This set contains 20 multiple-choice questions (MCQs) focused on proteins and amino acids, ideal for use in an exam or test setting. The questions cover various topics, including the structure and function of proteins, biochemical properties of amino acids, and key concepts related to protein assays and associated disorders.
- Which of the following reagents are components of biuret?
- 1. copper sulfate
- 2. potassium iodide
- 3. sodium potassium tartrate
- 4. sodium hydroxide
- A. only 1 and 3 are correct
- B. only 2 and 4 are correct
- C. only 1,2, and 3 are correct
- D. 1,2,3 and 4 are correct ✅
- Which of the following diseases and conditions may cause hypoproteinemia?
- 1. severe liver damage
- 2. ulcerative colitis
- 3. glomerulonephritis
- 4. skin diseases
- A. only 1 and 3 are correct
- B. only 2 and 4 are correct
- C. only 1,2, and 3 are correct
- D. 1,2,3 and 4 are correct ✅
- In total protein determination, which of the following statements is correct?
- A. The blood should be collected with the patient in a supine position since blood samples obtained in an upright position lead to measurement of up to 10% lower TP concentration.
- B. After more than 3 mins. of venous occlusion during blood collection, the protein level may rise by up to 10%✅
- C. Due to fibrinogen, the mean total protein concentration in plasma is lower than in serum.
- D. The patient need to be in fasting state for the blood collection.
- Which of the following substances may elevate protein level?
- 1. hemolysis
- 2. x-ray contrast media
- 3. dextran
- 4. bilirubin
- A. only 1 and 3 are correct
- B. only 2 and 4 are correct
- C. only 1,2, and 3 are correct
- D. 1,2,3 and 4 are correct ✅
- Which of the following diseases and conditions may cause hyperproteinemia?
- 1. macroglobulinemia
- 2. liver cirrhosis
- 3. chronic inflammatory disease
- 4. Schistosomiasis
- A. only 1 and 3 are correct
- B. only 2 and 4 are correct
- C. only 1,2, and 3 are correct
- D. 1,2,3 and 4 are correct ✅
- All proteins are pure polypeptide chains whose molecular mass is composed of nitrogen in approximately:
- A. 6%
- B. 16% ✅
- C. 26%
- D. 36%
- Which of the following is used as the calibrator in the methods of determination for total protein?
- A. bovine serum albumin ✅
- B. serum protein
- C. plasma protein
- D. hemoglobin
- These proteins migrate in the alpha1 and alpha2 globulin band and are elevated by 50-300% in acute inflammatory conditions but are decreased in acute hepatitis, chronic active liver diseases, and protein-losing syndromes.
- A. immunoglobulins
- B. acute phase proteins ✅
- C. transerythrin-transferrin group
- D. polyclonal gammopathies
- Hypoalbuminemia may be caused by:
- 1. liver dysfunction
- 2. pregnancy
- 3. nephritic syndromes
- 4. acute phase response
- A. only 1 and 3 are correct
- B. only 2 and 4 are correct
- C. only 1,2, and 3 are correct
- D. 1,2,3 and 4 are correct ✅
- In comparison to upright position, plasma albumin concentration declines by about 15% after a supine position has been assumed for at least:
- A. 5 mins
- B. 10 mins
- C. 15 mins
- D. 20 mins✅
- Based on their electrophoretic mobility, which of the following alpha1 antitrypsin variants do not match?
- A. F: located near the anode
- B. M: medium mobility
- C. S: towards the cathode✅
- D. Z: located near the cathode
- Alpha1 antitrypsin is used in the diagnosis of:
- 1. prolonged jaundice in neonates
- 2. hepatitis of uncertain origin during infancy and early childhood
- 3. pulmonary emphysema in adults
- 4. hepatitis or liver cirrhosis of uncertain origin in adults
- A. only 1 and 3 are correct
- B. only 2 and 4 are correct
- C. only 1,2, and 3 are correct
- D. 1,2,3 and 4 are correct ✅
- Which of the following anticoagulants may cause falsely reduced alpha1 antitrypsin concentrations in the case of determination by means of radial immunodiffusion?
- 1. buffered citrate
- 2. potassium oxalate
- 3. EDTA
- 4. heparin
- A. only 1 and 3 are correct
- B. only 2 and 4 are correct
- C. only 1,2, and 3 are correct✅
- D. 1,2,3 and 4 are correct
- The Kjeldahl procedure for total protein is based upon the premise that:
- A. proteins are negatively charged
- B. the pK of proteins is the same
- C. the nitrogen content of proteins is constant ✅
- D. proteins have similar tyrosine and tryptophan content
- All of the following statements about total protein assays are true, except?
- A. refractive index of serum correlates with total protein, but is falsely high in uremia
- B. the Folin-Lowry assay is subject to interference from nonprotein reductants
- C. Turbidimetric assays are subject to positive interference from many drugs
- D. Direct UV methods are based on the absorbance of peptide bonds at 254nm. ✅
- Hyperalbuminemia is caused by:
- A. dehydration syndromes ✅
- B. Liver disease
- C. Burns
- D. Gastroenteropathy
- The term biuret reaction refers to:
- A. the reaction of phenolic groups with CuSO4
- B. coordinate bonds between Cu and carboxyl and amino groups of biuret ✅
- C. the protein error of indicator effect producing color when dyes bind protein
- D. the reaction of phosphomolybdic acid with protein.
- Which protein is an acute phase protein and a transport protein? Its function is to transport intravascular, free hemoglobin to its degradation site in the reticulo-endothelial system?
- A. haptoglobin✅
- B. ceruloplasmin
- C. hemopexin
- D. ferritin
- Which protein is important for the estimation of the extent of intravascular hemolysis if serum haptoglobin shows nonmeasurable levels?
- A. hemoglobin
- B. ceruloplasmin
- C. hemopexin ✅
- D. ferritin
- Which of the following is true about ceruloplasmin?
- 1. transport copper in plasma
- 2. deficiency is associated with Wilson’s disease
- 3. contains about 9% carbohydrate
- 4. synthesized in the liver
- A. only 1 and 3 are correct
- B. only 2 and 4 are correct
- C. only 1,2, and 3 are correct
- D. 1,2,3 and 4 are correct ✅
