Why Climate Change?

Atmospheric CO2 1955-2014

Average Annual Land & Ocean Surface Temperatures 1850 - 2012

Atmospheric CO2, Ocean CO2, & Ocean pH from 1990 to 2014

The Carbon Cycle

Carbon Movement and Storage

After looking at your pictures…› share what you’ve noticed about where

Carbon is found…› Share what you’ve noticed about how

Carbon moves from place to place…

We are going to focus on some of the natural processes that move Carbon…› Photosynthesis› Cellular Respiration

Elodea / Fish Lab Using Bromothymol Blue is a pH indicator. Review:

› What is pH?› How does the scale work?

BTB gets bluer the more basic a solution is.

When CO2 is in water, it forms Carbonic Acid, H2CO3

We will use BTB as an indicator of CO2

Photosynthesis

Purpose? › Convert light energy into stored chemical

energy (=glucose) that the plant can use

Who does it?› Autotrophs

Where does it happen?› Choloroplasts

Photosynthesis

Chloroplasts

Formula:

6CO2 + 12H20 C6H12O6 + 6O2 + 6H20

Note** water on product side is NEW, formed from different combination of H’s and O’s.

Cellular Respiration

Purpose› Convert stored chemical energy into

useable energy (=ATP)

Who does it?› ALL organisms (even plants!)

Where?› Mitochondria

Formula:

C6H12O6 + 6O2 6CO2 + 6H2O + Heat + ATP

Note: Enzymes

Enzymes involved in both reactions (PS &CR)› Different enzymes = specificity

› Increase speed of chem rxns

› Lower activation energy (so cell won’t fry)

Note: ATP

ATP= chemical energy used to do WORK› Usable Energy stored in bonds (AT-P-P~P) that is

released when bonds are broken

› Used for movement & breakdown of molecules

› Comes from glucose breakdown!

› Energy not recycled, but nutrients and matter are

How does it all fit together?

Go back to your Elodea / Fishy Models. Fix and add to your explanations.

Think back to Food Webs and Pyramids

The Carbon Cycle

An Interesting Connection to Tucker Prairie

Different types of plants “trap” CO2 for photosynthesis in slightly different ways.

At Tucker Prairie, there is competition between these C3 & C4 Plants› C3 Plants trap CO2 with one enzyme

› C4 Plants trap CO2 with two enzymes and require a little bit of extra energy

C3 Plants ~85% of all plants are C3

Examples—rice, wheat, barley, most trees and many grasses› Grasses of Tucker Prairie

Stomata are open during day and closed at night—this is important because they can get CO2 for photosynthesis

Do best in Temperate environments

C4 Plants ~3% of all land plants Examples—corn, sugarcane, and many grasses

› Forbs of Tucker Prairie Stomata are open during day and closed at

night—BUT…stomata can close if the plant is losing too much water during the day.› When stomata close, CO2 concentration in leaves

go down.› Plant can still do photosynthesis because of the 2nd

enzyme Do well in tropical, high heat intensity and

drought conditions

Some pictures…

C3 Pathway

Think back to what we learned about rain at Tucker Prairie…

Which plants have the advantage—› C3 Grasses?

› C4 Forbs?