Which of the following is not true of the blood-brain
barrier:
A. It is constituted by tight junctions between
the endothelial cells of brain capillaries and
the glial tissue
B. It allows passage of lipid soluble drugs into
the brain
C. It limits entry of highly ionized drugs into the brain
D. It regulates passage of substances from brain
into blood

1 Answer

Answer :

D. It regulates passage of substances from brain
into blood

Related questions

Description : Which of the following is not true of the blood-brain barrier: A. It is constituted by tight junctions between the endothelial cells of brain capillaries and the glial tissue B. It allows passage ... of highly ionized drugs into the brain D. It regulates passage of substances from brain into blood

Last Answer : D. It regulates passage of substances from brain into blood

Description : Which of the following is not true of the blood-brain barrier: A. It is constituted by tight junctions between the endothelial cells of brain capillaries and the glial tissue B. It allows passage ... of highly ionized drugs into the brain D. It regulates passage of substances from brain into blood

Last Answer : D. It regulates passage of substances from brain into blood

Description : 6 The blood-brain barrier, which restricts entry of many drugs into brain, is constituted by: A. P-glycoprotein efflux carriers in brain capillary cells B. Tight junctions between endothelial cells of brain capillaries C. Enzymes present in brain capillary walls D. All of the above

Last Answer : D. All of the above

Description : The blood-brain barrier, which restricts entry of many drugs into brain, is constituted by: A. P-glycoprotein efflux carriers in brain capillary cells B. Tight junctions between endothelial cells of brain capillaries C. Enzymes present in brain capillary walls D. All of the above

Last Answer : D. All of the above

Description : The blood-brain barrier, which restricts entry of many drugs into brain, is constituted by: A. P-glycoprotein efflux carriers in brain capillary cells B. Tight junctions between endothelial cells of brain capillaries C. Enzymes present in brain capillary walls D. All of the above

Last Answer : D. All of the above

Description : Weakly acidic drugs: A. Are bound primarily to α1 acid glycoprotein in plasma B. Are excreted faster in alkaline urine C. Are highly ionized in the gastric juice D. Do not cross blood-brain barrier

Last Answer : B. Are excreted faster in alkaline urine

Description : The blood-brain-barrier: a. contains the foot processes of astrocytes b. contains endothelial cells with tight junction c. allows transport in one direction only ie from the vascular system into the brain d. does not allow diffusion of water

Last Answer : does not allow diffusion of water

Description : The distinctive feature(s) of methadone compared to morphine is/are: A. High oral bioavailability B. High plasma protein and tissue binding C. Delayed and milder withdrawal symptoms in dependent subjects D. All of the above

Last Answer : D. All of the above

Description : The following are true about blood-brain barrier: a. it is permeable at birth b. it involves tight junction between endothelial cells and end feet processes of astrocytes c. it is absent in the posterior pituitary d. all above

Last Answer : all above

Description : Weakly acidic drugs: A. Are bound primarily to α1 acid glycoprotein in plasma B. Are excreted faster in alkaline urine C. Are highly ionized in the gastric juice D. Do not cross blood-brain barrier

Last Answer : B. Are excreted faster in alkaline urine

Description : Weakly acidic drugs: A. Are bound primarily to α1 acid glycoprotein in plasma B. Are excreted faster in alkaline urine C. Are highly ionized in the gastric juice D. Do not cross blood-brain barrier

Last Answer : B. Are excreted faster in alkaline urine

Description : The blood - brain barrier: a. is permeable to bilirubin at birth b. is formed by the tight junctions between endothlial cells and the end feet processes of astrocytes c. is permeable to glucose d. all above

Last Answer : all above

Description : The blood - brain barrier: a. is permeable to bilirubin at birth b. is formed by the tight junctions between endothlial cells and the end feet processes of astrocytes c. is permeable to glucose d. all above

Last Answer : all above

Description : Neuromuscular blocking drugs do not produce central actions because: A. They do not cross the blood-brain barrier B. Nicotinic receptors are not present in the brain C. They are sequestrated in the periphery by tight binding to the skeletal muscles D. They do not ionise at the brain pH

Last Answer : A. They do not cross the blood-brain barrier

Description : With regard to the blood retina barrier: a. the outer blood retina is formed by the retinal pigment epithelium cells and their junctions b. the blood retina barrier is typically defective in the ... fluid and anions from the extracellular space of the retina into the circulation d. all above

Last Answer : all above

Description : 05. What kind of substances can’t permeate membranes by passive diffusion? a) Lipid-soluble b) Non-ionized substances c) Hydrophobic substances d) Hydrophilic substances 06. A hydrophilic medicinal agent

Last Answer : d) Hydrophilic substances

Description : Glucose entry into the cells of the following organ/ tissue is highly dependent on the presence of insulin: A. Brain B. Liver C. Adipose tissue D. Kidney tubules

Last Answer : C. Adipose tissue

Description : X L and X C in Series

Last Answer : Inductive reactance X L and Capacitive reactance X C in series. Inductive reactance X L of value 60 ohm and Capacitive reactance X C of value 40 ohm are connected in series. 120 volts A C voltage is ... . The current will be 6 ampere. This time current will lead the voltage by 90 degree.

