Question

Purpose

        The clear understanding of energy transformations (Cellular Respiration) by cells explains how cells can release energy from nutrient molecules like carbohydrates and others. Completing this assignment will assist you in developing clarity of how cells function energetically on the planet. These principles of Cellular Respiration will help clarify the Course Content Learning Outcomes numbered 2 (Understand the basic principles and ideas of chemistry and organic chemistry) and 4 (Able to explain the concept of a cell and describe the functions of its parts) for this course. You will also understand the Campus Wide Outcome of Critical Thinking (See page 3 (Critical Thinking) of the syllabus).

Task

        Armed with a textbook (Chapter 7), the Cellular Respiration Power Point presentation, or other reliable sources answer the following questions about Cellular Respiration. Be creative in how you approach and answer each question. Read the source and then write your answer in your own words so that it becomes your answer. Remember in science there are no “correct” answers but rather explanations of phenomena. This assignment will be due??? (Exact date will be given in class).

Criteria

       The possible points for each question are in parenthesis after the question number. A complete answer to each question will involve being cognizant of the principles of the processes of Cellular Respiration and explaining how the process relate to energy release and how they relate to each other in terms of energy release. Clear answers will have cellular parts labeled clearly with descriptions and definitions that are clear, concise, and will contain enough detail that anyone reading your answer could potentially draw the same conclusions that you have by answering the questions.

1. (6) In your own words, describe the overall goal of aerobic cellular respiration and identify the specific cellular sites of each of the four processes (Glycolysis, Transport Step (the steps between glycolysis and the Kreb’s cycle), Krebs cycle, and the ETC) which occur during cellular respiration.
2. (8) Describe the steps of the three major events of Glycolysis: Investment, Splitting, and Harvest to include how each of these adds to the efficiency of the breakdown of glucose to pyruvic acid and producing ATP.
3. (6) Describe the steps of the Transport Step of pyruvic acid between glycolysis and the Krebs cycle Enzymes.
4. (8) Describe the steps of the two major divisions of the Krebs cycle: Destroying and Re-arranging to include in your answer how each of these adds to the efficiency of the breakdown of acetic acid and producing ATP.
5. (8) Describe the Electron Transport Chain, system, or shuttle (ETC) in five steps or less and showing the major players which run this system to produce ATP.
6. (4) Describe Figure 7.11 in the textbook or why is having a complete balanced diet as it applies to your eating habits, attempts to lose or gain weight, or maintaining a healthy life style.

Answer 1

ANS (2)-Glycolysis---> It is the metabolic pathway required by our body in order to produce the energy in the form of ATP (adenosine triphosphate )and NADPH(nicotinamide adenine dinucleotide phosphate ) by breaking down the 1 glucose molecule into 2 pyruvate molecules.

• The glycolysis pathway is the first stage of cellular respiration and it does not require the presence of oxygen that why it is a highly- independent oxygen pathway. that occurs in the cytosol of a cell.
• These ATP and NADPH is entered into the Kreb cycle in order to produce more energy.

INVESTMENT PHASE

• It is the first phase of glycolysis pathway where 2 molecule of ATP is added to the 1 molecule of glucose molecule to convert it into glucose-6-phosphate molecule where phosphate molecule from ATP is released and added to the 6 carbon position of the glucose and ATP converts into ADP. so basically its the investment of ATP in a metabolic pathway.
• These 2 ATP molecules are required to power up the glycolysis pathway.

SPLITTING PHASE

• In this the second phase of glycolysis pathway where 6 carbon molecule named as  fructose-1- phosphate is split into 3 carbon molecules named glyceraldehyde 3 phosphate and dihydroxyacetone phosphate in the presence of an enzyme called aldolase.
• The dihydroxyacetone molecule and glyceraldehyde 3 phosphate are interchangeable molecules, so dihydroxyacetone is converted into glyceraldehyde 3 phosphate. in the presence of enzyme triose phosphate isomerase. This conversion occurs because glyceraldehyde 3 phosphate is on the direct pathway of glycolysis metabolism instead of dihydroxyacetone.

HARVESTING PHASE

• This is the last phase of the glycolysis pathway which includes the production of energy in the form of 2 ATP and 2 NADPH molecules.
• Apart from it the production 2 molecules of water and 2 molecules of pyruvate sugar also occurs in this phase.

Overall end products glycolysis pathway

Glucose + 2 ATP + 2NAD + 2P -------------------->2 Pyruvate +2 NADH + 2 ATP

• 2 ATP molecules
• 2NADPH molecules
• 2 pyruvate sugar molecule.

** In whole glycolysis pathway 4 ATP molecules are generated but only 2 ATP is considered as the net product of glycolysis because 2 ATP molecules were already used in the investment phase of the pathway to power up the pathway.