DI-DCO Solved Exam Paper with Explanation (RAJASTHAN) . 2012 Part-3

Q.31 Male fern is collected during

a) Autumn     b) Late autumn    c) Summer  d) After Summer

Ans 31. B 

COMMON NAMES:
Commonly known as male fern, this plant is also known as Dryopteris, Wood Fern, Bear's-paw, Shield Fern, Sweet Brake, Knotty Brake and Buckler Fern.


LATIN NAME:
Dryopteris filixmas

HISTORY:
This plant is a member of the fern family, and has a vast dispersion throughout most of the Northern hemisphere of the planet, with the highest species diversity in the region of eastern Asia. Male Fern is quite possibly the most powerful traditional remedy for tapeworm ever documented in the history of medicine.


HERBAL PROPERTIES AND USES:
Male fern is revered for its oils. Medicinal oils are extracted from the plants rhizome. In ancient Greek culture, it was used as a vermifuge, and for expelling intestinal worms.

HARVESTING:
The male fern is harvested in late autumn, winter or early spring. When the fronds lie down, the plant is ready to be harvested.


DRYING METHODS / YIELD:
Only collect the older fronds. For medicinal purposes collect a rhizome which is between 3 and 6 inches long, and those which are 1 1/2 to 2 inches or more wide. Before drying the plant, first remove any scales, dead portions and roots, as it is only optimal to dry the lower vibrant portion attached to the rhizome. Clean off any remaining soil and cut in half lengthwise and dried either in the sun, or via artificial means. Used with ether, the Male Fern gives off a dark green, liquid oil. Five well-dried fern fronds can be macerated in 200 milliliters of olive oil for a healing massage oil.

PRESERVATION / PACKAGING METHODS:
After cleaned and thoroughly dried, store immediately in airtight boxes or glass jars.


ESSENTIAL OIL USE:
The main medicinal component of the male fern comes from its oil. The oil is used as an anthelmintics against tapeworm, as well as powerful purgative. The roots were also used traditionally as a healing salve for wounds, as well as a cure for rickets in the young.

PLANT CHEMICALS:
Male fern contains tannis, filicin, filixid acid, phloroglucin derivatives as well as trace amounts of some essential oils.

Q.32 When 0.1 M HCl is titrated with 0.1 M sodium hydroxide using indicator, which type of

error occurs?

a) Hydrogen error       b) Hydroxyl error        c) Acidic error             d) Alkaline error

Ans 32. D  The Alkaline error. The ordinary glass electrode becomes somewhat sensitive to alkali metal ions and gives low readings at pH values greater than 9. It should be noted that a greater tolerance (to pH 11 to 12 ) is achieved with membranes in which lithium and barium have replaced sodium and calcium to some extent.

 OR

  

Alkali error range - at low concentration of hydrogen ions (high values of pH) contributions of interfering alkali metals (like Li, Na, K) are comparable with the one of hydrogen ions. In this situation dependence of the potential on pH become non-linear.

The effect is usually noticeable at pH > 12, and concentrations of lithium or sodium ions of 0.1 moles per litre or more. Potassium ions usually cause less error than sodium ions.

Acidic error range – at very high concentration of hydrogen ions (low values of pH) the dependence of the electrode on pH becomes non-linear and the influence of the anions in the solution also becomes noticeable. These effects usually become noticeable at pH < -1.

There are different types of pH glass electrode, some of them have improved characteristics for working in alkaline or acidic media. But almost all electrodes have sufficient properties for working in the most popular pH range from pH = 2 to pH = 12. Special electrodes should be used only for working in aggressive conditions.
Most of text written above is also correct for any ion-exchange electrodes.

Q.33 In Glass electrode, platinum wire is inserted in which of the following solution

a) 0.1 M Hydrochloric acid                b) 0.1 M Mercuric chloride

c) 0.1 M Potassium chloride              d) 0.1 M Potassium Bromide

Ans 33. A 

  

A glass electrode is a type of ion-selective electrode made of a doped glass membrane that is sensitive to a specific ion. It is an important part of the instrumentation for chemical analysis and physico-chemical studies. In modern practice, widely used membranous ion-selective electrodes (ISE, including glasses) are part of a galvanic cell. The electric potential of the electrode system in solution is sensitive to changes in the content of a certain type of ions, which is reflected in the dependence of the electromotive force (EMF) of galvanic element concentrations of these ions.

This protocol covers all combination electrodes and electrode pairs consisting of a glass/pH indicator and a Ag/AgCl reference with 3M KCl salt-bridge isolution.

Instrumentation and reagents

• All pH meters and all titrators that can be operated independently as pH meters may be used. 
• Standard pH buffered solutions, minimum of two must be used.
   

