4.1 photosynthesis
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4.1 Photosynthesis. 7.1.d Students know that mitochondria liberate energy for the work that cells do and that chloroplasts capture sunlight energy for photosynthesis. Sources of Energy. ALL cells need energy! - PowerPoint PPT PresentationTRANSCRIPT
4.1 Photosynthesis
7.1.d Students know that mitochondria liberate energy for the work that cells do and that chloroplasts capture sunlight energy for photosynthesis.
Sources of Energy• ALL cells need energy!• Photosynthesis- process by
which a cell captures energy in sunlight and uses it to make food
• Key Concept: “Nearly all living things obtain energy either directly or indirectly from the energy of sunlight captured during photosynthesis."
• Autotroph- organism that makes its own food
• Heterotroph- organism that cannot make its own food
Sources of Energy
The Two Stages of Photosynthesis
Key Concept: “During photosynthesis, plants and some other organisms use energy from the sun to convert carbon dioxide and water into oxygen and sugars.”
Oxygen exits through the stomata on the underside of the leaf.
Carbon dioxide enters the leaf through openings called stomata
Water inters the plant through roots and moves upward to the leaves
Stage 2The captured light energy is used to produce sugars and oxygen from water and carbon dioxide.
Sugar produced are used by the plant cells for energy
The Two Stages of Photosynthesis• Photosynthesis takes place in 2 stages: capturing
sunlight and producing sugar• Pigments- colored chemical compounds that absorb
light• Chlorophyll- main photosynthetic pigment in
chloroplasts• Chloroplasts- are the green organelles in plant cells
that give the plant its color• Chlorophyll is like solar “cells” or cells that capture the
energy in light in a calculator• The captured light is used to power the second stage
The Two Stages of Photosynthesis• 2 raw materials needed for stage 2 are water and carbon
dioxide• Roots absorb water, water then moves up through stem to the
leaves, carbon dioxide enters through the stomata• Once the water and carbon dioxide are in the leaf they move
into the chloroplasts• Stomata- small openings on the underside of leaves• In the chloroplasts the water and carbon dioxide go through
chemical reactions• These chemical reactions are powered by the energy
captured in stage 1• One important byproduct of this chemical reaction in oxygen
and exits through the stomata
The Two Stages of Photosynthesis• The Photosynthesis equation:
6CO2 + 6H2O → C6H12O6 + 6O2
Carbon Dioxide
Oxygen
Water
SugarLight energy
The Photosynthesis Process Activity
• Click the Active Art button to open a browser window and access Active Art about the photosynthesis
process.
How does the sun supply living things with the energy they need?What happens during the process of photosynthesis?
Review