Description : Read the following (A - D) stetements :- (A) Tight junctions help to stop substances from leaking across a tissue (B) Adhering junctions perform cemen

Last Answer : Read the following (A - D) stetements :- (A) Tight junctions help to stop substances from leaking across a ... correct A. Four B. Three C. Two D. One

Description : The most important factor which governs diffusion of drugs across capillaries other than those in the brain is: A. Blood flow through the capillary B. Lipid solubility of the drug C. pKa value of the drug D. pH of the medium

Last Answer : A. Blood flow through the capillary

Description : The most important factor which governs diffusion of drugs across capillaries other than those in the brain is: A. Blood flow through the capillary B. Lipid solubility of the drug C. pKa value of the drug D. pH of the medium

Last Answer : A. Blood flow through the capillary

Description : 5 A nonvolatile, highly lipid soluble drug is metabolized at a rate of 15% per hour. On intravenous injection it produces general anaesthesia for 10 min. Which process is responsible for termination ... : A. Metabolism in liver B. Plasma protein binding C. Excretion by kidney D. Redistribution

Last Answer : D. Redistribution

Description : Which of the following statements regarding endothelial cells in acute inflammation are true? a. Endothelial cells are characterized by phenotypic homogeneity b. Specific patterns of receptor expression ... blood flow and leukocyte adhesion d. Endothelial cells may be capable of phagocytosis

Last Answer : Answer: b, c, d Endothelial cells are increasingly recognized to be phenotypically heterogeneous. Specific receptor molecules are expressed at various sites where they help to direct lymphocytes and ... rather, they possess the ability to direct and focus many aspects of an inflammatory event

Description : Marked redistribution is a feature of: A. Highly lipid soluble drugs B. Poorly lipid soluble drugs C. Depot preparations D. Highly plasma protein bound drugs

Last Answer : A. Highly lipid soluble drugs

Description : Marked redistribution is a feature of: A. Highly lipid soluble drugs B. Poorly lipid soluble drugs C. Depot preparations D. Highly plasma protein bound drugs

Last Answer : A. Highly lipid soluble drugs

Description : Marked redistribution is a feature of: A. Highly lipid soluble drugs B. Poorly lipid soluble drugs C. Depot preparations D. Highly plasma protein bound drugs

Last Answer : A. Highly lipid soluble drugs

Description : The following is true of cancer chemotherapy: A. Anticancer drugs increase the risk of developing leukaemias and lymphomas several years later B. All anticancer drugs are highly emetogenic C. Growth fraction of ... than any nomral tissue of the body Aim4aiims.in D. All of the above are correct

Last Answer : A. Anticancer drugs increase the risk of developing leukaemias and lymphomas several years later

Description : Streptomycin sulfate is not absorbed orally because it is: A. Degraded by gastrointestinal enzymes B. Destroyed by gastric acid C. Highly ionized at a wide range of pH values D. Insoluble in water

Last Answer : C. Highly ionized at a wide range of pH values

Description : Oxethazaine is used for anaesthetizing gastric mucosa because: A. It is not absorbed from the gastrointestinal tract B. It remains largely unionized in acidic medium C. It is highly ionized in acidic medium D. It produces no systemic effects even at high doses

Last Answer : B. It remains largely unionized in acidic medium

Description : Antiatherosclerotic effect of which class of hypolipidemic drugs may involve additional mechanisms like improved endothelial function, reduced LDL oxidation and antiinflammatory property: A. Bile acid sequestrant resins B. Statins C. Fibrates D. Nicotinic acid

Last Answer : B. Statins

Description : The cell junctions called tight, adhering and gap junctions are found in (a) connective tissue (b) epithelial tissue (c) neural tissue (d) muscular tissue

Last Answer : (b) epithelial tissue

Description : The basic structure of cell membranes (a) Is a lipid bilayer that serves as a barrier to water soluble molecules (b) Differs ultra structurally for internal and external membranes ... dispersed within a protein bilayer (d) Is visualised as bilaminar structure with transmission electron microscopy

Last Answer : Ans:(a)

Description : The following is not true of morphine: A. Its 2-glucuronide metabolite is an active analgesic B. Its active metabolite penetrates blood-brain barrier better than morphine C. Its oral: parenteral activity ratio is 1:4 D. It undergoes enterohepatic cycling

Last Answer : B. Its active metabolite penetrates blood-brain barrier better than morphine

