Cellular Respiration Assignment Free Essay Example

– Cellular Respiration Assignment – 1. What two molecules are formed when a phosphate is removed from ATP? There are three phosphate groups in ATP molecule (Adenosine Triphosphate), when removing one phosphate molecule, ADP molecule is formed (Adenosine Diphosphate). 2. What is the function of ATP? Describe the molecule. The function of ATP is storing energy within a cell. ATP is adenosine triphosphate, C10H16N5O13P3, a high energy complex, giving the necessary power to push metabolistic reactions in the body. Its composed of adenosine, a ribose sugar, and three phosphates.

. Describe how ADP is converted into ATP. By adding one phosphate molecule to ADP, it becomes ATP. 4. Differentiate between oxidation and reduction reactions. Oxidation is a process, in which the atom or ion is increasing its oxidation sate. This will result in loss of electrons. The species that are being oxidized, are the reduction agents. Reduction is a process, by which the atom or ion is decreasing its oxidation state. This will result in a gain of electrons.

Here, the species that are being reduced are the oxidizing agents. . Why is an electron transport system important to living organisms? Because it releases energy from fuel in a slow and controlled fashion. 6. Why are oxidation reactions often associated with the production of ATP? They release energy, thus helping with the production of ATP. 7. In the reaction ADP + P forms ATP is energy stored or released? Stored , because with the addition of a Phosphate molecule ATP is formed. 8. The primary source of energy for the cell is (a) starch (b) cellulose (c) glucose (d) ATP (e) sunlight © Glucose 9.

Why must glycolysis occur before the steps of aerobic respiration can begin? Glycolysis breaks glucose into two pyruvate molecules, to be broken down in the citric-acid cycle. For this reason, it must occur before the steps of aerobic respiration can begin. 10. What is the purpose of the phosphorylation of glucose in glycolysis? If the cell needs energy or carbon skeletons for synthesis, then glucose 6-phosphate is targeted for glycolysis. Glucose 6-phosphate is first isomerized to fructose 6-phosphate by phosphoglucose isomerase.

This reaction converts glucose 6-phosphate to fructose 6-phosphate in preparation for phosphorylation to Fructose-1,6-bisphosphate. The addition of the 2nd phosphoryl group to produce Fructose-1,6-bisphosphate is an irreversible step, and so is used to irreversibly target the glucose 6-phosphate breakdown to provide energy for ATP production via glycolysis. 11. As glucose is broken down into pyruvate, the hydrogen atoms and their electrons are picked up by (a) NAD (b) NAD+ (c) NADP+ (d) NADP (B) NAD+ 12. Explain how the Krebs cycle contributes to the production of ATP.

Makes NADH for ETC, and also produces ATP from oxidation 13. Explain how energy is released in useful packets through the ETC. Energy is released at each cytochrome and, some transport an H+ across the membrane 14. What molecule carries the hydrogen and electrons removed from glucose? NADH 15. What are the waste products of cellular respiration? CO2 & H2O 16. Where in the cell does the ETC occur? Matrix of Mitochondria 17. Describe the role of NADH in cells. The role of NADH is to carry electrons from glycolysis to the Krebs cycle during cellular respiration. 18.

Identify the use of each of the reactants in cellular respiration and the source of each the products. O2 – terminal e acceptor; glucose – source of e; CO2 – produced by Kreb’s; H2O – produced when O2 accepts e – Photosynthesis Assignment – 1. What is the meaning of the word photosynthesis? Photosynthesis is derived from the Greek word photo, meaning “light,” and synthesis, from the Greek work syntithenai, which means “to put together” 2. What are the end products photosynthesis? Oxygen 3. Which organisms are responsible for carrying out the most photosynthesis on the earth?

Blue Green Algae 4. The energy conversion in photosynthesis occurs in three stages. What are they? Photosynthesis occurs in two stages. In the first stage, light-dependent reactions or light reactions capture light energy and utilize it to make energy-storage molecules ATP and NADPH. During the second stage, the light-independent reactions use ATP and NADPH to capture and reduce CO2. 5. State the four factors that must be present to begin the process of photosynthesis. Chloroplasts, H2O, sunlight, CO2. 6. Summarize the events of the light reactions.

