00
Correct
00
Incorrect
00 : 00 : 00
Session Time
00 : 00
Average Question Time ( Secs)
Retry this test Dashboard

  • Question 1 - Which of the following substances is involved in the respiratory burst by the...

    Correct

    • Which of the following substances is involved in the respiratory burst by the neutrophil?

      Your Answer: NADPh oxidase

      Explanation:

      The respiratory burst is a rapid release of reactive oxygen species (ROS) from neutrophils and other phagocytes. This process is crucial for the destruction of pathogens. The key components and enzymes involved in the respiratory burst include:

      1. NADPH oxidase: This enzyme complex plays a central role in the respiratory burst by converting oxygen (O2) into superoxide anion (O2•-), a reactive oxygen species. This is the initial step in the production of various ROS.
      2. Superoxide dismutase (SOD): This enzyme converts superoxide anion (O2•-) into hydrogen peroxide (H2O2). While SOD is involved in the pathway, the respiratory burst is initiated by NADPH oxidase.
      3. Myeloperoxidase (MPO): This enzyme uses hydrogen peroxide (H2O2) to produce hypochlorous acid (HOCl) from chloride ions (Cl-), which is a potent antimicrobial agent. Myeloperoxidase also produces other reactive species using halide ions.
      4. Catalase: This enzyme degrades hydrogen peroxide (H2O2) into water (H2O) and oxygen (O2). While catalase helps to protect the cell from oxidative damage by breaking down H2O2, it is not involved in the generation of ROS during the respiratory burst.
      5. Adenylate cyclase: This enzyme is involved in the production of cyclic AMP (cAMP) from ATP and is not directly related to the respiratory burst.

    • This question is part of the following fields:

      • Immunology
      • Medicine
      3.4
      Seconds

  • Question 2 - Which of the following makes up the thick filaments in muscle fibers? ...

    Correct

    • Which of the following makes up the thick filaments in muscle fibers?

      Your Answer: Myosin

      Explanation:

      The thick filaments are made up of myosin and the thin filaments are made up of actin. The thick filaments are twice the size of the thin filaments and are aligned to form the A band. The thin filaments extending out from the A band form the less dense I bands.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      1.7
      Seconds

  • Question 3 - Which part of the ECG represents ventricular repolarisation? ...

    Correct

    • Which part of the ECG represents ventricular repolarisation?

      Your Answer: T wave

      Explanation:

      Ventricular repolarisation is denoted by the T wave.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      2.5
      Seconds

  • Question 4 - The tectum as part of the Midbrain contains which structure important in visual...

    Correct

    • The tectum as part of the Midbrain contains which structure important in visual reflexes.

      Your Answer: Superior colliculus

      Explanation:

      The tectum is a part of the midbrain, specifically, the dorsal part of the midbrain. The tectum consists of the superior and inferior colliculi. The superior colliculus is involved in preliminary visual processing and control of eye movement.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      3.1
      Seconds

  • Question 5 - Which neurotransmitter is made from hydroxylation and decarboxylation of tryptophan? ...

    Correct

    • Which neurotransmitter is made from hydroxylation and decarboxylation of tryptophan?

      Your Answer: Serotonin

      Explanation:

      Serotonin is synthesized from the essential amino acid tryptophan. The rate-limiting step is the conversion of the amino acid to 5-hydroxytryptophan by tryptophan hydroxylase. This is then converted to serotonin by the aromatic L-amino acid decarboxylase.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      2.2
      Seconds

  • Question 6 - Which of the following forms an important constituent of the brush border on...

    Correct

    • Which of the following forms an important constituent of the brush border on the microvilli of the intestinal epithelium?

      Your Answer: Hydrolases

      Explanation:

      There are certain enzymes which are part of the brush border cells including hydrolases also known as the brush border hydrolases. They perform the final step in digestion of certain nutrients.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      2.7
      Seconds

  • Question 7 - The following are synthesized in the liver EXCEPT? ...

    Correct

    • The following are synthesized in the liver EXCEPT?

      Your Answer: Cholecystokinin

      Explanation:

      The liver is responsible for the mainstay of protein metabolism, synthesis as well as degradation. It is also responsible for a large part of amino acid synthesis. The liver plays a role in the production of clotting factors as well as red blood cell production. Some of the proteins synthesized by the liver include coagulation factors I (fibrinogen), II (prothrombin), V, VII, VIII, IX, X, XI, XIII, as well as protein C, protein S and antithrombin. The liver is a major site of production for thrombopoietin, a glycoprotein hormone that regulates the production of platelets by the bone marrow. The liver also produces albumin, the most abundant protein in blood serum and angiotensinogen. Cholecystokinin, previously called pancreozymin, is synthesized and secreted by enteroendocrine cells in the duodenum

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      1.6
      Seconds

  • Question 8 - Which is true of the composition of bile in the human hepatic duct?...

    Correct

    • Which is true of the composition of bile in the human hepatic duct?

      Your Answer: Contains only actively secreted substances

      Explanation:

      Hepatic bile is an isotonic fluid and its electrolyte composition resembles that of plasma. 97% of water is found in the gallbladder bile, not hepatic duct. Hepatic bile is alkaline. The ratio of bile acids: phosphatidylcholine: cholesterol is 20:1:3. Hepatic bile contai9ns only actively secreted substances.

    • This question is part of the following fields:

      • Hepatobiliary
      • Medicine
      2.7
      Seconds

  • Question 9 - Protein digestion starts in the stomach by which enzyme? ...

    Correct

    • Protein digestion starts in the stomach by which enzyme?

      Your Answer: Pepsin

      Explanation:

      Pepsinogen is the inactive form of pepsin which is secreted by gastric chief cells and is converted to pepsin, in the presence of gastric HCL. Pepsin is a peptidase that breaks down proteins into smaller peptides.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      2
      Seconds

  • Question 10 - The Sinoatrial node in the majority of people is supplied by the? ...

    Correct

    • The Sinoatrial node in the majority of people is supplied by the?

      Your Answer: Right coronary artery

      Explanation:

      In 60% of people, the SA node is supplied by the right coronary artery branch and in 40% of the people by the left coronary artery.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      1.4
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Immunology (1/1) 100%
Medicine (10/10) 100%
Cardiovascular (3/3) 100%
Neurology (2/2) 100%
Gastrointestinal (3/3) 100%
Hepatobiliary (1/1) 100%
Passmed
Retry this test Dashboard