Name___________________________________________________ Date_____________ Period_______
Photosynthesis: Making Energy
Chloroplasts
Photosynthesis is a process in which sunlight energy is used to make
glucose. The site of photosynthesis is in the chloroplast – an organelle
found in the leaves of green plants. The main functions of chloroplasts are
to produce food (glucose) during photosynthesis, and to store food
energy. Chloroplasts contain the pigment,
chlorophyll
. Chlorophyll absorbs
most of the colors in the color spectrum, and reflects only green and
yellow wavelengths of light. This is why we see leaves as green or yellow –
because these colors are reflected into our eyes.
1. What is photosynthesis? ______________________________________________________
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2. Where does photosynthesis occur? ______________________________________________
3. What are chloroplasts and where are they found? ___________________________________
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4. What are the two main functions of chloroplasts? ___________________________________
5. Why doe most leaves appear green? _____________________________________________
6. What is the primary pigment found in the chloroplast? ________________________________
Photosynthesis
Glucose is another name for sugar. The molecular formula for glucose is C6H12O6. Plants make sugar by
using the energy from sunlight to transform CO2 from the air with water from the ground into glucose.
This process, called photosynthesis occurs in the chloroplast of the plant cell. During this process,
oxygen (O2) is created as a waste product and is released into the air for us to breath. The formula for
photosynthesis is:
(reactants) (products)
CO2 + H2O + sunlight ----> C6H12O6 + O2
This formula says that carbon dioxide + water molecules are combined with the energy from sunlight to
produce sugar and oxygen. The reactants in photosynthesis (what is used) are CO2, water and sun. The
plant gets water from the ground through its roots. The plant collects carbon dioxide from the air. Much
of the carbon dioxide comes from living organisms that exhale (breath it out) it, but some also comes
from factory smokestacks and car fumes.
7. What is the formula for photosynthesis? __________________________________________
8. What three things are used to make glucose in photosynthesis? _________________________
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