Enzyme classification
Enzyme classification Read More »
Biosynthesis of cholesterol The biosynthesis of cholesterol may be divided into five steps: (1) Synthesis of Mevalonate from acetyl-CoA. (2) Formation of Isoprenoid units from Mevalonate by loss of CO2. (3) Condensation of six isoprenoid units forms Squalene. (4) The cyclization of Squalene gives rise to the parent steroid, Lanosterol. (5)Formation of cholesterol from lanosterol.
Biosynthesis of cholesterol- a quick revision Read More »
Case Details A 40-year-old man presents with chest pain that radiates to his left jaw and shoulder. He is diagnosed with a myocardial infarct (heart attack) and is prescribed statin medication. Statins are competitive inhibitors of HMG CoA reductase, which converts HMG Co A to which of the following? Isopentenyl pyrophosphate Mevalonate Geranyl pyrophosphate Farnesyl
The reaction catalyzed by HMG Co-A Reductase Read More »
Steps of de novo synthesis of cholesterol Cholesterol is derived from diet, de novo synthesis, and the hydrolysis of cholesteryl esters. A little more than half the cholesterol in the body arises by synthesis (about 700 mg/d), and the average diet provides the remainder. The liver and intestine account for approximately 10% each of the
Steps of de novo synthesis of cholesterol Read More »
Structure and functions of cholesterol Cholesterol is the major sterol in the animal tissues. The structure of cholesterol consists of four fused rings (the rings in steroids are denoted by the letters A, B, C, and D), with the carbons numbered in the sequence, and an eight numbered, and branched hydrocarbon chain attached to the
Structure and functions of cholesterol Read More »
Case details The peripheral blood film (figure) of a strict vegetarian suffering from generalized weakness, easy fatigue, sore tongue, and foot drop has been displayed. What might be the diagnosis? Case details Most probably, the patient is suffering from megaloblastic anemia due to cobalamine deficiency. The cause for this anemia is a strict vegetarian dietary
A 23 –year- old female was brought for consultation by her mother, who was troubled by her daughter’s continuous fatigue, dizziness, and loss of weight. The patient was 6 feet 2 inches tall and weighed 100 pounds. Further questioning revealed that the young woman had been virtually fasting for four months, hoping to obtain a
Starvation induced metabolic alterations Read More »
Case details A 54- year-old man with Type 1 diabetes is referred to an ophthalmologist for evaluation of developing cataracts. Blood chemistry results are shown below: Fasting blood glucose 198 mg/dl Hemoglobin A 15 gm/dl Hemoglobin A1c 10% of total Hb Urine ketones Positive Urine glucose Positive Which of the following enzymes is most strongly
Question of the week Read More »
1-State Chargaff’s rule In DNA molecules, the concentration of deoxyadenosine (A) nucleotides equals that of thymidine (T) nucleotides (A = T), while the concentration of deoxyguanosine (G) nucleotides equals that of deoxycytidine (C) nucleotides (G = C). 2- What is meant by hyperchromicity of denaturation? The conjugated double bonds of purine and pyrimidine derivatives absorb
Molecular Biology- Viva Questions- Set -1 Read More »