Biochemistry

Short Essay Questions

Q1: A 16 year old female presents in emergency with severe hypoglycemia and hepatomegaly. On lab investigation she is found to have lactic acidosis and hyperuricemia. On histological examination, her cells show increased deposition of glycogen.

a) Which enzyme is deficient in this patient? 1.5

b) Explain the cause of lactic acidosis and hyperuricemia in this patient. 3.5

Q.2

a)which step in Cholesterol Synthesis is the rate limiting step? 2.5

b) Give a summry of enrgy yield from the oxidation of Palmitoyl CoA? 2.5

Q.3

a) Define Transamination.

b)

i) Name two important enzymes involved in Transamination reactions.

ii)What is their diagnosis value in liver disease and non-hepatic disease ?

Q.4

Draw and label Electron Transport Chain along with complexes , sites of proton pump and site specific inhibitors.

b) How hyperuricemia occours in Lesh-Nyhan Syndrome?

Q.5

a)

i) Give characteristic of primer used in replication process.

ii) Write two applications of PCR

b)

i) What is reverse transcription?

Which enzyme is required for reverse transcription?

Q.6

a) A 45 yaar old obese female presents in emergency department with history of pain in right side of chest along with nausea and vomiting for two days. She also gives history of clay colored stools. On examination , she appears jaundiced. her serum Cholesterolis 300 mg/dl(normal upto 200mg/dl). What is the most probable cause of pain in right side of her chest. Name primary and secondary bile salts.

B) List the enzymes required for protein digestion. How pepsinogen is converted into pepsin?

Q.7

a) A 40 year old laborer fainted on a hot summer evening and was brought to hospital. His skin was cold and clammy and blood presure was 100/60mmHg

i) Write his normal distribution of fluid in ECF and ICF compartments?

ii) Name one buffer each of ICF and Kidney.

b) What is gluconeogensis? Enumerate the major precursors of Gluconeogenesis.

Q.8

a) a 25 Year old female who has never menstruated came to infertility clinic. Ultrasound report shows bilateral atrophy of ovaries. Lab report shows increased testosterone level. What is above type of ammenorhea called ? If hypothalmus and pititry are normal, how will you diagnose the case biochemically?

b) Explain the functions of Insulin on carbohydrates and lipid metabolism.

Q.9

a) What is the rate limiting enzyme of Urea Cycle ? Why ammonia Intoxication is life threatening?

b) Describe the reaction catalyzed by acetyl CoA carboxylase. How is activity is regulated to control the rate of Fatty Acid Synthesis?