Description : Leukotrienes cause (A) Increase in capillary permeability (B) Aggregation of platelets (C) Bronchodilatation (D) None of these
Last Answer : Answer : A
Description : Lipo-oxygenase is required for the synthesis of (A) Prostaglandins (B) Leukotrienes (C) Thromboxanes (D) All of these
Last Answer : Answer : B
Description : Slow reacting Substance of Anaphylaxis is a mixture of (A) Prostaglandins (B) Prostacyclins (C) Thromboxanes (D) Leukotrienes
Last Answer : Answer : D
Description : Anti-inflammatory corticosteroids inhibit the synthesis of (A) Leukotrienes (B) Prostaglandins (C) Thromboxanes (D) All of these
Description : Leukotrienes: 1) Are formed from the cyclooxygenase pathway 2) Are synthesized by fibroblasts 3) Decrease vascular permeability 4) Leukotriene D4 has been identified as SRS-A which causes bronchial wall smooth muscle relaxation 5) Stimulate mucus secretion
Last Answer : Answers-5 Leukotrienes are synthesized by leucocytes.They are mediators of allergic reaction. They increase vascular permeability and attract neutrophils and eosinophils to inflammatory sites. ... stimulate mucus production, an important consideration in the pathophysiology of bronchial asthma.
Description : The mechanism of synthesis of DNA and RNA are similar to all the following ways except (A) They involve release of pyrophosphate from each nucleotide added (B) They require activated nucleotide precursor and Mg2+ (C) The direction of synthesis is (D) They require a primer
Description : Insoinic acid is the biological precursor of (A) Cytosine and Uric acid (B) Adenylve acid and Glucine floc acid (C) Orotic acid and Uridylic acid (D) Adenosine acid Thymidine
Description : The mechanism of synthesis of DNA and RNA are similar in all the following ways except (A) They involve release of pyrophosphate from each nucleotide added (B) They require activated nucleotide precursor and Mg2+ (C) The direction of synthesis is 5’ → 3’ (D) They require a primer
Description : All of the following statements about tRNA are true except (A) It is synthesized as a large precursor (B) It is processed in the nucelolus (C) It has no codons or anticodons (D) Genes for rRNA are present in single copies
Description : Heterogeneous nuclear RNA is the precursor of (A) mRNA (B) rRNA (C) tRNA (D) None of these
Description : Pyrimidine and purine nucleoside biosynthesis share a common precursor: (A) PRPP (B) Glycine (C) Fumarate (D) Alanine
Description : All the following statements about βendorphin are true except µ : (A) It is a polypeptide (B) Its precursor is pro-opio-melanocortin (C) Its receptors are represent in brain (D) Its action is blocked by morphine
Description : Immediate precursor of epinephrine is (A) Metanephrine (B) Norepinephrine (C) Dopa (D) Dopamine
Description : All the following statements about proopiomelanocortin are true except (A) It is made up of 285 amino acids (B) It is synthesised in pars intermedia and anterior lobe of pituitary gland ... ) It is the precursor of corticotropin like intermediate lobe peptide and endorphins 218 MCQs IN BIOCHEMISTRY
Last Answer : Answer : C
Description : Precursor of ACTH is (A) Cholesterol (B) Pregnenolone (C) Corticotropin (D) Pro-opiomelanocortin
Description : The precursor of testosterone is (A) Aldosterone (B) Methyl testosterone (C) Estrone (D) Pregnenolone
Description : Zymogen is a (A) Vitamin (B) Enzyme precursor (C) Modulator (D) Hormone
Description : The common precursor in the biosynthesis of triacylglycerol and phospholipids is (A) 1, 2-Diacylglycerol phosphate (B) 1-Acylglycerol 3-phosphate (C) Glycerol 3-phosphate (D) Dihydroxyacetone phosphate
Description : In the pathway leading to biosynthesis of acetoacetate from acetyl-CoA in liver, the immediate precursor of aceotacetate is (A) Acetoacetyl-CoA (B) 3-Hydroxybutyryl-CoA (C) 3-Hydroxy-3-methyl-glutaryl-CoA (D) 3-Hydroxybutyrate
Description : Which of the following intermediates of metabolism can be both a precursor and a product of glucose? (A) Lactate (B) Pyruvate (C) Alanine (D) Acetyl-CoA
Description : Cholesterol is a precursor in the biogenesis of (A) Vitamin A (B) Vitamin D (C) Vitamin E (D) None of these
Description : Precursor of Vitamin A is (A) α-Carotene (B) β-Carotene (C) γ-Carotene (D) All of these VITAMINS 121
Description : The precursor of CoA is (A) Riboflavin (B) Pyridoxamine (C) Thiamin (D) Pantothenate
Description : β-Carotene, precursor of vitamin A, is oxidatively cleaved by (A) β-Carotene dioxygenase (B) Oxygenase (C) Hydroxylase (D) Transferase
Description : Cholesterol is the precursor for the biosynthesis of (A) fatty acid (B) prostaglandins (C) bile acids (D) sphingmyelin
Description : The precursor of bile salts, sex hormones and vitamin D is (A) Diosgenin (B) Cholesterol (C) Campesterol (D) Ergosterol
Description : All the following statements about angiotensin are true except (A) Its precursor is an α2-globulin (B) Its active form is an octapeptide (C) It is a vasodilator (D) It increases the secretion of aldosterone
Description : All the following statements about pepsin are correct except (A) It is smaller than pepsinogen (B) It is formed by the action of HCl on its precursor (C) Its optimum pH is 1.0–2.0 (D) It hydrolyses the C-terminal and N-terminal peptide bonds of proteins
Description : Tryptophan could be considered as precursor of (A) Melanotonin (B) Thyroid hormones (C) Melanin (D) Epinephrine
Description : In mammalian tissues serine can be a biosynthetic precursor of (A) Methionine (B) Glycine (C) Tryptophan (D) Phenylalanine
Description : Phenylalanine is the precursor of (A) L-DOPA (B) Histamine (C) Tyrosine (D) Throxine
Last Answer : C
Description : Muscle glycogen will not serve as a precursor of blood sugar, why?
