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الامام Br *NH2

Ethanol (CH3CH2OH) is the alcohol found in beverages. It is oxidized in the body to acetaldehyde by the enzyme alcohol dehydrogenase. Methanol (CH3OH), also known as wood alcohol, is converted to formaldehyde by the same enzyme. Acetaldehyde is toxic, but formaldehyde is far more toxic to humans, which is why the ingestion of relatively small amounts of methanol can cause blindness or death. One treatment for mild methanol poisoning is the administration of ethanol. Why might a doctor choose this treatment? A. Ethanol likely irreversibly binds to alcohol dehydrogenase which prevents the formation of formaldehyde. B. The doctor has given up on the patient and administers ethanol for sedation. C. Ethanol must act as a competitive inhibitor for the alcohol dehydrogenase and therefore slows the formation of formaldehyde. D. The ethanol is likely an uncompetitive inhibitor and binds to a site other than the active site of the enzyme.

B

For a given acid HA, it was determined that at pH 6.0 the concentration of the conjugate base [A] was 0.075 M and the acid [HA] was 0.025 M. What percent of this acid is ionized at pH 6.0? What is the pKa of this acid? What pH would this acid be 50% lonized?

Q5:

Truo or fals

One pathway for the metabolism of D-glucose 6-phosphate is its enzyme-catalyzed conversion to D-fructose 6-phosphate. Show that this transformation can be accom- plished as two enzyme-catalyzed keto-enol tautomerisms. СНО CH,OH C=0 enzyme catalysis Но Но H OH H H. O- H- -HO- ČH,OPO, ČH,OPO, D-Glucose 6-phosphate D-Fructose 6-phosphate

Complete each of the following chemical reactions.

The role of calcium ions (Ca4) in neural signal transmission is to cause the release of neurotransmitter molecules from sodium-potassium pumps in the presynaptic neuron. repolarize the postsynaptic cell after transmission has been completed. increase the activity of the sodium-potassium pumps in the presynaptic cell cause the release of neurotransmitter molecules from synaptic vesicles in the presynaptic neuron.

Ans

Is CaCl2 (aq) + Na₂CO₃ (aq) → CaCO3 (s) + 2NaCl (aq) reversible or irreversible reaction

Consider a protein with five amino acids and three possible energy levels (separated by 1 J/mol) each amino acid can occupy. At what temperature will there be 45% of molecules in conformation A and 55% of molecules in conformation B? Comment on the size of this number and what distribution you would expect at room temperature. What does this mean about how "different" these energy levels are? Look back at the figure and propose an error made in reporting units. What energy unit would have likely been more appropriate in this case?

PAP Chemistry-2903012-42100P-1/ Le Chatelier's Principle/ Lesson 128 2. Zinc (Zn) granules react slowly with dilute hydrochloric acid (HCI), but much faster if the acid is concentrated. Zn(s) 2HCI(aq)ZnCl2(aq) + H2(g) Zinc + Hydrochloric Acid Zinc Chloride + Hydrogen What causes the reaction to proceed faster with concentrated acid? The concentrated hydrochloric acid causes more hydrogen gas to be produced. The pressure of hydrogen gas molecules increases as concentration increases. The concentrated hydrochloric acid molecules move faster than in dilute acid. There are more collisions between the zinc and concentrated hydrochloric acid. PREVIOU

On the occasion of World Health Day, Dr. Satpal organized a ‘health camp’ for the poor farmers living in a nearby village. After check-up, he was shocked to see that most of the farmers suffered from cancer due to regular exposure to pesticides and many were diabetic. They distributed free medicines to them. Dr. Satpal immediately reported the matter to the National Human Rights Commission (NHRC). On the suggestions of NHRC, the government decided to provide medical care, financial assistance, setting up of superspeciality hospitals for treatment and prevention of the deadly disease in the affected villages all over India. (i) Write the values shown by (a) Dr. Satpal (b) NHRC. (ii) What type of analgesics are chiefly used for the relief of pain of terminal cancer? (iii) Give an example of artificial sweetener that could have been recommended to diabetic patients.

Scenario A: 1 mole of glucose in the presence of unlimited oxygen is metabolized through aerobic respiration. Scenario B: 1 mole of glucose in the absence of oxygen is metabolized through anaerobic respiration. Would the number of moles of carbon dioxide produced in Scenario A be greater than, less than, or equal to the number of moles of carbon dioxide produced in Scenario B? Justify your answer.

A discharge pipe releases small amounts of various alcohols from an industrial fermentation process into a lake. Local scientists would like to estimate the rate at which the alcohols are degrading in the lake. One of them, butanol (C4H9OH), is released to the lake at a rate of 20 kg/day. Butanol is measured in the lake water on several occasions at a concentration of 10-4 kg/m3; no butanol is detected in the inflowing stream. Average streamflow at the outlet of the lake is measured to be 3 x 104 m3/day. What is the magnitude of internal sinks of butanol? Assume there is not butanol exchange with the atmosphere.

