Plant Nutrition

This lesson covers: 

1. What photosynthesis is
2. The requirements for photosynthesis
3. Plant adaptations for photosynthesis

Photosynthesis

Photosynthesis is the process that plants use to make their own food.

Animals gets their energy from the food they eat but plants make glucose using energy from light.

It happens in the chloroplasts and the glucose they make is used for growth, among various other life processes.

What does a plant need for photosynthesis?

A plant needs four things to be able to photosynthesis.

1. Light energy - This is usually provided by sunlight.
2. Carbon dioxide - This diffuses into the leaves from the air.
3. Water - This is absorbed by the roots and transported to leaves.
4. Chlorophyll - This is a green pigment found in chloroplasts that absorbs light energy.

The photosynthesis equation

The word equation for photosynthesis is:

Chlorophyll uses light energy to convert carbon dioxide and water into glucose and oxygen.

Plant adaptations for photosynthesis

Plants are adapted to make photosynthesis as efficient as possible.

Leaf adaptations

Leaves are adapted to maximise photosynthesis.

1. Leaves have a large surface area to absorb light.
2. Leaves are thin to provide a short diffusion distance for gases.
3. Palisade cells have lots of chloroplasts.
4. Stomata allow carbon dioxide to enter the leaf and oxygen to exit.
5. Veins deliver water to leaf cells.

Root adaptations

Roots are adapted to maximise absorption.

• Root hair cells provide a large surface area for absorption.
• Water is absorbed by the roots and is used for photosynthesis.
• Mineral ions are absorbed with the water and are needed to keep the plant healthy.