Description : Advantages of angiotensin converting enzyme inhibitors as antihypertensive include the following except: A. They tend to reverse left ventricular hypertrophy B. Their efficacy is not reduced by nonsteroidal ... . They do not worsen blood lipid profile D. They do not impair work performance

Last Answer : B. Their efficacy is not reduced by nonsteroidal antiinflammatory drugs

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 : The ability of the cell membrane to act as a selective barrier depends upon (A) The lipid composition of the membrane (B) The pores which allows small molecules (C) The special mediated transport systems (D) All of these

Last Answer : D

Description : Which of the following statement(s) is/are correct concerning cell junctions? a. The major occluding junction is the tight junction or zonula occludens b. Tight junctions are usually located near ... adjacent cells d. Gap junctions are a type of cell junction specialized for cell communication

Last Answer : Answer: a, c, d Cell junctions are classified as occluding, anchoring, and communicating. The major occluding junction is the tight junction or zonula occludens which connects ... gap junction which is specialized for communication. This junction mediates both electrical and chemical coupling

Description : Biotransformation of drugs is primarily directed to: A. Activate the drug B. Inactivate the drug C. Convert lipid soluble drugs into nonlipid soluble metabolites D. Convert nonlipid soluble drugs into lipid soluble metabolites

Last Answer : C. Convert lipid soluble drugs into nonlipid soluble metabolites

Description : Biotransformation of drugs is primarily directed to: A. Activate the drug B. Inactivate the drug C. Convert lipid soluble drugs into nonlipid soluble metabolites D. Convert nonlipid soluble drugs into lipid soluble metabolites

Last Answer : C. Convert lipid soluble drugs into nonlipid soluble metabolites

Description : A nonvolatile, highly lipid soluble drug is metabolized at a rate of 15% per hour. On intravenous injection it produces general anaesthesia for 10 min. Which process is responsible for termination of ... : A. Metabolism in liver B. Plasma protein binding C. Excretion by kidney D. Redistribution

Last Answer : D. Redistribution

Description : A nonvolatile, highly lipid soluble drug is metabolized at a rate of 15% per hour. On intravenous injection it produces general anaesthesia for 10 min. Which process is responsible for termination of ... : A. Metabolism in liver B. Plasma protein binding C. Excretion by kidney D. Redistribution

Last Answer : D. Redistribution

Description : Compared to pork/beef insulins, the human insulins: A. Are more potent B. Have a faster kinetics of absorption and elimination C. Have longer biological action half life D. Penetrate blood-brain barrier more efficiently

Last Answer : B. Have a faster kinetics of absorption and elimination

Description : The primary action by which entacapone and tolcapone enhance the therapeutic effect of levodopa-carbidopa in parkinsonism is: A. Inhibition of levodopa methylation in the liver B. Inhibition of ... of dopamine in the brain D. Facilitation of active transport of levodopa across brain capillaries

Last Answer : A. Inhibition of levodopa methylation in the liver

Description : 1 kg of a saturated aqueous solution of a highly soluble component A at 60°C is cooled to 25°C. The solubility limits of A are (0.6 kgA/kg water) at 60°C and (0.2 kgA/kg water) at 25°C. The amount in kg of the crystals formed is: (A) 0.4 (B) 0.25 (C) 0.2 (D) 0.175

Last Answer : (C) 0.2

Description : Sulfamethoxypyridazine and other related long acting sulfonamides have now gone into disuse because (a) They have produced serious cutaneous reactions (b) They have produced high incidence of crystalluria (c) They interact with many drugs (d) They do not penetrate blood-brain barrier

Last Answer : Ans: A

Description : The following is not true of local anaesthetics: A. The local anaesthetic is required in the unionized form for penetrating the neuronal membrane B. The local anaesthetic approaches its receptor ... the resting state D. The local anaesthetic combines with its receptor in the ionized cationic form

Last Answer : C. The local anaesthetic binds to its receptor mainly when the Na+ channel is in the resting state

Description : The following are true about tight junction: a. it forms a barrier to water b. it is found in the blood-aqueous barrier of the ciliary body c. it is found in the blood-retinal barrier at the apex of the retinal pigment epithelium d. all above

Last Answer : all above

Description : Which of the following statement(s) is/are true concerning the cell plasma membrane? a. The plasma membrane is composed of amphipathic molecules b. The hydrophobic core of the lipid bilayer of the ... contribute to the cell coat d. The membrane proteins of nerve cells are highly voltage-dependent

Last Answer : Answer: a, b, d The plasma membrane defines the boundary of the cell and serves to contain and concentrate enzymes and other macromolecule constituents. The plasma membrane is ... and bear carbohydrate moieties primarily as oligosaccharide chains that contribute to the cell coat or glycocalyx