Description : Phospholipid acting as surfactant is (A) Cephalin (B) Phosphatidyl inositol (C) Lecithin (D) Phosphatidyl serine
Last Answer : Answer : C
Description : Which of the following statement(s) is/are correct concerning the immunoinflammatory response to shock? a. The anaphylactoxins, C3a and C5a, are products of activation of only the classical pathway ... effects d. Platelet-activating factor can be released by both circulating and fixed tissue cells
Last Answer : Answer: d Inflammatory mediators have recently been recognized as playing a significant role in the clinical manifestations and progression of shock and the development ... increased pulmonary vascular resistance, bronchoconstriction, peripheral vasodilatation, and increased vascular permeability
Description : Platelet activating factor is: a. Generated by the action of phospholipase A2 on membrane phospholipids b. Antiinflammatory in most of its actions c. Synthesized by endothelial and other cells d. Exerts a variety of biologic effects which are platelet-independent
Last Answer : Answer: a, c, d Like the eicosanoids, platelet-activating factor (PAF) is not stored in cells but is rapidly produced during inflammation. PAF exerts a variety of biologic effects ... and LTB4. There is considerable overlap and redundancy in the effects produced by PAF and eicosanoids
Description : Which of the following statements regarding cytokines is incorrect? A. Cytokines act directly on target cells and may potentiate the actions of one another. B. Interleukin 1 (IL-1) ... organ dysfunction syndrome because of its multiple actions and the secondary cascades that it stimulates.
Last Answer : Answer: C DISCUSSION: Cytokines are soluble peptide molecules that are synthesized and secreted by a number of cell types in response to injury, inflammation, and infection. Cytokines, which ... is thought to play a central role in the stress response, particularly in response to endotoxemia
Description : All of the following are true regarding platelet-activating factor (PAF) EXCEPT: C A. Induces platelet aggregation B. Stimulates platelet secretion C. It is a preformed molecule present in various cells D. None of these
Last Answer : It is a preformed molecule present in various cells
Description : The following are true about chemicals involved in allergic reaction: a. thromboxane -leukocyte activation b. prostaglandin-2 - vasodilatation c. platelet-activating factor - leukocyte activation d. heparin - augments inactivation of prostaglandins
Last Answer : prostaglandin-2 - vasodilatation
Description : Extract of the following plant has platelet activating factor (PAF) antagonistic activity and is claimed to benefit cognitive disorders due to cerebral ischaemia: A. Ginkgo biloba B. Claviceps purpurea C. Amanita muscaria D. Artemisia annua (p. 440) 33.12 3 3 . 1 2 A Aim4aii
Last Answer : A. Ginkgo biloba
Description : The following class(es) of drugs are clinically beneficial in bronchial asthma: A. Histamine H1 receptor antagonists B. Platelet activating factor (PAF) antagonists C. Leukotriene ( cys LT1) receptor antagonists D. All of the above
Last Answer : C. Leukotriene ( cys LT1) receptor antagonists
Description : The actions of platelet activating factor include the following except: A. Increased capillary permeability B. Bronchodilatation C. Vasodilatation D. Erosion of gastric mucosa
Last Answer : B. Bronchodilatation
Description : Prolonged airway hyperreactivity is characteristically caused by: A. Histamine B. Prostaglandin E2 C. Platelet activating factor D. Bradykinin
Last Answer : C. Platelet activating factor
Description : Montelukast blocks the action of the following autacoid: A. Prostacyclin B. Platelet activating factor C. Leukotriene B4 D. Leukotriene C4/D4
Last Answer : D. Leukotriene C4/D4
Description : Low doses of aspirin prolong bleeding time by selectively inhibiting synthesis of the following mediator in the platelets: A. Thromboxane A2 B. 5-Hydroxytryptamine C. Platelet activating factor D. Prostacyclin
Last Answer : A. Thromboxane
