Description : Hormonal stimulation of the formation of the second messenger inositol 1,4,5 triphosphate (IP3) quickly leads to the release of which other intracellular messenger? (A) cAMP (B) Prostaglandin (C) Calcinon (D) Leukotriene
Last Answer : Answer : C
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 : The second messenger for glucocorticoids is (A) Cyclic AMP (B) Cyclic GMP (C) Inositol triphosphate (D) No second messenger is required
Last Answer : Answer : D
Description : Second messenger for glucagons is (A) Cyclic AMP (B) Diacylglycerol (C) Cyclic GMP (D) Inositol triphosphate
Description : The second messenger for PTH is (A) Cyclic AMP (B) Cyclic GMP (C) Diacylglycerol (D) Inositol triphosphate
Description : All the following statements about ACTH are true except (A) It is a tropic hormone (B) Its target cells are located in adrenal cortex (C) Its receptors are located in the cell membrane (D) Its second messenger is inositol triphosphate
Description : Inositol triphosphate is the second messenger for (A) Gastrin (B) Cholecystokinin (C) Oxytocin (D) All of these
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 : In contrast to Eukaryotic mRNA, prokaryotic mRNA is characterized by (A) Having 7-methyl guanosine triphosphate at the 5’ end (B) Being polycystronic (C) Being only monocystronic (D) Being synthesized with introns
Description : 5’-Terminus of mRNA molecule is capped with (A) Guanosine triphosphate (B) 7-Methylguanosine triphophate (C) Adenosine triphosphate (D) Adenosine diphosphate
Last Answer : Answer : B
Description : Hormone that bind to cell surface receptor and require the second messenger camp is (A) Antidiuretic hormone (B) Cholecystokinin (C) Calcitriol (D) Gastrin
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
Description : Dipalmitoyl lecithin acts as (A) Platelet activating factor (B) Second messenger for hormones (C) Lung surfactant (D) Anti-ketogenic compound
Description : Which one of the following is not a secondary messenger in hormone action? (a) cAMP (b) cGMP (c) Calcium (d) Sodium
Last Answer : d) Sodium
Description : Which does NOT occur in a cell stimulated by a steroid hormone? A) The steroid hormone enters the cell by crossing the plasma membrane. B) The hormone binds to a receptor molecule in the ... activates certain genes. E) DNA is transcribed, mRNA is translated, and the result is protein synthesis.
Last Answer : C) The second messenger cyclic AMP is stimulated by the hormone-receptor complex. D) The hormone-receptor complex binds the chromatin and activates certain genes.
Description : Which of the following hormones is NOT correctly matched with its description? A) thymosin--aids in production of T cells B) thyroxin--needed for growth and development in vertebrates ... by removing glucose into tissues E) epinephrine--released by the adrenal medulla under stressful conditions
Last Answer : D) cortisol--lowers blood glucose level by removing glucose into tissues E) epinephrine--released by the adrenal medulla under stressful conditions
Description : Why second-messenger systems are required for peptide hormones? -Biology
Last Answer : answer:
Description : Hormone receptors that stimulate cAMP production (A) are part of a complex of two proteins that transform the external signal into internal cAMP production (B) are proteins distinct and separate from those ... binding of the hormone (D) are not very specific and bind a number of different hormones
Description : The best understood intracellular messenger is cyclic AMP (cAMP). Which of the following statement(s) concerning this intracellular messenger is/are correct? a. Intracellular cyclic AMP is constantly ... of adenylate cyclase d. cAMP is the only cyclic nucleotide active as an intracellular messenger
Last Answer : Answer: a, b The prototypic intracellular messenger is cAMP. To function as a mediator, the concentration of cAMP must change rapidly. In resting cells, cAMP is continuously being degraded by ... produce cGMP. Intracellular calcium ions also serve as second messengers in a large number of cells
Description : Activated phospholipase C acts on (A) Phosphatidyl inositol-4, 5-biphosphate (B) Inositol-1, 4, 5-triphosphate (C) Protein kinase C (D) Pl-3 kinase
Description : There are two properties of the cell necessary to maintain nonequilibrium cellular composition; the first is selectivity and the second is energy conversion. Which of the following statement(s ... transported via secondary active transport include hydrogen ions, calcium, amino acids and glucose
Last Answer : Answer: c, d The selectivity of the plasma membrane, although impressive, cannot account for the nonequilibrium composition of living cells. A cell can be maintained in a nonequilibrium state only by ... to drive the transport of a second species such as protons, calcium, amino acids, or glucose
Description : All of the following statements about post-transcriptional processing of tRNA are true except (A) Introns of some tRNA precursors are removed (B) CCA is added at 3′ end (C) 7-Methylguanosine triphosphate cap is added at 5′ end (D) Some bases are methylated
Description : Post-transcriptional modification of hnRNA involves all of the following except (A) Addition of 7-methylguanosine triphosphate cap (B) Addition of polyadenylate tail (C) Insertion of nucleotides (D) Deletion of introns
Description : All of the following occur in orotic aciduria except (A) Increased synthesis of pyrimidine nucleotides (B) Increased excretion of orotic acid in urine (C) Decreased synthesis of cytidine triphosphate (D) Retardation of growth
Description : Protein kinase C is activated by (A) Cyclic AMP (B) Cyclic GMP (C) Diacyl glycerol (D) Inositol triphosphate
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 : Which of the following statements is correct in relation to the endocrine system? (a) Non-nutrient chemicals produced by the body in trace amounts that act as intercellular messenger are known as ... in the body like gastrointestinal tract, heart, kidney and liver do not produce any hormones.
