Learn: Photosynthesis

Welcome!I've reviewed your growth areas and created this lesson to help you strengthen your understanding of photosynthesis. Let's explore what it is, how it works, and why it's so important for plants and life on Earth.

What is Photosynthesis?Photosynthesis is the process by which plants, algae, and some bacteria convert light energy from the sun into chemical energy stored as glucose. This process is essential for life on Earth because it provides food and oxygen for living organisms.

The Photosynthesis EquationThe word equation for photosynthesis is: carbon dioxide + water → glucose + oxygen. Plants use sunlight, chlorophyll (a green pigment), and carbon dioxide from the air to produce glucose, which they use for energy and growth.

Where Does Photosynthesis Happen?Photosynthesis happens in the chloroplasts, which are special structures found in plant cells. Chloroplasts contain chlorophyll, the green pigment that absorbs sunlight for energy. Most chloroplasts are found in the leaves of plants.

What Does a Plant Need for Photosynthesis?A plant needs three main things for photosynthesis: sunlight, carbon dioxide, and water. Sunlight provides the energy, carbon dioxide comes from the air, and water is absorbed by the roots from the soil.

How Does Photosynthesis Work?Photosynthesis happens in two stages: the light-dependent reactions and the light-independent reactions. During the light-dependent reactions, sunlight is captured and used to make energy-rich molecules like ATP. In the light-independent reactions, carbon dioxide is used to make glucose.

Limiting Factors of PhotosynthesisThe rate of photosynthesis can be affected by environmental factors. Temperature, light intensity, and carbon dioxide concentration are all limiting factors. If one of these is too low, photosynthesis slows down.

Adaptations of Leaves for PhotosynthesisLeaves are adapted for photosynthesis by being thin and flat, which increases the surface area for light absorption. They also contain many chloroplasts and have stomata that allow gas exchange (carbon dioxide in, oxygen out).

Review Time!Great work! You've learned about photosynthesis, its stages, limiting factors, and leaf adaptations. Now let's test your understanding with a few final questions.