منتدي نجم السودان
د.نجم الدين علي ياسين
يتمني لكم اقامه طيبه داخل صفحات المنتدي
ارجو التسجيل معنا حتي تتمكن من الاستمتاع بكل المزايا
منتدي نجم السودان

Important MCQ colloction for part-1 MRCOG(2) 13458470.b7d6c5

Join the forum, it's quick and easy

منتدي نجم السودان
د.نجم الدين علي ياسين
يتمني لكم اقامه طيبه داخل صفحات المنتدي
ارجو التسجيل معنا حتي تتمكن من الاستمتاع بكل المزايا
منتدي نجم السودان

Important MCQ colloction for part-1 MRCOG(2) 13458470.b7d6c5
منتدي نجم السودان
Would you like to react to this message? Create an account in a few clicks or log in to continue.

Important MCQ colloction for part-1 MRCOG(2)

Go down

Important MCQ colloction for part-1 MRCOG(2) Empty Important MCQ colloction for part-1 MRCOG(2)

Post by drsaima2000 Sun Jul 17, 2011 12:01 am

31- Isolated diathermy machines

A- Are earth referenced generators .................................................F

B- Operated in a frequency range of 400-600 kHz .............................F

C- Isolated machines are inherently safer ........................................F

D- Diathermy can only pass back to the generator via the patient plate.....T

E- Produce unavoidable large earth leakage currents.........................F


Modern diathermy machines are isolated (unearthed) generators as opposed to the old earth referenced generators. The old earth referenced generators tend to produce higher frequency current over a wider range than the narrow range of the isolated generators. Current will only pass back to the generator with no pathway back to earth i.e. a small area of skin touching a metal contact (eg drip stand) will not result in a burn. If the plate is omitted current will not flow. The sophisticated electronics in the isolated generator ensures a considerable reduction in earth leakage currents compared to the earth referenced generators.

32- Non-disjunction of chromosomes during meiosis is a cause of:[/u

A- Edward's syndrome ....................................................................T

B- Turner's syndrome .....................................................................F

C- Cri du chat syndrome ................................................................F

D- Patau's syndrome ......................................................................T

E- Laurence-Moon-Biedl syndrome ....................................................F

Non-dysjunction (the failure of replicated chromosomes to segregate during Anaphase II) during meiosis is responsible most typically for Down's syndrome (trisomy C21), Patau's syndrome (trisomy C13), Turner's syndrome (XO), Klinefelter's (XXY) syndrome and Edwards syndrome (Trisomy C18). Cri du Chat is due to a deletion of a portion of C5.

33- Campylobacter jejuni:

A- attack rates are highest in the elderly ..........................................F

B- infections are treated with ciprofloxacin ........................................T

C- is a recognised pathogen in domestic animals ................................T

D- is readily isolated in stool culture .................................................F

E- causes colitis ..............................................................................T


a-Young adults and children.
b-Cipro and Erythromycin, but most are self-limiting.
c-Transmitted to humans by milk or water infected by wild and domestic animals and poultry.
d-Requires special conditions: 42°C, micro-aerobic atmosphere on blood agar with antimicrobials added.
e-Proctocolitis and enterocolitis may be due to sexually transmitted agents such as CampylobacterEntamoeba Lymphogranuloma venereumand may be clinically indistinguishable from non-infective causes.

34- Mast cells:

A- Contain heparin .......................................................................T

B- Degranulation releases lytic enzymes and inflammatory mediators from storage granules ......F

C- Are lipophilic cells involved in inflammatory and immune responses ...F

D- Cross-linkage of surface IgA molecules by antigen may cause an anaphylactic reaction.......F

E- An excess of circulating mast cells causes mastocytosis ...................T


Mast cells are basophilic cells (not lipophilic) in the connective and subcutaneous tissues, which are involved in inflammatory and immune responses. They contain storage granules that contain lytic enzymes (e.g. tryptase) and inflammatory mediators, e.g. histamine, heparin, 5-HT, leukotrienes, platelet aggregating factor, leucocyte chemotactic factor and hyaluronidase. Release of these mediators occurs during mast cell degranulation, which can be triggered by: tissue injury; drugs; complement activation; and foreign antigenic material. An anaphylactic reaction occurs when a previously sensitised individual is re-exposed to the antigen. It is an IgE mediated immune response (not IgA). Mastocytosis occurs when excess mast cells are present in the circulation or as tissue infiltrates.

