BIOCHEMISTRY, BIOMEDICINE & PHARMACEUTICS

Multiple Choice Questions on Tricarboxylic Acid or TCA Cycle 1) The conversion of pyruvate to acetyl CoA is catalyzed by the enzyme pyruvate dehydrogenase. In this reaction a) NADPH is oxidized to NADP b) NADH is oxidized to NAD c) NADP is reduced to NADPH d) NAD is reduced to NADH 2) In the tricarboxylic acid cycle, the reaction for the conversion of pyruvate to acetyl CoA is known as a) Oxidative decarboxylation b) Oxidative phosphorylation c) Reductive biosynthesis d) Reductive decarboxylation 3) Which of the following is false regarding the enzyme pyruvate dehydrogenase? a) It is a multi-enzyme complex b) It catalyzes the reversible reaction (conversion of pyruvate to acetyl CoA) c) The pyruvate dehydrogenase complex is a mitochondrial enzyme d) It requires thiamine, flavin, and nicotine vitamin co-enzymes 4) Pyruvate dehydrogenase is an important regulatory enzyme that senses the energy status of the cells. Which of the following is NOT the regulator of pyru...

Multiple Choice Question on T cell Development, Differentiation, and Activation 1) T cells (T lymphocytes) are crucial in the recognition of antigens presented by self-MHC. The T cell progenitors undergo proliferation and differentiation in the thymus and form a mature T cell.  Which of the following organ is the origin of T cell progenitors ? a) Thymus b) Hepatocytes c) Bone marrow d) None of the above 2) What is the characteristic feature of progenitor T cells that have migrated to the thymus? a) They express T cell receptor/CD3 complex b) They express CD28 cell adhesion molecule c) They express CD4 or CD8 co-receptor d) None of the above 3) Which of the following cell adhesion molecule is present in the T cell progenitors required for homing these cells into the thymus? a)CD25 b) CD44 c) IL-2 d) CTLA-4 4) Pre- T cell receptor complex consists of the β chain of TCR & CD3 molecules that are formed during the proliferation of T cells.   Th...

          MCQs on Probiotics and Prebiotics, components of microbiology What is the primary focus of microbiology in the context of probiotics and prebiotics? a. Developing new antibiotics b. Investigating the role of vitamins in digestion c. Studying harmful bacteria in the gut d. Understanding the interactions between microorganisms and the host What are probiotics? a. Nutrients essential for digestion b. Harmful microorganisms in the gut c. Live microorganisms that provide health benefits      d. Non-digestible fibers in the diet Which of the following foods is a good source of probiotics? a. Apples b. Chicken breast c. Whole wheat bread d. Yogurt Prebiotics are best described as: a. Foods that nourish beneficial gut bacteria b. Digestive enzymes c. Harmful bacteria in the gut d. Probiotic supplements What is the primary role of prebiotics in the gut? a. Killing harmful bacteria b. Nourishing beneficial gut bacteria c. Providing energy for the...

                          MCQs on Encephalitis, diagnosis and treatment 1. A 29-year-old male presents to the emergency department with a sudden onset of symptoms. He appears confused and disoriented, with slurred speech and muscle weakness. His family members report that he had a high fever and severe headache for the past few days. They also noticed that he had developed a rash on his chest. The patient has no significant medical history and is generally in good health. He mentions that he had recently returned from a camping trip in a wooded area. Physical examination is done by the healthcare provider, temperature is 101.4°F, blood pressure is 130/80 mm Hg, and oxygen saturation is 98% on room air. The patient appears disoriented and confused, with difficulty answering questions. Neurological examination reveals muscle weakness, particularly in the limbs. Neck stiffness is present. Laboratory tests reveal blood test w...

                            MCQs on Dengue fever, diagnosis and treatment 1. A 45-year-old female residing in Delhi, India presents to the emergency department with a high-grade fever, severe headache, and joint pain. She reports that her symptoms began suddenly a week ago with a fever that reached up to 103°F. She describes headache as intense and located behind her eyes. She complains severe joint pain, especially in her wrists and ankles. She has developed a rash on her arms and legs, which is characterized by small red spots. The patient has no significant past medical history. She has been taking pain reliever medications (ibuprofen) and paracetamol to manage her symptoms. Her family informs that other people in her neighbourhood are also sick with similar symptoms.  Upon examination, her temperature is 103°F, blood pressure is 114/75 mm Hg, respiratory rate is 18 breaths per minute. The patient appear fatig...

                             Lecture notes on CRISPR-Cas9 technology CRISPR-Cas9 technology is a revolutionary gene-editing tool that has had a profound impact on the field of genetics and molecular biology.  The use of CRISPR-Cas9 for genome editing in microorganisms and its potential applications in medicine, agriculture, and biotechnology is an active area of research. In 2020, the Nobel Prize in Chemistry was conferred upon Emmanuelle Charpentier and Jennifer Doudna for their pioneering contributions to the development of CRISPR-Cas9 technology. For more information on CRISPR-Cas9: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9377665/ 1. What is CRISPR-Cas9? CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) and Cas9 (CRISPR-associated protein 9) are components of a bacterial immune system that helps bacteria defend against viral infections. Scientists have adapted this system to edi...

