Question

Tele No The first law of thermodynamics states that energy cannot be created or destroyed. If this is the case, why is it said that "energy does not cycle"? 1. 2. In the body, glucose can be broken down via cellular respiration to provide energy, or it can be built into chains of glycogen (or starch for plants) and stored. What determines which reaction glucose undergoes? 3. In the following metabolic pathway, we normally get the final product "G." A-F are reactants; B-G are products, and Bl-E6 are enzymes. We want to harvest the product labeled "D." Briefly, describe a method for how we could accomplish this and why it would work E2 ЕЗ EA E5 E6 El 4. A) State what an enzyme is. B) State what metabolism is and how enzymes are involved in metabolism. C) Briefly describe how enzymes work. D) Describe two situations that would cause enzymes to stop working. Chapter 7 5. What are the GENERAL similarities and differences between photosynthesis and cellular respiration? Please include the following in your answer: A) What types of organisms & /or organelles are associated with each? B) The chemical equation (e.g. What are the inputs and outputs for photosynthesis and cellular respiration?) 6. What is meant by the "light reactions' and "dark reactions" of photosynthesis? A) Please describe these (HINT: inputs, outputs, location in the chloroplast) and B) tell me why they are important and how do they benefit me (relate 3 examples...think "global climate change/Greenhouse Effect" for one)?? Chapter 8 7. Describe "substrate level phosphorylation" and provide 2 examples (Hint: glycolysis) of these important cellular respiration reactions. (You may want to use a labeled drawing to help explain). 8. List the four phases of complete glucose breakdown and where they occur in the eukaryotic cell. Please include your answer which ones release CO:, produce H:O, and the ATP inputs/outputs. in 9. If the breakdown of one 18-carbon fatty acid chain produces 9 acetyl CoA molecules, how many ATP are produced from this single fatty acid chain if all the molecules complete the citric acid cycle and electron transport chain? 10. A) Describe the process of "fermentation/anaerobic cellular respiration" (list the inputs and outputs). B) State why organisms would use this method. C) State the waste products of fermentation in yeast and in animals.

Answer 1

Answer

1) Energy does not cycle the way nutrients and atoms do. Energy enters the ecosystem from the Sun and exits after the organisms have taken as much as they need. Organisms release energy back into the biosphere as heat. Energy also enters the ecosystem from the interior of the Earth. It is usually in the form of heat, not the electromagnetic radiation from the Sun. There are finite amounts of carbon (C), nitrogen (N), and oxygen (O) on the planet. Those elements are recycled through the planet's resources. Energy is different in that it comes into the biosphere and then leaves.

Hence the energy from the sun is not recycled as some energy is absorbed and some is converted into the heat.

2) Both the reactions occurs simultaneously in the body but depending on the need and availability of Glucose. If body requires energy then glucose breakdown predominates over the formation of Glycogen. And if morr glucose is available than for energy requirement then thess excess glucose gets converted into Glycogen.

3) to harvest D, we have to inhibit enzyme E4. As a result Conversion of D to E will not occur.

4) A) Enzymes are bio catalysts which increases the rate of reaction without getting involved in the reaction.

B) Metabolism are the set of chemical reactions occurring inside the body.

Enzymes increases the rate of these metabolic reactions by decreasing the activation energy.

C) Enzymes work by decreasing the activation energy of the substrate and by increasing the collision of the substrates also they provide surface area for reactants to collide.

D) presence of an ihibitor that will bind to active site will stop the working of enzyme

Also some conformational changes in the enzyme will stop the working of enzyme