Transcript The Cell Cycle & Asexual Reproduction

Refresher Question
 What is a leaf’s main function?
Make food!
PHOTOSYNTHESIS
Refresher Question
 What plant structure do you see here:
http://www.botgard.ucla.edu/html/botanytextbooks/generalbotany/images/typesofroots/Sonchusroots.jpg
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
Photosynthesis
 Plants use energy from sunlight to make food from
carbon dioxide and water.
6CO2 + 6H2O
Sunlight
Chlorophyll
 Chlorophyll
 Green Color
 Part of the Chloroplasts
 Captures sunlight
C6H12O6 + 6O2
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 energy
 plants 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 Leaves
 Cuticle: 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 Cells
 Guard 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 #1
 Put a plant under a dark box.
 Is this plant undergoing photosynthesis?
Why or why not?
http://homepage.eircom.net/~pakform/bse_007-3.gif
http://www.fightingquaker.com/jaropt/table_plant.jpg
Question #2
 Describe 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.