Photosynthesis and Respiration 1 Plants are Autotrophs An

Photosynthesis and Respiration 1

Plants are……. Autotrophs ►An autotroph is an organism that makes its own food from inorganic substances. It is then eaten by a consumer if it is a plant for example. 2

During photosynthesis plants use energy from the sun to convert (change) carbon dioxide and water into oxygen and sugars 3

2 Stages of Photosynthesis: • 1 – Energy in sunlight is captured. • In plants, the energy is captured in the leaves and other green parts of the plant. 4

• Chloroplasts in the plant are responsible for plants green color. • Colored pigments that make the plant green are the chemicals that capture the sunlight. 5

Comparison Where it takes place Baking a cake Photosynthesis ___________ 6

2— Cells use captured energy to produce food (sugar). • The cell needs two raw materials for this stage: Water (H 2 O) and Carbon Dioxide (CO 2) 7

How does a plant get water? üROOTS absorb water from soil. üThe part of the plant that sends this water and other nutrients up the stem to the leaves is the xylem. 8

• Carbon dioxide enters the plant through small openings on the underside of the leaves called stomata. • Stomata • Open-- CO 2 enters • Closed-- O 2 leaves 9

Sun’s Energy: ◊The sun’s energy comes in two forms: light and heat. 1 --Heat energy cannot be captured directly by plants or animals. 2—Light energy can be captured by plants and is used during photosynthesis 10

• Photosynthesis Equation: • CO 2 + H 2 O + Raw materials + = O 2 + C 6 H 12 O 6 products Because water absorbs sunlight, there is only enough light for photosynthesis near the surface or in shallow water. So in water biomes, algae is usually the main producer of energy. 11

• Food spreads out to the leaves, through the phloem which carries food to the plant’s stems and roots. 12