Biology Unit 3 ReviewEnergy

Access Prior Knowledge

• Unit 3 Exam covers all of human knowledge up thru the lessons on Energy

Access Prior Knowledge

• Enzymes– Control biochemical

reactions– Enzymatic activity affected

by …

• Temperature• O C; water freezes• 20 C; room temp• 37 C; body temp• 100 C; water boils• 28 C = 82 F (it’s dyslectic!)

• Graphing & Analyzing Data

• Biochemical Reactions– Hydrolysis– Dehydration Synthesis

• Experimental Control• Bromothymol Blue

– CO2 turns solution acidic

Unit 3 Vocabulary

• Know the words

• Know what the words mean

Photosynthesis (3.1 & 3.2)(To Make with Light)

Carbon+Water -----> Glucose+OxygenCarbon+Water -----> Glucose+OxygenDioxideDioxide lightlight

6CO6CO22 + 6H + 6H22O -----> CO -----> C66HH12120066+6O+6O2 2

lightlight

Photosynthesis is the process by Photosynthesis is the process by which plants and some single-which plants and some single-celled organisms (celled organisms (autotrophsautotrophs) use ) use the energy from sunlight to the energy from sunlight to produce sugar. It is the produce sugar. It is the conversion of light energy into conversion of light energy into chemical energy and is associated chemical energy and is associated with the actions of the green with the actions of the green pigment chlorophyll.pigment chlorophyll.

Two part process:Two part process:light reaction & dark light reaction & dark

reactionreaction

Photosynthesis

• Light Reaction– Light energy (photons) absorbed by

chlorophyll causes release of high energy electrons (e-). Two molecules of water are split into 4H+ and O2.

– High energy e- are passed thru Electron Transport Chain where the energy is used to re-phosphorylate ATP.

– Molecular oxygen (O2) is released.

ADP+Pi ATPADP+Pi ATP

EnergyEnergy

Photosynthesis

• Dark Reaction– ATP energy created in light reaction used

to synthesize glucose from carbon dioxide

– 6CO2 -----> C6H12O6

ATPATP ADP+PiADP+Pi

EnergyEnergy

Photosynthesis

Refer to the diagram on the Refer to the diagram on the left for questions 1 - 4.left for questions 1 - 4.

1.1. What gas is found in the What gas is found in the bubbles? Explain?bubbles? Explain?

2.2. What part of the cell does What part of the cell does the release of this material the release of this material occur in?occur in?

3.3. What happens if the same What happens if the same setup is left in the dark?setup is left in the dark?

4.4. How would you design a How would you design a control for this setup?control for this setup?

Energy in Organic Molecules (3.3)

This is a molecule of glucose. Glucose is a This is a molecule of glucose. Glucose is a molecule that can be easily metabolized to molecule that can be easily metabolized to release energy. Where is the energy stored in release energy. Where is the energy stored in this molecule? this molecule?

Cellular Respiration

• The process by which food is broken down to release energy.

• Which kinds of cells carry out cellular respiration?

• Where does it occur within the cell?

• What is the ultimate goal of cellular respiration?

Glucose + Oxygen -----> Carbon Dioxide + Water+ EnergyGlucose + Oxygen -----> Carbon Dioxide + Water+ Energy

CC66HH1212006 6 + 6O+ 6O22 -----> 6CO -----> 6CO22 + 6H + 6H22O + ATP O + ATP

Cellular Respiration

• Three Stages– Glycolysis– Kreb’s Cycle– Electron Transport Chain

Cellular Respiration

Cellular RespirationGlycolysis

•Glycolysis• Glycolysis occurs in

cytoplasm of the cell• Literally means

“splitting of sugar”• splitting glucose (6C)

into 2 pyruvate (3C)

• produces net gain of 2 ATP and 2 NADH

• occurs with or without oxygen.

Cellular Respiration

Cellular RespirationKreb’s Cycle

• Kreb’s Cycle– Pyruvate moves from the cytoplasm into

the mitochondrion– Pyruvate broken down to carbon dioxide

and water– Process releases hi-E electrons to ETC

along with NADH and FADH2 (H+)– Produces 2 ATPs– Requires oxygen, meaning it is aerobic.

Cellular RespirationKreb’s Cycle

Kreb’sCycleor

pyruvate

Cellular Respiration

Cellular RespirationElectron Transport Chain

• Electron Transport Chain (ETC)– Most energy stored in

original glucose molecule will be released by the electron transport chain

– network of electron-carrying proteins

– located in the inner membrane of the mitochondrion

- Energy released used Energy released used to re-phosphorylate to re-phosphorylate ATPATP

- Hydrogen ions combine Hydrogen ions combine with oxygen to form with oxygen to form waterwater

- HH++ + O + O22 -----> H -----> H22OO

Anaerobic Respiration (3.7)Fermentation

• Lactic Acid Fermentation

– C6H12O6 2ATP + 2 Lactate

(lactic acid)

• Alcoholic Fermentation– C6H12O6 2ATP + 2CO2 +

2 Ethanol

In fermentation, glycolysis proceeds normally, as in aerobic conditions, producing a net gain of 2 ATP. However, without oxygen the pyruvates from glycolysis are broken down into either ethanol and CO2 or lactic acid allowing NADH to be recycled so that fermentation can continue in the cytoplasm and a limited amount of ATP can be produced in the absence of oxygen.

Anaerobic RespirationFermentation

Glucose solution and yeast are placed in the tube shown on the right at 20°C. The tube is sealed. After several hours gas is formed in the collection tube.

1. What process has occurred to produce this gas?

2. What gas is produced?

3. Predict what would happen to the volume of the gas produced if the experiment was conducted at 35°C. Explain.

4. What other material is present in the test tube beside CO2, glucose, yeast, and water?

5. Why do some organisms 5. Why do some organisms only undergo fermentation only undergo fermentation instead of cellular instead of cellular respiration?respiration?

6. Which produces more 6. Which produces more energy: cellular respiration energy: cellular respiration or fermentation? or fermentation?

Cellular RespirationATP and ADP

ATPATP ADP+PiADP+Pi

EnergyEnergyforforCellularCellularFunctionFunction

EnergyEnergyfromfromCellularCellularRespirationRespiration

EnergyEnergy

EnergyEnergy