Photosynthesis

Refresher Question

What is a leaf’s main function?

Make food! PHOTOSYNTHE

SIS

Refresher Question

What plant structure do you see here:

http://www.botgard.ucla.edu/html/botanytextbooks/generalbotany/images/typesofroots/Sonchusroots.jpg

ROOT

Refresher Question

What is the green pigment that captures light called?

Chlorophyll

Refresher Question

What is the cell organelle that contains chlorophyll called?

Chloroplast

http://www.cbs.dtu.dk/staff/dave/roanoke/chloroplast.gif

Plant Video

National Geographic Video

PhotosynthesisPlants use energy from sunlight to make food

from carbon dioxide and water.

6CO2 + 6H2O Sunlight C6H12O6 + 6O2Chlorophyll

Chlorophyll Green ColorPart of the ChloroplastsCaptures sunlight

http://my.hrw.com/apps/alchemy/editors/viewers/popup_viewer.html

Plant Puzzler

What is the energy source that drives photosynthesis?

SUN

Sugar (Glucose)C6H12O6 6 Carbon, 12 Hydrogen, 6 Oxygen

Glucose is stored energyplants use for food

Made from CO2, H2O, Sunlight and chlorophyll

Plant Puzzler

The kind of food produced directly from photosynthesis is __________?

Sugar = Glucose = C6H12O6

Gas Exchange in LeavesCuticle: waxy covering that protects plant

How does gas “break through” that tough barrier?

Stoma! (plural= stomata)an opening in a leaf or stem that allows gas exchange

Each stoma has 2 Guard CellsGuard Cells open or close stoma

Closed stoma = no gas exchange Open stoma = gas exchange

Carbon Dioxide (CO2), Oxygen (O2), and Water Vapor (H2O)

http://my.hrw.com/la/eolit05/nsmedia/eolit05_image_gallery.html

Plant Puzzler

An opening in a plant that allows for gas exchange is called a __________?

What gases are transported through the stoma? Stoma

CO2, O2, H2O

Question #1Put a plant under a dark box. Is this plant undergoing photosynthesis? Why or why not?

http://www.fightingquaker.com/jaropt/table_plant.jpg

http://homepage.eircom.net/~pakform/bse_007-3.gif

Question #2Describe what you think will happen

to the life seen here (and on Earth), after a meteor blackened the sky so that no sun could shine through?

Question #3

Are the leaves you see here undergoing photosynthesis? Why or why not?

Pretend that the branch is still attached to the living tree.

Question #4

If you and a large tree were locked in an airtight compartment, with plenty of food, water, and nutrients, could you survive? Explain your answer.