Q.34 Absorption maxima goes to longer wavelength is called

a) Hypochromic shift      b) Hyperchromic shift        

c) Blue shift                    d) Red shift

Ans. D  Redshift happens when light or other electromagnetic radiation from an object is increased in wavelength, or shifted to the red end of the spectrum.

Blueshift  is any decrease in wavelength (increase in frequency); the opposite effect is referred to as redshift.

Often transitions are localized in specific bonds or functional groups within a molecule.

Q.35 Xenon arc lamp is source of

a) Spectrofluoremeter             b) IR Spectrometer c) UV-Visible Spectrophotometer   d) MNR3

Ans 35.  A  Spectrofluorometer is an instrument which takes advantage of fluorescent properties of some compounds in order to provide information regarding their concentration and chemical environment in a sample. A certain excitation wavelength is selected, and the emission is observed either at a single wavelength, or a scan is performed to record the intensity versus wavelength, also called an emission spectra.

A fluorometer or fluorimeter is a device used to measure parameters of fluorescence: its intensity and wavelength distribution of emission spectrum after excitation by a certain spectrum of light. These parameters are used to identify the presence and the amount of specific molecules in a medium. Modern fluorometers are capable of detecting fluorescent molecule concentrations as low as 1 part per trillion.

Sources for fluorometers are often dependant on the type of sample being tested. Among the most common source for fluorometers is the low-pressure mercury lamp. This provides many excitation wavelengths, making it the most versatile. However, this lamp is not a continuous source of radiation. The xenon arc lamp is used when a continuous source of radiation is needed. Both of these sources provide a suitable spectrum of ultraviolet light that induces chemiluminescence. These are just two of the many possible light sources.
Glass and silica cells are often the vessels in which the sample is placed. The scientist must be very careful to not leave fingerprints or any other sort of mark on the outside of the cell.
Fluorimetry is widely used by the dairy industry to verify whether pasteurization has been successful. This is done using a reagent which is hydrolysed to a fluorophore and phosphoric acid by alkaline phosphatase in milk. If pasteurization has been successful then alkaline phosphatase will be entirely denatured and the sample will not fluoresce. This works because pathogens in milk are killed by any heat treatment which denatures alkaline phosphatase.

Q.36 What is unit of chemical shift?

a) Centimeter                          b) cm^-1                         c) Part per million        d) Cycle per second

Ans 36. C  In nuclear magnetic resonance (NMR) spectroscopy, the chemical shift is the resonant frequency of a nucleus relative to a standard. Often the position and number of chemical shifts are diagnostic of the structure of a molecule. Chemical shifts are also used to describe signals in other forms of spectroscopy such as photoemission spectroscopy.
Some atomic nuclei possess a magnetic moment (nuclear spin), which gives rise to different energy levels and resonance frequencies in a magnetic field. The total magnetic field experienced by a nucleus includes local magnetic fields induced by currents of electrons in the molecular orbitals (note that electrons have a magnetic moment themselves). The electron distribution of the same type of nucleus (e.g. ¹H, ¹³C, ¹⁵N) usually varies according to the local geometry (binding partners, bond lengths, angles between bonds, ...), and with it the local magnetic field at each nucleus.
Chemical shift δ is usually expressed in parts per million (ppm) by frequency, because it is calculated from:

Q.37 In Polarography, diffusion current is effected by

a) Nernest equation                       b) Ilkovic equation       

c) Handerson equation                  d) Gram equation

Ans 37. B 

Ilkovic equation is a relation used in polarography relating the diffusion current (i_d) and the concentration of the depolarizer (c), which is the substance reduced or oxidized at the dropping mercury electrode. The Ilkovic equation has the form

  

Where k is a constant which includes Faraday constant, π and the density of mercury, and has been evaluated at 708 for max current and 607 for average current, D is the diffusion coefficient of the depolarizer in the medium (cm²/s), n is the number of electrons exchanged in the electrode reaction, m is the mass flow rate of Hg through the capillary (mg/sec), and t is the drop lifetime in seconds, and c is depolarizer concentration in mol/cm³.

The equation is named after the scientist who derived it, the Slovak chemist, Dionýz Ilkovič 1907-1980).

Q.38 Parathyroid gland regulates absorption of calcium. Which of the following is used in

hypoparathyrodism

a) Estrogen                              b) Liothyroxine           c) Prednisolone           d) Dihydrotachysterol

Ans 38. D The major function of the parathyroid glands is to maintain the body's calcium level within a very narrow range, so that the nervous and muscular systems can function properly.

Parathyroid hormone (PTH, also known as parathormone) is a small protein that takes part in the control of calcium and phosphate homeostasis, as well as bone physiology. Parathyroid hormone has effects antagonistic to those of calcitonin.

