Question

ons 1. Answer the following questions in a few paragraphs. . What is the basic purpose of cellular respiration? What are the reactants and products of cellular respiration overall? Also, give a basic description of the three main stages of cellular respiration (glycolysis, Kreb cycle, and the electron transport chain) • Your next paragraph will focus on your assigned inhibitor. You should find one to two reliable sources that discuss how your assigned inhibitor works. Focus on the enzyme inhibited by your assigned inhibitor, and the part of cellular respiration that would be affected. - What effect would the presence of your assigned inhibitor have on ATP production? What effect would the presence of your inhibitor have on the amount of NAD+, NADH, pyruvate, and oxygen present in the cell? - If cellular respiration is blocked, can cells switch to a backup method for making ATP?

Answer 1

1. Cellular respiration is the process by which the energy that we get from food that is the biochemical energy is converted to ATP. This is the process which supplies energy to the cell. Cellular respiration happens in the presence of oxygen that is oxygen is combined with food and energy is produced and the waste products,c and water is removed.

The reaction can be summarised as below

Glucose+ 6Oxygen$\rightarrow$ ATP+ 6CO2+6 H20

2. A, Glycolysis is a metabolic process that converts glucose in to pyruvic acid.Glycolysis take place in the cytoplasm of the cell and enzymes needed for glycolysis are present in the cytoplasm. There are 10 step in glycolysis process. The total visible ATP produced in glycolysis is 2. Glycolysis form the basis for both aerobic and anaerobic respiration. After Glycolysis the cells which are having oxygen and are able to utilize it will move on to kreb cycle and others will move on to anaerobic respiration.

The overall process of glycolysis can be written as

Glucose+ 2 NAD + 2 ADP+ 2 Pi$\rightarrow$ 2pyruvic acid+ 2ATP+ 2NADH+2H

B,Krebs cycle (citric acid cycle) occurs in the matrix of mitochondria and 8 catalysed reactions take place in citric acid cycle. The pyruvic acid formed from glycolysis is converted to pyruvate and pyruvate is converted to acetyl co- A. This acetyl co_A is the starting reactant in kreb cycle. Since 2 pyruvic acid molecule are formed from glycolysis 2 acetyl co-A will enter in to Krebs cycle. The significance of kreb cycle is that it donate protons and electrons for the electron transport chain as NADH and FADH2. Another significance of citric acid cycle is that the several intermediate products of this cycle enter in to various biochemical pathways. The overall reaction in Krebs cycle is

2 acetyl co-A+ 6NAD+ 2FAD+2ADP+2Pi$\rightarrow$ 4 CO2+ 6NADH+2FADH2+2ATP+6H

C, In electron transport chain oxidative phosphorylation of NADH and FADH2 produced in the citric acid cycle is happening and ATP is produced. It happens in the inner membrane of mitochondria. In this electron transport chain a series of electron transferring is happening and the final acceptor of electron in it is Oxygen. As a result of this redox reaction the concentration of hydrogen ions in the mitochondrial matrix increases and it diffuse out of the matrix and in this process it activates ATP synthase leading to the production of ATP. There are four complexes in electron transport chain. In electron transport chain three ATPs are produced from NADH and 2 ATP from FADH2

3,4. The inhibitor that is been designed is named as pk123. This drug has an inhibitory action in glycolysis. Thus the later stages of cellular respiration is also blocked. pk123 specifically inhibit pyruvate kinase an enzyme involved in the last stage of Glycolysis. Pyruvate kinase catalyse the conversion of phosphoenolpyruvate to pyruvate and a molecule of ATP is produced. Thus the drug p123 block the production of this ATP and pyruvic acid. Since pyruvic acid is not produced later stage of cellular respiration will be effected. This drug can be used for the treatment of cancer. Cancer cells entirely depends on Glycolysis for energy production. So blocking of pyruvate kinase will be an innovative therapy for cancer treatment.