Photosynthesis and Respiration

4th Grade Science

How Are Plants and Animals Different?

• Animals cannot make

their own food.

• Plants can make their own food.

It’s question time!

What is the process by which plants make food?

* Photosynthesis

Photosynthesis is the process by which plants make food. A green plant makes food using light energy. Green plants get light energy from the sun.

What part of the plant produces food?

Here comes a hint!

In most plants the leaves are the special parts where the most food is made.

Leaves contain a chemical called chlorophyll. Chlorophyll is the green matter in plants that traps light energy to produce food.

Plants use water and carbon dioxide to make food.

Water is taken from the soil by the roots and travels up the stems to the leaves. Carbon dioxide is taken from the air. Air enters the plant through small openings (stomata) in leaves.

STOMATA

Tiny openings on the underside of the leaf. Stomata is similar to a human nose. Stomata breathes in carbon dioxide and breathes out oxygen. The human nose breathes in oxygen and breathes out carbon dioxide.

Plants store extra food in the forms of sugar and starch.

Sugar – sweet grapes

Starch – corn

Pop quiz!

Why is energy needed by plants and animals?

Energy is needed for growth, repair of tissues, movement, warmth, and all other body functions.

All living things need energy. Energy comes from food made by plants. Oxygen combines

with food and energy is released.

ALL LIVING THINGS NEED ENERGY!

PHOTOSYNTHESIS is the process by which green plants get light energy from the sun. This energy is collected in the plant leaves as chlorophyll.

Chlorophyll helps the plant produce food along with water and carbon dioxide.

Once again……………