Tuesday 27 May 2014

VPTAC Sample Paper for Pharmacy competitive examination, MCQ (With Explanation )-3

1. ANATOMY AND PHYSIOLOGY - TYROSINE - is a/an a) amino acid and protein b) anti-biotic c) glycoside d) a fibrous tissue .
Ans 1. A, It is a non-essential amino acid with a polar side group. Tyrosine is a precursor to neurotransmitters and increases plasma neurotransmitter levels (particularly dopamine and norepinephrine) but has little if any effect on mood. The effect on mood is more noticeable in humans subjected to stressful conditions (see below).

A number of studies have found tyrosine to be useful during conditions of stress, cold, fatigue,loss of a loved one such as in death or divorce, prolonged work and sleep deprivation, with reductions in stress hormone levels, reductions in stress-induced weight loss seen in animal trials, improvements in cognitive and physical performance seen in human trials; however, because tyrosine hydroxylase is the rate-limiting enzyme, effects are less significant than those of L-DOPA.


2. ALVEOLI - are ___sacs. a) air b) blood c) lymph d) cerebro-spinal fluid .





Ans 2. A, An alveolus is an anatomical structure that has the form of a hollow cavity. Found in the lung parenchyma, the pulmonary alveoli are the terminal ends of the respiratory tree, which outcrop from either alveolar sacs or alveolar ducts, which are both sites of gas exchange with the blood as well. Alveoli are particular to mammalian lungs. Different structures are involved in gas exchange in other vertebrates. The alveolar membrane is the gas-exchange surface. Carbon dioxide rich blood is pumped from the rest of the body into the alveolar blood vessels where, through diffusion, it releases its carbon dioxide and absorbs oxygen.

3. ANERGY - is a ___disorder. a) organic disorder b) immunological disorder c) speech disorder  d) sleep disorder .
 
Ans 3.B, Anergy is a term in immunobiology that describes a lack of reaction by the body's defense mechanisms to foreign substances, and consists of a direct induction of peripheral lymphocyte tolerance. An individual in a state of anergy often indicates that the immune system is unable to mount a normal immune response against a specific antigen, usually a self-antigen. Lymphocytes are said to be anergic when they fail to respond to their specific antigen. Anergy is one of three processes that induce tolerance, modifying the immune system to prevent self-destruction (the others being clonal deletion and immunoregulation).


4. CHLORPROMAZINE - is a/an a) anti-coagulant b) stimulant c) tranquilliser d) anodyne .
 
Ans 4. C, Chlorpromazine is a dopamine antagonist of the typical antipsychotic class of medications possessing additional antiadrenergic, antiserotonergic, anticholinergic and antihistaminergic properties used to treat schizophrenia.

Chlorpromazine is classified as a low-potency typical antipsychotic and in the past was used in the treatment of both acute and chronic psychoses, including schizophrenia and the manic phase of bipolar disorder as well as amphetamine-induced psychoses. Low-potency antipsychotics have more anticholinergic side effects such as dry mouth, sedation and constipation, and lower rates of extrapyramidal side effects, while high-potency antipsychotics (such as haloperidol) have the reverse profile.

5. Cushing's disease - may lead to a) anorexia b) difficult breathing c) obesity d) deafness .
 
Ans 5. C, Cushing's syndrome describes the signs and symptoms associated with prolonged exposure to inappropriately high levels of the hormone cortisol. This can be caused by taking glucocorticoid drugs, or diseases that result in excess cortisol, adrenocorticotropic hormone (ACTH), or CRH levels.

Cushing's disease refers to a pituitary-dependent cause of Cushing's syndrome: a tumor (adenoma) in the pituitary gland produces large amounts of ACTH, causing the adrenal glands to produce elevated levels of cortisol. It is the most common non-iatrogenic cause of Cushing's syndrome, responsible for 70% of cases excluding glucocorticoid related cases. An easy way to distinguish Cushing's syndrome (primary hypercortisolism, specifically) from Cushing's disease is that the measured ACTH levels are lower in the former. The decrease in ACTH is due to increased negative feedback of cortisol on the hypothalamus and anterior pituitary.

