Presentation on theme: "March 4, 2013Q-2 Pg. Daily Goal: We will be able to explain why leaves on trees in Alaska might look different than leaves in Costa Rica. Homework: Revise."— Presentation transcript:
March 4, 2013Q-2 Pg. Daily Goal: We will be able to explain why leaves on trees in Alaska might look different than leaves in Costa Rica. Homework: Revise your test. Science Starter: 1.Where do plants get energy from? 2.Where do animals get energy from? 3.Name one rainforest plant adaptation that you learned about from your plant packet.
Table Group Point! Where is Costa Rica?
Table Group Point! Who can guess what Ms. Petersen’s favorite flower is?
Table Group Point! Do trees have a stem? (You have to explain your answer.)
Table Group Point! 3 Tell me 3 things you know about leaves.
Function of leaves Leaves trap light energy for photosynthesis. Leaves produce sugar from photosynthesis Leaves exchange gases. Which gasses do leaves exchange? oxygen and carbon dioxide Which gas do leaves produce? oxygen
Leaf Structure Leaf Width: Wider leaves catch more light energy. Thin leaves help get carbon dioxide from bottom to top of leaf quickly for photosynthesis.
Pros and Cons of Big Leaves Pro of big leaves: Bigger leaves can do more photosynthesis Con of big leaves: Bigger leaves also lose more water through transpiration.
Pine trees live in places that are cold and dry. Costa Rica is a rainforest. It has wide-leaved plants. Why does that make sense?
Gas exchange Leaves are designed to let carbon dioxide to get to the layer of chlorophyll at the top of the leaf. They have small holes called stomata on the under surface.
Stomata – small openings in leaves that open and close at different times of the day to let in carbon dioxide and let oxygen out When it is light the plant needs CO 2 for photosynthesis so the stoma open. Stomata
Table Group Point! Would stomata be more likely to be open during the day or at night? (Be prepared to explain your answer.)