Description : Dysmenorrhoea is often associated with excess production of the following autacoid by the endometrium: A. Bradykinin B. Prostaglandin C. Platelet activating factor D. 5-Hydroxytryptamine
Last Answer : B. Prostaglandin
Description : Cyclic GMP acts as the second messenger for (A) Nerve growth factor (B) Atrial natriuretic factor (C) Epinephrine (D) Norepinephrine
Last Answer : Answer : B
Description : How does steroid hormone influence the cellular activities? (a) Using aquaporin channels ‘as second messenger’ (b) Changing the permeability of the cell membrane (c) Binding to DNA and forming a gene-hormone complex (d) Activating cyclic AMP located on the cell membrane
Last Answer : (c) Binding to DNA and forming a gene-hormone complex
Description : All the following hormones use cAMP as a second messenger except (A) Estrogen (B) FSH (C) Luteinizing (D) Glucagon
Last Answer : Answer : A
Description : One of the following is not used as a second messenger by hormones: (A) mRNA (B) cAMP (C) Calcium ions (D) Myoinisotol 1, 4, 5 triphosphate
Description : The second messenger for many hormones is (A) ATP (B) cyclic AMP (C) cGMP (D) UTP HORMONE METABOLISM 227
Description : All the following statements about steroid hormones are true except (A) They are hydrophobic (B) They require carriers to transport them in circulation (C) Their receptors are intracellular (D) They require cyclic AMP as second messenger
Last Answer : Answer : D
Description : Cell regulation can be thought of as the effector side of cell communication. Most commonly cell regulation occurs by means of extracellular chemical messengers. Which of the following statement(s ... d. Most hormones, local mediators, and neurotransmitters readily cross the cell plasma membrane
Last Answer : Answer: b, c Depending on how the extracellular messenger arrives, cell regulation can be classified as paracrine, endocrine, or neurocrine. In paracrine regulation, a chemical messenger ... , local mediators, and neurotransmitters are water-soluble and cannot readily cross the plasma membrane
Description : Some hormones produce their intracellular effects by activating (A) Phospholipae A1 (B) Phospholipase B (C) Phospholipase C (D) All of these
Description : All the following statements about TSH are true except (A) It is a tropic hormone (B) It acts on para-follicular cells of thyroid glands (C) Its receptors are membrane-bound (D) Its second messenger is cyclic AMP
Description : Cyclic AMP acts as the second messenger for all of the following except (A) Oxytocin (B) TSH (C) ACTH (D) FSH 216 MCQs IN BIOCHEMISTRY
Description : Cyclic AMP acts as the second messenger for (A) ADH (B) Glucagon (C) Calcitonin (D) All of these
Description : What common product acts as a surfactant, poking holes in cell membranes? a. Alcohol Sanitizer b. Soap c. Phenol d. Betadine
Last Answer : b. Soap
Description : Why second-messenger systems are required for peptide hormones? -Biology
Last Answer : answer:
Description : With regard to membrane receptors for hormones: a. they are often glycoproteins b. they are important for hormones made up of steroid c. those for insulin exhibit an intrinsic protein kinase activity d. glucagon uses calcium as a second messenger
Last Answer : they are often glycoproteins
Description : Carboxymethyl cellulose (CMC) is added in detergents to act as a/an (A) Surfactant (B) Builder (C) Optical brightening agent (D) Anti soil redeposition agent
Last Answer : (D) Anti soil redeposition agent
Description : Methyldopa lowers BP by: A. Inhibiting dopa decarboxylase in adrenergic nerve endings B. Generating α-methyl noradrenaline in brain which reduces sympathetic tone C. Generating α-methyl ... as a false transmitter in peripheral adrenergic nerve endings D. Activating vascular dopamine receptors
Last Answer : B. Generating α-methyl noradrenaline in brain which reduces sympathetic tone
Description : A pheromone is A) an endorphin released within the anterior pituitary. B) a growth factor related to the production of tumors. C) a product of a neurosecretory cell that acts on ... ) a regulatory hormone that stimulates or inhibits the release of hormones produced by other endocrine glands.
