Photosynthesis

How do we grow a plant? But is that all????

Plants need to do Photosynthesis Chlorophyll inside

What you don’t see… Thylakoid: individual membrane- bound compartments where photosynthesis actually occurs (contain the photosynthetic pigments) Granum: stacks of thylakoids

And Cholorophyll – pigment molecules that absorb light energy (photons) Sunlight (light Energy) Water H 2 O Carbon Dioxide CO 2

Photosynthesis- what goes in and what comes out? Sunlight (Light Energy) Water H 2 O Carbon Dioxide CO 2 Glucose C 6 H 12 O 6 Oxygen O 2

Photosynthesis Let’s write the chemical equation on the board!! Let’s write the chemical equation on the board!! What are the reactants, What are the products? What are the reactants, What are the products? What type of energy transformations are going on? What type of energy transformations are going on? –Light Energy into Chemical Energy

Reaction CO 2 + H 2 O + light  O 2 + C 6 H 12 O 6 CO 2 + H 2 O + light  O 2 + C 6 H 12 O 6 But it’s not balanced But it’s not balanced 6 CO H 2 O + light  6 O 2 + C 6 H 12 O 6 6 CO H 2 O + light  6 O 2 + C 6 H 12 O 6 Reactants Products

Photosynthesis has an “opposite” reaction… ALL cells must perform this reaction ALL cells must perform this reaction –(not like photosynthesis that only occurs in autotrophs) –Occurs in Mitochondria –It’s why we breathe In fact the name we give to breathing is named after this cellular process In fact the name we give to breathing is named after this cellular process –Any guesses???

Cell Respiration Glucose C 6 H 12 O 6 Oxygen O 2 Carbon Dioxide CO 2 Water H 2 O Energy

Reaction Let’s draw the chemical formula on the board!! Let’s draw the chemical formula on the board!! What are the reactants, What are the products? What are the reactants, What are the products? What type of energy transformations are going on? What type of energy transformations are going on? –Chemical Energy (Food) into Chemical Energy (ATP)

Are you cellular respirating now? How do you know???

Is anyone willing to show us their gas? Is anyone willing to show us they give off water? Is anyone willing to show us they give off water? Let’s DO THIS!!! Let’s DO THIS!!!

Let’s look at this reaction: O 2 + C 6 H 12 O 6 CO 2 + H 2 O + ATP +heat But this equation IS NOT BALANCED!!! If ATP’s chemical formula is C 10 H 16 N 5 O 13 P 3 what is missing??? If ATP’s chemical formula is C 10 H 16 N 5 O 13 P 3 what is missing???

To make ATP from glucose and oxygen, a LOT of other molecules help out. From the diagram, can you find a source for ATP’s nitrogen and phosphorus atoms?? What about those extra C’s, O’s and H’s???

Don’t worry, you can learn that part of cellular respiration on your own by reading Ch. 9, or take A.P. Biology next year! Let’s continue with our notes….

Two Types of Respiration You are currently taking in oxygen and burning sugars within the mitochondria to release chemical energy. You are currently taking in oxygen and burning sugars within the mitochondria to release chemical energy. This process is also known as Aerobic Respiration. Why? This process is also known as Aerobic Respiration. Why? –Because Oxygen is present which allows your cells to burn glucose into energy much more efficiently.

What would happen if your cells were deprived of oxygen?? Would they still be able to burn glucose to make energy?? YES!! Anaerobic Respiration Anaerobic Respiration –What does anaerobic mean? NO OXYGEN PRESENT NO OXYGEN PRESENT Ex: Fermentation in the body cells Ex: Fermentation in the body cells –Long distance runners often create an anaerobic environment for their cells Not a very energy efficient process & a bad side effect is produced: Not a very energy efficient process & a bad side effect is produced: Lactic Acid Lactic Acid

A different example of fermentation Breweries rely on this process: Breweries rely on this process: –Yeast cells need energy to survive, so they will breakdown sugars in anaerobic conditions and a byproduct is alcohol. –How do you know CO 2 is produced?

Fermentation Basics Anaerobic Anaerobic Animals produce lactic acid and CO 2 Animals produce lactic acid and CO 2 Plants produce ethyl alcohol and CO 2 Plants produce ethyl alcohol and CO 2

Efficiency of Types of Cell Respiration Aerobic respiration yields at least 36 ATP Aerobic respiration yields at least 36 ATP Anaerobic nets a measly 2 ATP Anaerobic nets a measly 2 ATP

Let’s see what you know

Muscle cells require more energy than do most other cells. Which organelles would you expect to find in greater abundance in muscle cells than in most other cells? 1.Cilia 2.Mitochondria 3.Ribosomes 4.Chloroplasts

Which of these processes results in carbon dioxide production? 1.Osmosis 2.Respiration 3.Evaporation 4.Photosynthesis

Some organisms that live in the intestines of cows do not require oxygen to survive. Which of the following best describes the process by which these organisms obtain energy? 1.Osmosis 2.Mitosis 3.Cellular respiration 4.Fermentation