Overview of the Topics Anticoagulant Drugs (Click Here) Thrombolytic Drugs (Click Here) Antiplatelet Drugs (Click Here) Multiple Choice Practice Questions (Click Here) Antiplatelet drugs - Platelet aggregation occurs in response to vascular injury - The aggregation of platelets  in the coronary artery can lead to the development of atherosclerotic plaque - It may precipitate coronary vasospasm, myocardial infarction, and stroke Clinical Indication - Prophylaxis of arterial thrombosis - Therapeutic management of myocardial infarction and stroke - Should be infused within 2 hours of myocardial infarction or stroke for significant benefit Clinically Important Antiplatelet Agents - Thromboxane A2 pathway, ADP pathway & GPIIb/IIIa receptors are the therapeutic targets to prevent platelet activation and aggregation. The drugs include - Aspirin - Clopidogrel - Abciximab Aspirin - Aspirin inhibits platelet aggregation and prolongs bleeding time  - Aspirin irreversib...

Case objective a) Discuss an overview of bilirubin metabolism b) Discuss neonatal physiological jaundice c) Discuss inborn errors of bilirubin metabolism d) Discuss biochemical/molecular diagnosis Case Presentation : A 48-year-old woman had a history of jaundice for decades, with no related symptoms. A laparoscopic evaluation showed a smooth liver with normal consistency and morphologic features but with a grossly black appearance. A biopsy specimen revealed coarse, deep-brown, pigmented granules on periodic acid–Schiff staining primarily at the canalicular pole of the hepatocytes and especially in the pericentral zones.  The laboratory investigation results are given below: Serum Total bilirubin - 4.6 mg/dL Direct-reacting bilirubin - 2.4 mg/dL Aspartate transaminase - 38 U/L Alanine transaminase - 25 U/L Alkaline phosphatase - 45 U/L Serum Albumin- 4.2 gm/dL Prothrombin time- 12 seconds Expression of the multidrug resistance associated protein 2 (MRP2) was ab...

                                      MCQs on Gastrointestinal infections 1. A 24 year old female student traveled to a rural area in a developing country for a research purpose and returned 5 days ago. She comes to the emergency department with a 3-day history of watery diarrhea, abdominal cramps, and occasional episodes of nausea. She reports passing loose stools more than 10 times a day and feeling weak due to fluid loss. The abdominal cramps are localized in the lower abdomen and are exacerbated before bowel movements. The patient denies any bloody stools or fever. Upon examination, she appeared dehydrated, has tachycardia (elevated heart rate). She has low blood pressure, dry mucous membranes. Mild tenderness in the lower abdomen is found with no signs of abdominal distension or rigidity. Microscopic examination of stool samples is conducted, it reveals the presence of trophozoites of a p...

1)The first 2022 monkeypox virus outbreak occurred in Nigeria. What are the common possible routes of transmission of the virus to humans? Select all the correct answers : a) Humans to humans b) Animals to humans c) Humans to animals d) Animals to animals 2) Monkeypox infection has been declared a public health emergency in 2022 by the World health organization due to the worldwide spread of the virus. According to health agencies in the USA which of the following age group are at higher risk? a)Children 5 to 10 years old b)Males 18 years and above      c)Infants  d)Pregnant women 3)Which of the following are the common symptoms related to monkeypox infection? a) High fever, raised skin lesions, swollen lymph nodes        b) High fever, diarrhea, and vomiting c) High fever, flat skin lesions, vomiting d) High fever, seizures, and loss of appetite 4) Smallpox and monkeypox viruses come under the same genus of viruses known as orthopoxvirus. When wa...

Multiple Choice Questions on Major discoveries in Microbiology  1) The Nobel prize winner physician and microbiologist Robert Koch was the first scientist to identify the causative agent for the infectious disease called anthrax in humans. Which other microorganisms were first reported (isolated) and identified by him?  Select all the correct answers: a) Mycobacterium tuberculosis b) Bacillus anthracis   c) Bacillus cereus d) Vibrio cholerae   e) Escherichia Coli 2) The discovery of the antibiotic penicillin in treating infection caused by Staphylococcus spp  is considered a revolutionary contribution in the field of medicine.  Who was the first scientist to discover the antibiotic penicillin ? a) Edward Jenner b) Alexander Fleming c) Paul Ehlrich d) Selman Waksman e) Louis Pasteur 3) Which of the following scientist had a major contribution in the field of science who developed a compound microscope and coined the term ‘cell’? a) Robert Koch b) An...

                                         MCQs on Nipah virus with a clinical case 1. A 41 year old male fruit farmer residing in rural village Kerala, India comes to the local health clinic with a high fever, severe headache, and dizziness that he says started a week ago. He has been experiencing vomiting and muscle pain with difficulty in breathing. Upon examination, the healthcare provider notices the patient has a high fever of 39.5°C (103.1°F), he exhibits signs of confusion and disorientation. His breathing is labored, and has a cough. He has been experiencing vomiting and diarrhea, complains of severe muscle pain and weakness. His wife informs the examiner that there has been an outbreak of an unknown illness in their village, and some of their neighbors have fallen ill as well.  Blood sample is taken for bacterial culture, and to check virus antibodies and antigens. Serol...