Last Answer : (a) Non-nutrient chemicals produced by the body in trace amounts that act as intercellular messenger are known as hormones.
Description : Actions of 5-HT2 receptor activation are primarily mediated by: A. Increased membrane permeability to Na+ ions B. Increased formation of cAMP C. Activation of guanylyl cyclase D. Generation of inositol trisphosphate and diacyl glycerols
Last Answer : D. Generation of inositol trisphosphate and diacyl glycerols
Description : The pancreatic amylase activity is increased in the presence of (A) Hydrochloric acid (B) Bile salts (C) Thiocyanate ions (D) Calcium ions
Description : The following ions help in enzymatic transfer of phosphate from ATP to pyruvic acid: (A) Sodium (B) Calcium (C) Magnesium (D) Potassium
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 GMP acts as the second messenger for (A) Nerve growth factor (B) Atrial natriuretic factor (C) Epinephrine (D) Norepinephrine
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 : Characteristics of Vitamin D and its metabolites include which one of the following? (a) Act to decrease serum levels of calcium (b) Activation of their Vitamin D receptors increases cellular CAMP ... Vitamin D increase renal excretion of calcium (e) Vitamin D deficiency results in Pager's disease
Last Answer : Ans: C
Description : Which of the following statements are true of oxidants? A. In addition to their pathophysiologic roles in inflammation, injury, and infection, oxidants also have physiologic roles. B. Oxidants may ... involved the catalytic production of superoxide anion (O 2 ) by the enzyme xanthine oxidase.
Last Answer : Answer: ABCD DISCUSSION: Oxidants are reactive oxygen metabolites that have both physiologic and pathophysiologic roles. As potent oxidizing agents, oxidants are involved in cytochrome P ... leukocyte infiltration and activation, causing further tissue damage by the release of cytotoxic proteases
Description : Adenosine Triphosphate (ATP) is (a) an enzyme (b) a protein (c) a hormone (d) a molecule with high energy bonds
Last Answer : Ans:(d)
Description : Which of the following does not act interacellularly to produce physiologic effects a. Triiodothyronine b. Inositol triphosphate c. Aldosterone d. Cyclic AMP e. Doapamine
Last Answer : Doapamine
Description : The chemiosmotic coupling hypothesis of oxidative phosphorylation proposes that adenosine triphosphate (ATP) is formed because (a) a proton gradient forms across the inner membrane (b) there is a ... mitochondrial proteins (d) ADP is pumped out of the matrix into the intermembrane space.
Last Answer : (a) a proton gradient forms across the inner membrane
Description : Mitochondria can be considered the ____________of the cell because they generate an enormous amount of cellular adenosine triphosphate (ATP) to fuel the cell.
Last Answer : “Power plant” or “Power house”
Description : The use and transfer of energy in all cells involves the same compound, ATP. The letters ATP stand for the chemical: a) atrophine trichloride b) aluminum trioxide c) adenosine triphosphate d) none of the above
Last Answer : ANSWER: C -- ADENOSINE TRIPHOSPHATE
Description : In the metallurgy of iron, when limestone is added to the blast furnace,the calcium ions end up in
Last Answer : In the metallurgy of iron, when limestone is added to the blast furnace,the calcium ions end up ... B. Gangue C. Metallic calcium D. Calcium Carbonate
Description : Do the positive charges of calcium ions and sodium ions make these ions more likely to move into or out of the cell?
Last Answer : Need answer
Description : How many chloride ions are in calcium chloride?
Last Answer : The formula unit for calcium chloride is CaCl2. There are two chloride ions in one formula unit of calcium chloride. We can also say that there are two moles chloride ions in one mole of CaCl2.
Description : A striking feature of living cells is a marked difference between the composition of the cytosol and the extracellular milieu. Which of the following statement(s) concerning the mechanisms of maintenance ... d. The selectivity of cell membranes relates only to ions and not organic compounds
Last Answer : Answer: a The survival of the cell requires that cytosolic composition be maintained within narrow limits, despite the constant influx of nutrients and the simultaneous outflow of waste. A ... be altered drastically as a result of regulatory or signaling processes that occur within the cell
Description : (3) Detergents give lather even with hard water Explanation: Soaps are made of materials found in nature. Detergents are synthetic a big drawback of washing with soap is that the minerals in water ... ions in hard water to create an insoluble residue that can clog drains and stick to clothing.
Last Answer : What is the objective of the 'Kyoto Protocol'? (1) To abolish child labour (2) To eliminate nuclear weapons (3) To increase ground water levels (4) To reduce greenhouse gases
Description : (3) Detergents give lather even with hard water Explanation: Soaps are made of materials found in nature. Detergents are synthetic. a big drawback of washing with soap is that the minerals in water ... ions in hard water to create an insoluble residue that can clog drains and stick to clothing.
Last Answer : Cement is usually a mixture of – (1) Calcium silicate and calcium alurninate (2) Calcium silicate and calcium ferrate (3) Calcium aluminate and calcium ferrate (4) Lime stone and silicon dioxide
Description : The two metal ions that cause hardness to water are: (1) Calcium, Magnesium (2) Sodium, Calcium (3) Sodium, Potassium (4) Sodium, Magnesium
Last Answer : (1) Calcium, Magnesium Explanation: Calcium and magnesium ion cause hardness of water.