This pathology was described by Harvey Cushing in 1932.The syndrome is also called Itsenko-Cushing syndrome,hyperadrenocorticism or hypercorticism.

Cushing's syndrome is not confined to humans and is also a relatively common condition in domestic dogs and horses. It also occurs in cats, however, rarely.

Symptoms include rapid weight gain, particularly of the trunk and face with sparing of the limbs (central obesity). Common signs include the growth of fat pads along the collarbone, on the back of the neck or "buffalo hump" and on the face "moon facies". Other symptoms include hyperhidrosis (excess sweating), telangiectasia (dilation of capillaries), thinning of the skin (which causes easy bruising and dryness, particularly the hands) and other mucous membranes, purple or red striae (the weight gain in Cushing's syndrome stretches the skin, which is thin and weakened, causing it to hemorrhage) on the trunk, buttocks, arms, legs or breasts, proximal muscle weakness (hips, shoulders), and hirsutism (facial male-pattern hair growth), baldness and/or extremely dry and brittle hair. In rare cases, Cushing's can cause hypocalcemia. The excess cortisol may also affect other endocrine systems and cause, for example, insomnia, inhibited aromatase, reduced libido, impotence in men, amenorrhoea/oligomenorrhea and infertility in women due to elevations in androgens. Studies have also shown that the resultant amenorrhea is due to hypercortisolism, which feeds back onto the hypothalamus resulting in decreased levels of GnRH release.


6. Cushing's disease - may result from the malfunctioning of ___ gland. a) adrenal gland b) prostate gland c) pituitary gland d) thyroid gland .
 
Ans 6. A, Cushing's disease refers to a pituitary-dependent cause of Cushing's syndrome: a tumor (adenoma) in the pituitary gland produces large amounts of ACTH, causing the adrenal glands to produce elevated levels of cortisol. It is the most common non-iatrogenic cause of Cushing's syndrome, responsible for 70% of cases excluding glucocorticoid related cases. An easy way to distinguish Cushing's syndrome (primary hypercortisolism, specifically) from Cushing's disease is that the measured ACTH levels are lower in the former. The decrease in ACTH is due to increased negative feedback of cortisol on the hypothalamus and anterior pituitary.


7. DEXAMETHASONE - is a) anti-coagulant b) vasodilater c) steroid d) none .

Ans 7. C, Dexamethasone is a potent synthetic member of the glucocorticoid class of steroid drugs that has anti-inflammatory and immunosuppressant effects. It is 25 times more potent than cortisol in its glucocorticoid effect, while having minimal mineralocorticoid effect.

8. DIMENHYDRINATE - is a) antiemetic b) antihistamine c) both d) none .

Ans 8. C, Dimenhydrinate is an over-the-counter drug used to prevent nausea and motion sickness. It is most commonly prepared as tablets, although it is also available in liquid form and in suppositories. Dimenhydrinate is a combination of two drugs: diphenhydramine and 8-chlorotheophylline, a chlorinated derivative of theophylline.

Dimenhydrinate is primarily used for nausea and vomiting.
Diphenhydramine is the primary constituent of dimenhydrinate and dictates the primary effect. The main difference relative to pure diphenhydramine is a lower potency due to being combined with 8-chlorotheophylline. 50 mg of dimenhydrinate contains 27.2 mg of diphenhydramine.

8-Chlorotheophylline was added in order to counteract drowsiness. Theophylline is very closely related to caffeine and theobromine, mild central nervous system stimulants. It was thought by scientists that by combining the antiemetic effects of diphenhydramine with a stimulant, the extreme drowsiness induced by the former could be mitigated somewhat by the latter. The sedation caused by diphenhydramine, however, is substantially stronger than the stimulation caused by 8-chlorotheophylline, so the overall effect is still mostly sedating.


9. GONADS - can be found in a) males b) females c) both d) only in adult males .

Ans 9. C, The gonad is the organ that makes gametes. The gonads in males are the testes, and the gonads in females are the ovaries. The product, gametes, are haploid germ cells. For example, spermatozoon and egg cells are gametes.

10. Gonads - produce ___ cells. a) brain cells b) red blood cells c) white blood cells
d) sex cells .
Ans 10.D