Predict the products of the following hypothetical biochemical reaction: lago = + 2 H₂O Specifically, in the space below draw the chemical structure of each product of this reaction. You can assume the reaction is catalyzed by an enzyme and takes place at physiological pH. Note: if there is more than one product, you can draw them in any arrangement you like. But don't draw more than one copy of any product, even if the reaction produces more than one molecule of it. You can use common abbreviations for small molecules, like "H₂O" for water.

Can the molecule on the right-hand side of this organic reaction be made in good yield from no more than two reactants, in one step, by moderately heating the reactants? ? Δ 100 • If your answer is yes, then draw the reactant or reactants in the drawing area below. You can draw the reactants in any arrangement you like. • If your answer is no, check the box under the drawing area instead.

When 2-chloro-2-methylpropane, (CH3)3CCl, reacts with aqueous sodium hydroxide, the process is not a “concerted process”; instead a reactive intermediate, (CH3)3C+, is formed as a result of the first step of the reaction mechanism. Explain why this happens.

1. A daily low dosage of aspirin (acetylsalicylic acid) can lower the risk of heart attack and stroke for individuals at risk. Aspirin suppresses the generation of prostaglandins by irreversible binding to the enzyme COX-1. Inhibition of prostaglandin synthesis lowers the production of thromboxanes that are responsible for the aggregation of platelets and the formation of blood clots. You will explore the mechanism of aspirin binding. 1.1 The average pH of the human body is 7.4 (also known as a physiological pH). Draw the structure of aspirin at a physiological pH. OH 1.2 Aspirin reacts with the amino acid Serine. What is the structure of serine? Draw the structure of the tripeptide Ala-Ser-Trp (draw these structures as they exist at physiological pH) serine Ala-Ser-Trp 1.3 Aspirin reacts with Serine 530 of COX-1 by transesterification reaction. Draw a general mechanism of acid-catalyzed transesterification reaction. Use HA as an acid. 1.4 Draw an arrow-pushing mechanism for the…

Complete the following chemical reactions according to the type it belongs to:

Based on a grade 11 chemistry student, answer the following question based on the provided tables: Part G:  Final Identification of the Poison By this time, Tylenol has been pulled off the shelves at all of the stores in the area and a nationwide recall has been announced.  Several suspicious capsules have been found and tested.   The contents of the capsules contain a compound with a nitrogen content of greater than 15% and a carbon content of less than 50%.   What is the poison in the capsule?  Provide calculations to support your answer.

← + 5 2 QT ΑΙ 1. SECTION A Answer BOTH questions in this section (Each question is worth 20 marks) Answer ALL parts of this question. (a) Compare the structure of the ß-lactam antibiotic A with antibiotic X shown in Figure Q1(a) in terms of how structural differences affect the following properties; (i) Spectrum of activity. (ii) Resistance to ẞ-Lactamases. (iii) Oral bioavailability. (3 marks) (3 marks) (3 marks) (b) HH H H ΗΝ Ξ S ΗΝ Ξ S CO₂H A CO₂H X Figure Q1(a) The drugs that are available for Highly Active Antiretroviral Therapy (HAART) can be broken down into five classes. Define three of these classes providing one drug example for each. (6 marks) Question 1 continued on page 2....

Part 3 of 3 Modify the structure of lactulose to show the monosaccharide products that form from hydrolysis. You may draw the structures in any arrangement that you like, so long as they aren't touching. он H сн, он :☐ Он × 5 H H HO снон Сн, он H Он Н д- Н Н OH Н

CH3NH₂ H₂O

When Fructose (shown below) undergoes reduction in the presence of H2 and Pd, two compounds are generated. What is the relationship between the two compounds generated? ОН Но— Н H. OH H OH HO.

Which of the following factors primarily dictates the distribution of terrestrial biomes on Earth? The history of human development and civilization ㅎㅎㅎ The population density of animals Climate variables like temperature and precipitation The prevalence of certain rock and soil types

Classify the following biomolecules given below NH2 но OH HO-ÇH2 H H H ОН H H СНО CH3(CH2)22 `O(CH2)1¬CH3 H -Ç-OH НО-с—Н H-C-OH H-C-0H H H H || CH2OH H3N -C- N -C - CH,OH H

Please send me the question in 20 minutes it's very urgent plz

H CH3 H₂C-N-CH₂-C-CH₂- CH3 OH The reason that this compound is required in the diet of humans is that it: O is part of the coenzyme A molecule. O helps fatty acids cross the inner mitochondrial membrane. O is involved in the reoxidation of cytosolic NADH under anaerobic conditions. O is a precursor of one of the most important oxidizing agents in cells. O is part of the flavin adenine dinucleotide molecule. EES

Illustrate the INTERMOLECULAR bonding of CH4 with itself

The compound provided belongs to what class of biological compounds? H3N CH C—0 N CH₂ NH A/