Last Answer : Glucose-6-phosphatase is absent in muscle.
Description : Eicosanoids mediate inflammation in a variety of ways. Of the following statements, which are true with regard to this? a. Eicosanoids are stored in cytoplasmic granules ... include vasodilatation, vasoconstriction, increased vascular permeability and both chemotaxis and chemoattractant inhibition
Last Answer : Answer: b, d The eicosanoids are derived from arachidonic acid (eicosatetraenoic acid) and consist of prostaglandins, thromboxanes, leukotrienes and lipoxins. The eicosanoids are not ... nervous system d. Mononuclear phagocytes release a variety of proinflammatory cytokines and growth factors
Description : Which of the following terms best describes the antagonism of leukotriene's bronchoconstrictor effect (mediated at leukotriene receptors) by terbutaline (acting a adrenoceptors) in a patient with ... ) Partial agonist (c) Physiologic antagonist (d) Chemical antagonist (e) Noncompetitive antagonist
Last Answer : Ans: C
Description : Following mediators are involved in acute inflammation except (a) Histamine (b) Leukotrienes (c) Interferons (d) Bradykinin
Description : Which of the following compounds is most likely to lower circulating levels of leukotrienes? (a) Zileuton (b) Montelukast (c) Carprofen (d) Aspirin (e) Allopurinol
Last Answer : Ans: A
Description : Cyclooxygenase-1 and –2 are responsible for (a) The synthesis of prostaglandins from arachidonate (b) The synthesis of leukotrienes from arachidonate (c) The conversion of ATP to cAMP (d) The metabolic degradation of cAMP (e) The conversion of GTP to cGMP
Description : Inflammation is a complex tissue reaction that includes the release of cytokines, leukotrienes, prostaglandins, and peptides. Prostaglandins involved in inflammatory processes are produced from arachidonic acid by (a) ... 2 (c) Glutathione - S - transferase (d) Lipoxygenase (e) Phospholipase A2
Last Answer : Ans: B
Description : Explain in brief about leukotrienes and prostaglandins Leukotrienes and prostaglandins are formed only when the mast cell undergo degranulation and enzymatic break down of phospholipids in the plasma membrane ?
Last Answer : The effects produced by them are more pronounced and long lasting than histamine. Leukotrienes mediate mucous production and bronchoconstriction. Prostaglandin D2 causes bronchoconstriction.
Description : Biologically active metabolites of arachidonic acid include all of the following EXCEPT: C A. Leukotrienes B. Thyromboxane A2 C. Complement D. Prostaglandin
Last Answer : Complement
Description : Biologically active metabolites of arachidonic acid include all of the following EXCEPT: C A. Leukotrienes (SRS) B. Thyromboxane A2 C. Complement D. None of these
Description : The most important preformed mediator of allergic reactions is/are a. Prostaglandin b. Interleukin c. Histamine d. Leukotrienes
Last Answer : c. Histamine
Description : Choose the correct statement about cysteinyl leukotrienes (LT-C4/D4): A. They produce long lasting bronchoconstriction B. They produce sustained rise in blood pressure C. They are responsible ... and sequestrating neutrophils at the site of inflammation D. Their production is inhibited by rofecoxib
Last Answer : A. They produce long lasting bronchoconstriction
Description : There are no preformed stores of the following autacoid/autacoids: A. Prostaglandins B. Leukotrienes C. Angiotensin II D. All of the above
Last Answer : D. All of the above
Description : Who remembers the precursor to video games, choose your own adventure novels?
Last Answer : I totally remember those. I thought it was amazing when goosebumps did em. Love the memories
Description : What is the meaning of the word Precursor ?
Last Answer : forerunner , forerunner, etc.
Description : Carbon skeleton produced during respiration. (Eg. `alpha`-ketoglutarate, OAA etc. intermediates) are used as precursor for biosynthesis of other molec
Last Answer : Carbon skeleton produced during respiration. (Eg. `alpha`-ketoglutarate, OAA etc. intermediates) are ... biosynthesis of other molecules in the cell.
Description : Which of the following technique is used to measure the hormones, their precursor, and their metabolic and products quantitatively in the living body
Last Answer : Which of the following technique is used to measure the hormones, their precursor, and their ... Chromatography C. Oscilloscope D. None of these