1. Photosynthesis & Cellular Respiration

2. Photosynthesis Equation
Uses the energy from sunlight to convert water and carbon dioxide into high-energy sugars and oxygen

3. How do plants get energy from light?
From the chlorophyll!!!
A pigment found in plants
They absorb light

4. Through the stoma in their leaves!
How do plants get CO2?
Through the stoma in their leaves!
Opening at the bottom of a leaf that lets CO2 and O2 to diffuse in and out

5. What else do we need for photosynthesis?
Electron carriers!
Sunlight excites electrons in chlorophyll and gives them energy
Need a special carrier for high-energy electrons
NADP+ is an electron carrier

6. Anatomy of a Chloroplast
chlorophyll: pigment inside chloroplasts
thylakoid: saclike membranes (light-dependent reactions)
stack of thylakoids
stroma: area outside thylakoid (light-independent reactions)

7. Photosynthesis

8. Light-Dependent Reaction
Uses ADP+P & NADP+ from the light- independent reactions to carry electrons
6 H2O & sunlight enter the cycle
6 Oxygen exits the cycle
Makes ATP & NADPH

9. Photolysis-happens in Light-Dependent Reaction
Light is absorbed and breaks up water molecules into 3 parts:
Energized electrons
Hydrogen ions (H+)
Oxygen (O2)

10. Light Independent Reaction aka Calvin Cycle
Uses ATP & NADPH from the light- dependent reactions to make high-energy sugars (Glucose)
ATP goes in (gives energy) and NADPH goes in (donates electrons)
6 CO2 enter the cycle
Glucose exits the cycle

11. ADP vs. ATP Cells store and release energy with ATP Store=ADP
Release=ATP

14. What can limit photosynthesis?
Light intensity
Carbon dioxide concentration
Temperature

15. Carbohydrates & Lipids

16. Monomer vs. Polymer
Monomer = 1 unit
Polymer = Many units

17. Carbohydrate Monomer: Monosaccharide Polymer: two kinds
Means “simple sugar”
Ex. Glucose, fructose, galactose
Polymer: two kinds
Disaccharide (2 monosaccharides)
Ex. Sucrose (table sugar), lactose (milk sugar), maltose (malt sugar)
Polysaccharide (3+ monosaccharides)
Ex. Cellulose (fiber), starch (how plants store glucose), glycogen (animal starch), chitin (insect exoskeleton)

18. Function: Provides energy
Carbohydrate
Function: Provides energy
Also can provide structure
2:1 ratio of Hydrogen:Oxygen

19. Lipids Monomer: Glycerol & Fatty acids
Polymer: fats, oils, waxes, steroids, phospholipids
Two types of fats:
Saturated-no double bonds in the fatty acid tails
Unsaturated-at least one double bond in the fatty acid tails
Examples of Fats:
Triglycerides
Sterols-cholesterol & steroids
Phospholipids-cell membrane

20. Lipids Function: long-term energy storage
Insulation, membranes, chemical messengers and waterproofing

21. Cellular Respiration

22. Cellular Respiration
Releases energy by breaking down glucose (or other food molecules) in the presence of oxygen
Aerobic
Responsible for most of our stored energy
All living things do this!

23. Anatomy of Mitochondria
Has two membranes
Cristae-Electron Transport Chain
Matrix-Krebs Cycle

24. Chemical Energy
ATP: adenosine triphosphate – chemical compound used to store & release energy
breaking this bond releases energy
when one P is removed, energy is released
ATP ADP + P

25. Step 1: Glycolysis
One molecule of glucose is broken in ½ making two molecules of pyruvic acid
Release ATP & NADH (notice that it’s not NADPH)

26. Step 2: Krebs Cycle Pyruvic acid is broken down into CO2
Occurs in the matrix
Goes through this cycle twice!
High-energy electrons are picked up by carriers and taken to the Electron Transport Chain

27. Step 3: Electron Transport Chain
Uses high-energy electrons from Krebs Cycle to convert ADP to ATP
Occurs in the cristae!
O2 is the final electron acceptor in the chain-> makes water
Most ATP is made in this step!

28. Photosynthesis vs. Cell Respiration
You decide!

29. Fermentation

30. What happens if we don’t have Oxygen?
Fermentation!
Release energy from food molecules by producing ATP without O2
Anaerobic (without oxygen)
There are 2 main types:
Alcoholic fermentation
Lactic Acid fermentation

31. Alcoholic Fermentation
Yeast and other microorganisms do this
Ethyl alcohol and CO2 as waste
Causes bread dough to rise
Only 2 ATP are made

32. Lactic Acid Fermentation
Converting pyruvic acid into lactic acid
Muscles, pickles, sauerkraut, sour cream, yogurt, cheese & buttermilk
Only 2 ATP are made

33. Let’s compare!
Anaerobic vs Aerobic Respiration
Running discussion