Last Answer : D) a chemical released by one animal to affect the behavior of another animal.
Description : A ketogenic amino acid among the following is (A) Leucine (B) Serine (C) Threonine (D) Proline
Description : One of the following amino acid is solely ketogenic: (A) Lysine (B) Alanine (C) Valine (D) Glutamate
Description : All followings are ketogenic aminoacids except (A) Leucine (B) Isoleucine (C) Phenyl alanine (D) Glycine
Description : In metabolic point of view, amino acids are classified as (A) Glycogenic (B) Ketogenic (C) Glycogenic or Ketogenic (D) All of these
Description : A ketogenic amino acid is (A) Valine (B) Cysteine (C) Leucine (D) Threonine
Description : Which amino acids are both ketogenic and glucogenic?
Last Answer : Tyrosine and tryptophan.
Description : Name a purely ketogenic amino acid. (P
Last Answer : Leucine.
Description : What is the basis of classification of amino acids into ketogenic and glucogenic?
Last Answer : Ketogenic amino acids enter into the metabolic pathway of fats, while glucogenic amino acids enter the pathway of glucose metabolism.
Description : True statements regarding eicosanoids include which of the following? A. Prostaglandins and thromboxanes are synthesized via the cyclo-oxygenase pathway. B. The vasoconstricting, platelet-aggregating, ... prostaglandins have a short circulation half-life and exert most of their effects locally.
Last Answer : Answer: ABD DISCUSSION: The eicosanoids are a group of compounds arising from the metabolism of arachidonic acid. The prostaglandins and thromboxanes are synthesized via the cyclo-oxygenase ... effects and may be involved in the physiologic responses associated with anaphylactic and septic shock
Description : The action of aspirin that results in its greater efficacy as an antithrombotic (anti-platelet) drug is its ability to (a) Inhibit lipoxygenase as well as cyclooxygenase (b) Selectively inhibit ... I (c) Inhibit leukocyte migration (d) Promote uric acid excretion (e) Acetylate cyclooxygenase
Last Answer : Ans: E
Description : Thromboxane A2(TXA2): a. is derived from the membrane phospholipid b. its production is decreased by non-steroidal anti-inflammatory drugs c. causes platelet aggregation d. all above
Last Answer : all above
Description : When choline of lecithin is replaced by ethanolamine, the product is (A) Spingomyelin (B) Cephalin (C) Plasmalogens (D) Lysolecithin
Description : Which of the following is not a phospholipids? (A) Lecithin (B) Plasmalogen (C) Lysolecithin (D) Gangliosides
Description : Phospholipase A2 is an enzyme which removes a fatty acid residue from lecithin to form (A) Lecithin fragments (B) Phosphotidic acid (C) Glyceryl phosphate (D) Lysolecithin
Description : Lysolecithin is formed from lecithin by the action of (A) Phospholipase A1 (B) Phospholipase A2 (C) Phospholipase C (D) Phospholipase D
Description : LCAT is (A) Lactose choline alamine transferse (B) Lecithin cholesterol acyl transferase (C) Lecithin carnitine acyl transferase (D) Lanoleate carbamoyl acyl transferase
Description : Which one of the following is not a phospholipid? (A) Lecithin (B) Plasmalogen (C) Lysolecithin (D) Gangliosides
Description : Lecithin contains a nitrogenous base named as (A) Ethanolamine (B) Choline (C) Inositol (D) All of these
Description : Activated lecithin cholesterol acyl transferase is essential for the conversion of (A) VLDL remnants into LDL (B) Nascent HDL into HDL (C) HDL2 into HDL3 (D) HDL3 into HDL2
Description : Lysolecithin is formed from lecithin by removal of (A) Fatty acid from position 1 (B) Fatty acid from position 2 (C) Phosphorylcholine (D) Choline