Year 1 · Plants and animals · Section 1.5
Making food
Substances and energy
Plants make energy-rich substances that are important for growth and development. They do not create energy: they use light energy to make these substances. Humans and other animals obtain nutrients and energy by eating plants or animals that have eaten plants.
Glucose
During photosynthesis, a plant makes glucose, an energy-rich sugar. Glucose can be used to make other substances and supports plant growth and development.
Photosynthesis
Photosynthesis is the process in which a plant makes glucose and oxygen using water, carbon dioxide and light energy. It takes place in green parts of plants, especially the leaves.
The plant takes up water from the soil and carbon dioxide from the air, and uses energy from sunlight.
Why photosynthesis matters
Photosynthesis is essential to much of life on Earth. It supplies:
- Glucose: An energy source and starting material for making other substances in plants.
- Oxygen: Needed for respiration by humans and many other organisms.
Edible plant parts
Humans eat different parts of plants:
- Fruits: Apples and tomatoes.
- Seeds: Cereal grains and rice.
- Roots: Beetroot and carrots.
- Stems: Asparagus; celery is commonly grouped here in everyday descriptions, although the part eaten is mainly a leaf stalk.
- Leaves: Lettuce and spinach.
Glossary
- Photosynthesis
- The process in which plants use water, carbon dioxide and light energy to make glucose and oxygen. It occurs in green parts, especially leaves.
- Glucose
- An energy-rich sugar made during photosynthesis. It supplies energy through respiration and is a starting material for making other substances.
- Nutrients
- Substances needed for growth, repair and energy supply, including carbohydrates, proteins, fats, vitamins, minerals and water. Not all nutrients supply energy.