1. Assign Yourself: Photosynthesis pg
222- 227
• Do Now:
• 1. How was your break?
• 2. How do you think you did in biology for
semester 1?
• 3. Will you change anything for semester 2?
3. How much light energy from the Sun
hits Earth every day?
A) Half as much energy as humanity
uses every day
B) Twice as much energy as
humanity uses every day
C) 10 times as much energy as
humanity uses every day
D) 20,000 times as much energy as
humanity uses every day
4. What is photosynthesis?
• The process that plants (and some protists and
bacteria) use to convert light energy from the sun
into chemical energy (glucose and other
carbohydrates).
5. What are the reactants and products?
- Photosynthesis requires carbon
dioxide, water, and light.
- Photosynthesis produces
oxygen and glucose.
6. Where does photosynthesis happen?
• Inside the chloroplasts, in the leaf cells of plants
• Inside the chloroplasts of protists like algae
• Inside some bacteria
7. How are the parts of a leaf involved?
• Stomata (holes in the leaf):
–Let carbon dioxide in
–Let oxygen out
• Guard cells open and close the stomata
8. How are the parts of a leaf involved?
• Xylem (cells like pipes in
the stems and veins of
leaves) carry water from
the roots to the leaf
• Phloem (cells like pipes in
the stems and veins of
leaves) carry glucose
away from the leaves to
the rest of the plant.
9. What is chemosynthesis?
• The process that some organisms (mostly
archaebacteria) use to convert chemical energy
from inorganic compounds (compounds without
carbon) into glucose and other organic compounds.
• This is how ancient autotrophs survived before
photosynthesis evolved.
10. Processing Piece
• Draw a picture of a leaf. Show how the reactants
and products of photosynthesis go into and out of
the leaf.
11. Sample Questions:
You fill two test tubes filled with water. Each contains a
water plant called Elodea. You put test tube A in the
dark, and leave test tube B in the sunlight. After 2 days,
you measure the amount of oxygen and carbon dioxide
in the water of both tubes.
1) Draw a picture of this set up.
2) Which test tube will undergo photosynthesis?
3) Will that test tube use up oxygen, or produce it?
4) Will that tube use up carbon dioxide, or produce it?
5) Which test tube will have more oxygen?
6) Which test tube will have more carbon dioxide?
