.

Review Time!Great work! You've learned about photosynthesis, leaf structure, and the factors affecting this process. Let’s test your understanding with a few questions.