Life Support for Life Support for PlantsPlants

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Basic Needs of PlantsBasic Needs of Plants

AirAirNutrientsNutrientsWaterWaterSoilSoil

Why do plants need air?Why do plants need air?

There is carbon dioxide in the There is carbon dioxide in the air. Leaves take in this carbon air. Leaves take in this carbon dioxide.dioxide.

Carbon dioxide is one of the Carbon dioxide is one of the two main materials plants use two main materials plants use to make food.to make food.

Why do plants need nutrients?Why do plants need nutrients? Just as animals need nutrients Just as animals need nutrients

(vitamins and minerals) for growth, (vitamins and minerals) for growth, so do plants.so do plants.

Soil provides plants with the Soil provides plants with the nutrients they need to survive.nutrients they need to survive.

Plants cannot survive in soil that Plants cannot survive in soil that doesn’t have the necessary nutrients.doesn’t have the necessary nutrients.

What about water?What about water?

Plants get water from rain.Plants get water from rain.Some of the water is absorbed Some of the water is absorbed

through the plant leaves.through the plant leaves.Most is absorbed by the roots.Most is absorbed by the roots.

Necessary LightNecessary Light

No plant can live in total No plant can live in total darkness.darkness.

Some plants, however, may Some plants, however, may grow better in shaded areas.grow better in shaded areas.

PhotosynthesisPhotosynthesis Scientific name for the process by Scientific name for the process by

which a plant makes its own foodwhich a plant makes its own food ““Photo” means “Light”Photo” means “Light” ““Synthesis” means “Putting Together”Synthesis” means “Putting Together” Plants make food from light energy Plants make food from light energy

combined with carbon dioxide and combined with carbon dioxide and water.water.

How does photosynthesis work?How does photosynthesis work? Light + Carbon Dioxide + WaterLight + Carbon Dioxide + Water Light is trapped by the chlorophyll. Light is trapped by the chlorophyll. Leaves take in carbon dioxide.Leaves take in carbon dioxide. Roots take in water.Roots take in water. Water travels to leaves.Water travels to leaves. In the leaves, sugar is formed.In the leaves, sugar is formed. Oxygen is then released into the air by Oxygen is then released into the air by

the leaves.the leaves.

Plant AdaptationsPlant Adaptations Water plants grow from soil below the Water plants grow from soil below the water, with stems growing toward surfacewater, with stems growing toward surface

Vines grow on forest floors, but have Vines grow on forest floors, but have stems climbing and clinging to other stems climbing and clinging to other plants or objects for support and to get plants or objects for support and to get sunlightsunlight

Desert plants have thick stems that can Desert plants have thick stems that can store water for long periods; also have store water for long periods; also have roots near surface, to absorb water quicklyroots near surface, to absorb water quickly