Learn: Photosynthesis

Welcome!Today we'll explore photosynthesis, the process plants use to make their own food. This is crucial for life on Earth as it provides energy for almost all living organisms. Let's dive in!

What is Photosynthesis?Photosynthesis is a process where plants convert light energy, carbon dioxide, and water into glucose and oxygen. It happens in the chloroplasts of plant cells and relies on a green pigment called chlorophyll.

Photosynthesis EquationThe word equation for photosynthesis is:Carbon dioxide + Water → Glucose + Oxygen (in the presence of light and chlorophyll).This shows how plants use sunlight to create energy-rich glucose while releasing oxygen as a by-product.

Where Does Photosynthesis Occur?Chloroplasts in plant cells are the site of photosynthesis. They contain chlorophyll, which captures light energy. Photosynthesis mainly happens in the palisade layer, located near the upper surface of leaves.

Leaf Structure and AdaptationsLeaves are specially adapted for photosynthesis. They have a large surface area to absorb more light, thin structures for easy gas exchange, and stomata (tiny openings) for carbon dioxide intake.

Limiting FactorsThe rate of photosynthesis can be affected by limiting factors. These include:Light intensity: More light increases the rate until a maximum point.Carbon dioxide concentration: Higher levels can boost photosynthesis.Temperature: Too high or low temperatures can slow down enzyme activity.

Investigating PhotosynthesisWe can test for photosynthesis by checking for starch in a leaf. This involves boiling the leaf, placing it in ethanol to remove chlorophyll, and then adding iodine. A blue-black colour indicates the presence of starch.

Review Time!Great work! You've learned about photosynthesis, its equation, adaptations, and limiting factors. Let's review with some final questions.