Photosynthesis and Cellular Respiration Chapter 5 Photosynthesis and Cellular Respiration

Energy and Living Things All energy in living systems comes from the sun.

Metabolism Using energy to build molecules Or breaking down molecules for storing energy Includes photosynthesis and cell respiration

Photosynthesis Involves building molecules that store energy Light energy is converted into sugar Autotrophs – organisms that need to make their own food.

Cellular Respiration Converts energy from food to ATP (adenosine triphosphate) Heterotrophs - Organisms that need to consume food

ATP Stores and Releases energy ATP is made up of: 3 phosphates Sugar (ribose) Base (adenine) Energy is stored in P to P bond.

Energy Cycle Energy given off - heat Energy to make ATP: Respiration 1. Aerobic 2. Anarobic ADP

ADP – Adenosine Diphosphate A phosphate is gone. ADP: Adendine Ribose 2 phosphates

You should already know that we turn sugar into ATP in a process called __________________

Where do your cells get ATP?

There are two types of respiration:

It is found in many products Alcoholic Fermentation is used to make bread and alcohol products – using yeast Lactic Acid Fermentation is used to make yogurt and some cheeses - uses bacteria

Stages of Cellular Respiration Steps of: 1. Glycolysis - Process of turning glucose into 2 molecules of pyruvic acid. This is an anaerobic process – no oxygen needed.

Gylcolysis Total of 4 ATP produced Takes 2 ATP to run gylcolysis Net gain?

Step 2: Fermentation Alcoholic Fermentation Pyruvic Acid is broken into : Ethyl alcohol and CO2 Ex. Bacteria and Yeast Lactic Acid Fermentation Pyruvic Acid is broken into: lactic acid Ex. Sour milk, sore muscles

Lab 14:Yeast Respiration Food D: Table Sugar Food C: Milk sugar Food A: fruit sugar

Key point : Electrons release energy when they move They move toward something that attracts them more.

Question 1 What was in the balloon?

Was there energy released? Question 2 Was there energy released? What evidence do you have?

What caused the explosion? Question 3 What caused the explosion? H+ e- O

Energy transfer Depends upon the tendency of substances to attract electrons Which of the substances that were originally in the balloon were more willing to give electrons away?

Other examples of energy transfer Rust Electrons from Iron (with water) are shared with Oxygen to create Lemon Battery Electrons move from zinc (A) Along copper (D)

Both matter and energy are conserved in any reaction Key point 2 Both matter and energy are conserved in any reaction

Role Play: Need for electron donors and acceptors Rules for moving electrons: Each letter can only have one electron at a time Electrons can move only to a nearby carrier. Electrons can move only to a lower energy level.

Role Play: Need for electron donors and acceptors Why did the electrons stop moving? What was released at each step as the electrons moved?

Key point 1 and 2 continued: Energy is released when electrons move. What form will that energy take? What is required to keep electrons moving?

Where will the electrons stop moving? A C E D B B D E A C A B C D B D E A B C E A B C D C E A B E

Which movement will release more energy 1. A to B, A to C 2. B to D, B to E 3. B to D or B to E 4. E to A or A to D

Hydrogen fuel cell Hydrogen is the electron donor

Structure of Mitochondria Found in all eukaryotic cells

Steps in Aerobic Respiration 2. Kreb’s cycle 3. Electron transport chain (Glycolysis takes place) C6H12O6 + O2 + 2 ATP H20 + CO2 + 38 ATP Net Gain of ATP?_________________

Steps in Aerobic Respiration Glycolysis – breaks a 6C structure into 2 3 carbon pyruvic acids Happens in cytoplasm 2 NADH+ are produced

A new player: NAD+ NAD+ is an Electron Acceptor When glucose is broken down H+ is transferred to NAD+ Forms NADH+ is an electron carrier

What do we have?

Aerobic Respiration Step 2: Kreb’s cycle Occurs if Oxygen is present Pyruvic acid enters mitochondria This forms CO2, NADH+, Acetyle-CoA, 2ATP Kreb’s cycle begins Where is the energy from glucose?

Kreb’s Cycle

Aerobic Respiration Step 3: Electron Transport Chain 34 ATP

Players in Electron Trans. Chain ATP Synthase Rotor and central shaft 3 bulbs, where ATP is made Entry and exit port for protons

ATP synthase How many ATP are made with one complete turn of the ATP syn. How many protons did it take?

Players in Electron Trans. Chain Carbon Molecules NAD+ Proton Pumps: complex 1, complex 2, complex 3 Quinone (electron carrier) Cytochrome c (electron carrier – only 1 e at a time) ATP Synthase

Steps in Aerobic Respiration 2. Kreb’s cycle 3. Electron transport chain (Glycolysis takes place) C6H12O6 + O2 + 2 ATP H20 + CO2 + 38 ATP Net Gain of ATP?_________________

Cell Respiration Song

Photosynthesis

Photosynthesis occurs in the chloroplasts.

Structure of a chloroplast Thylakoids – pigment found Light strikes the thylakoids

Chloroplast Structure

Thykaloid Stucture

Stage 1: Light reactions Light energy is absorbed Chlorophyll – absorbs blue and red light, reflects yellow and green. Photo part of photosynthesis

Stage 2: Light to Chemical Use of water – split into H and O2 Oxygen is released as waste. Production of electron carrier and ATP.

Stage 3 Calvin Cycle Sugar Factory, Light independent ATP , NADPH, CO2 needed Production of glucose (carbohydrate) C6H12O6.

How are aerobic respiration and photosynthesis related? C6H12O6 + 02 + 2 ATP CO2 + H20 + 38 ATP CO2 + H20 + light energy O2 + C6H12O6 How is this an important part of the ecosystem?