Light Reactions of Photosynthesis: Electrons flow to NADP Split Water Pump Protons ATP Production 7. What are the products of the light reactions? NADPH, O2 and ATP 8. In what part of the chloroplast do the light reactions take place? Thylakoid membranes of the chloroplasts. 9. Where in the chloroplast is chlorophyll located? Chlorophyll molecules are embedded in the thylakoid membranes. l0. What is the term for the stacks of disks seen in plants? Grana for plural / Granum for singular. 11. What is the term for the fluid surrounding these stacks?

Stoma, is the fluid matrix that surrounds the thylakoids. I2. What function is served by chlorophyll? Chlorophyll is a molecule that absorbs light and synthesizes it into the energy, in turn giving plants life. Chlorophyll is primarily responsible for the photosynthesis process and hence performs as the basic building block of all life. It also gives plants the green color. 13. What molecule carries hydrogen and electrons during photosynthesis? NADPH – Only NADP carries hydrogen in Photosynthesis. It is reduced by hydrogen to make NADPH(2).

FAD is not a hydrogen carrier in photosynthesis – its a hydrogen carrier in respiration. Electrons pass along a chain of electron carriers during the light dependant stage of Photosynthesis. They lose energy in the process, which is used to photophosphorylate ADP into ATP. The electrons are thereafter combined with the hydrogens which combine with NADP forming the overall compound NADPH(2) 14. Where in the chloroplast does the ETC occur? ETC takes place in the Cristae of the Mitochondria. 15. Where does the Calvin cycle occur?

The Calvin Cycle, also known as the dark reaction, occurs in the stroma. 16. What is the function of the Calvin cycle? Synthesize simple sugars from carbon dioxide. 17. State the products of the Calvin cycle. The immediate products of one turn of the Calvin cycle are 2 glyceraldehyde-3-phosphate (G3P) molecules, 3 ADP, and 2 NADP+ (ADP and NADP+ are regenerated in the Light-dependent reactions). 18. Carbon fixation changes _CO2_ into _Organic Molecules_. 19. What is the source of the oxygen released during photosynthesis?

H2O – Oxygen is produced by photolysis of water. 20. Where does the carbon for making glucose come from? The carbon in glucose, comes from carbon dioxide that enters through the plant through small holes on the bottom, called the stomata. After Calvin Cycle, it becomes glucose and other sugars. 21. What is the purpose of the electron transport chain in photosynthesis? Electron transport chains are the cellular mechanisms used for extracting energy from sunlight in photosynthesis and also from redox reactions, such as the oxidation of sugars (respiration). 2. How do the electrons accepted by the ETC become high energy? Krebs Cycle 23. Where in the cell does the ETC occur’? Matrix of Mitochondria 26. What happens to the ATP produced in chloroplasts? The dark reaction takes place in the stroma within the chloroplast, and converts CO2 to sugar. The dark reaction involves a cycle called the Calvin cycle in which CO2 and energy from ATP are used to form sugar. 28. When plants photosynthesize, they always make more glucose than they require for food. Explain.

Food storage is common in plants to support the life of the plant during periods of low light intensity, to provide readily metabolized energy for high energy demand activities such as flowering and seed production and to over-winter for perennial plants. Not only that, it also needs it to repair or replace tissues when damaged by herbivores or parasites. 29. How are the general formulas for photosynthesis and cellular respiration related? Photosynthesis is the reverse of cellular respiration and vice-versa.

So one forms glucose, while the other breaks it down. The equation for the oxidation of glucose is: C6H12O6 + 6O2 > 6CO2 + 6H2O + Energy released (2830 kJ mol? 1) 6 CO2 + 12 H2O + light > C6H12O6 + 6 O2 + 6 H2O They work like a cycle, with each depending on the other. 30. What is the immediate energy source for the Calvin cycle? ATP (Adenosine Triphosphate) is the main fuel for the Calvin Cycle, with NADPH being the other source for the cycle. 31. What final product in carbon fixation is used to make glucose? G3P