• Calcium. PTH increases blood calcium levels by stimulating osteoclasts to break down bone and release calcium. PTH also increases gastrointestinal calcium absorption by activating vitamin D, and promotes calcium conservation (reabsorption) by the kidneys.
• Phosphate. PTH is the major regulator of serum phosphate concentrations via actions on the kidney. It is an inhibitor of proximal and also distal tubular reabsorption of phosphorus. Through activation of Vitamin D the absorption of Phosphate is increased.

Hypoparathyroidism is decreased function of the parathyroid glands with underproduction of parathyroid hormone. This can lead to low levels of calcium in the blood, often causing cramping and twitching of muscles or tetany (involuntary muscle contraction), and several other symptoms.

Currently, treatment of patients with hypoparathyroidism involves correcting the hypocalcemia by administering calcium and vitamin D.

Dihydrotachysterol (DHT) is a synthetic vitamin D analog activated in the liver that does not require renal hydroxylation like vitamin D₂ (ergocalciferol) and vitamin D₃ (cholecalciferol). DHT has a rapid onset of action (2 hours), a shorter half-life, and a greater effect on mineralization of bone salts than does vitamin D.

Q.39 Which of the following drug is used in acute attacks of gout?

a) Cholchicine                         b) Probenecid              c) Sulfinpyrazone        d) Allopurinol

Ans 39. A  
Treatment: Acute Gout Attack

Acute attacks of gout and long-term treatment of gout and hyperuricemia require different approaches. Treatment usually involves medication. After the first attack, some health care providers advise their patients to keep a supply of medications on hand so that self-medication can begin at the first sign of symptoms of a second acute attack. There are also specific treatments for conditions associated with gout, including uric acid nephropathy and uric acid nephrolithiasis.

Many patients do not require medications. During the period between gout attacks, patients are advised to avoid foods high in purines and to maintain a healthy weight. Patients should also avoid alcohol and reduce any stress.

Drug treatments for acute attacks of gout are aimed at relieving pain and reducing inflammation. They should be started as early as possible.

Medications used in the treatment of gout include:

• NSAIDs (nonsteroidal anti-inflammatory drugs)
• Colchicine
• Corticosteroids

Colchicine

Colchicine is a derivative of the autumn crocus (also called the meadow saffron). It has been used against gout attacks for centuries. It is highly effective, although it is no longer the first drug of choice because of its frequent, unpleasant, and sometimes very serious side effects.

Colchicine may be given to a healthy adult within 48 hours of an attack. It should not be used by elderly patients or those with kidney, liver, or bone marrow disorders. It can also affect fertility and should not be used during pregnancy. The drug can cause gastrointestinal side effects at high dose, including nausea, vomiting, diarrhea, and abdominal cramps. Low doses do not pose as high a risk for gastrointestinal symptoms, and can prevent further attacks, including attacks in patients who are starting anti-hyperuricemic therapies.

Colchicine may be taken by mouth or given by an intravenous line. Those who take it by mouth need doses every hour until either symptoms improve or side effects develop. Improvement should be seen by the tenth dose. It usually eliminates the pain of an acute attack within 48 hours. The intravenous route has some serious side effects, however, and poses an increased risk for injury to the kidney, liver, central nervous system, and bone marrow.

The antibiotic erythromycin, or H2 blockers such as famotidine (Pepcid AC), cimetidine (Tagamet), or ranitidine (Zantac) may intensify the gastrointestinal side effects of colchicine.

Warning Note: Overdose of colchicine can be dangerous, and there have even been reports of death. The drug may also suppress blood cell production and cause nerve and muscular injury in certain people, sometimes even in those not taking high doses.

Q.40 Auranofin is used in

a) Rheumatoid Artharitis        b) Gout                        c) Hyperglycemia        d) Epilepsy

Ans 40. A Auranofin is a gold complex classified by the World Health Organization as an antirheumatic agent. It has the brand name Ridaura.

Auranofin is used to treat rheumatoid arthritis. It improves arthritis symptoms including painful or tender and swollen joints and morning stiffness.

Research

HIV infection

Auranofin is under investigation as means of reducing the viral reservoir of HIV that lies latent in the body's T-cells despite treatment with antiretroviral therapy. 

Amebiasis

Auranofin has been identified in a high-throughput drug screen as 10 times more potent than metronidazole on Entamoeba histolytica, the protozoan agent of human amebiasis. Assays of thioredoxin reductase and transcriptional profiling suggest that the effect of auranofin on the enzyme enhances the sensitivity of the trophozoites to reactive oxygen-mediated killing in mouse and hamster models; the results are markedly reductions of the number of parasites, the inflammatory reaction to the infestation and the damage to the liver.