35- The following is true of diathermy safety features :

A- The person who applies the diathermy plate is responsible for its correct application......F

B- Only isolated diathermy machines alarm when switched on if the plate is not connected to the machine.........F

C- The patient plate is applied to ensure the current is moving away from the electrocardiogram electrodes.......T

D- The area under the plate should have a good blood supply.............T

E- Always shave the skin in contact with the diathermy plate...............T

The surgeon using the diathermy has overall responsibility for it and should check the alarm, wiring and plate before use. Isolated and earth referenced monopolar diathermy machines will alarm when switched on if the plate is not connected to the machine, but only a few will alarm if the plate is not attached to the patient. The plate should be applied close to the operation site with the broad side placed perpendicular to a line drawn from the operation site to the plate. A good supply is necessary to dissipate any heat generated. The skin should be shaven in all patients to ensure good contact between the skin and the plate.

36- Which of the following statements regarding meiosis is/are true/false ?

A- In meiosis II, whole chromosomes separate..................................F

B- In spermatogenesis, meiosis begins at puberty..............................T

C- Exchange of paternal and maternal DNA takes place in meiosis II....F

D- Anaphase lag leads to numerical chromosome aberrations..............T

E- Pairing of X and Y chromosomes in spermatogenesis is end to end....T

In meiosis there is a separation of the chromosomes and halving of karyotype to form germ cells. Meiosis (I and II) comprises two successive nuclear divisions with only one round of DNA replication.

37- The urinary system

A- develops from intermediate mesoderm ........................................T

B- During intra uterine life 3 overlapping kidney systems are formed ...T

C- The mesonephros develops as the metanephros regresses ..............F

D- Bowman's capsule develops in the metanephros ............................T

E- The glomerulus forms part of the mesonephros ...............................F

The urinary system develops from the intermediate mesoderm. During development of the fetus there are 3 overlapping kidney systems - the pro, meso, and metanephric systems. The metanephros forms the permanent kidney. Bowman's capsule and the glomerulus develop as part of the metanephros.

38- The ureter:

A- Passes into the pelvis over the bifurcation of the internal iliac artery...F

B- Is seen lying on the tips of the transverse processes of the lumbar ...T

C- Has the genitofemoral nerve lying anterior to it ...............................F

D- Is surrounded by Waldeyer’s sheath as it passes through the bladder wall .....T

E- Lies anterior to the renal artery at the hilum of the kidney ...............F

The ureter passes caudally lying on the psoas muscle and crosses into the pelvis over the bifurcation of the common iliac artery. It is seen lying on the tips of the transverse processes of the lumbar vertebrae on an intravenous urogram. the genitofemoral nerve lies on psoas hence lies posterior to the ureter. Waldeyer's sheath is an investment of muscle surrounding the ureteral opening in the bladder wall. The ureter lies posterior to the renal artery at the hilum of the kidney

39- The herpes group of viruses include:

A- Varicella-zoster virus ....................................................................T

B- Papilloma virus ............................................................................F

C- Rabies virus ................................................................................F

D- Epstein-Barr virus ........................................................................T

E- Cytomegalovirus ..........................................................................T

The Herpesviridae family of viruses are dsDNA viruses that include herpes simplex, varicella zoster, CMV and EBV. The papilloma virus, a small dsDNA virus, is a member of the Papovavius family. Rabies, a ssRNA virus, is a member of the Rhabdovirus family.

39.The structures at risk of damage while cannulating the subclavian vein include:

A- phrenic nerve ..........................................................................T

B- subclavian artery .....................................................................T

C- ansa cervicalis .........................................................................F

D- anterior ramus of first thoracic nerve ........................................T

E- pleura .....................................................................................T

The subclavian artery lies inferior to the suclavian vein and may be inadvertently cannulated in an attempt to cannulate the suclavian vein. This may be of serious consequence as it is not possible to put pressure on the subclavian artery to arrest bleeding given its anatomical position. The apical pleura is inferior and caudal to the subclavian vein and pleural puncture, with, or without, pneumothorax are recognised consequences of subclavian vein cannulation.

40.In acute allergic reaction

A- there is an increase in bradykinins ...............................................T

B- T-helper cells are involved ..........................................................T

C- there is an increase in the products of the 5-lipoxygenase pathway ....T

D- the gene for allergy is located on chromosome 12 .........................F

E- may be triggered by acute complement activation ..........................T

c) Leukotrines
d) The gene is located on chromosome 6
e) Anaphylatoxins

41.The amnion arises from epithelial cells between the trophoblast

A- and ectodermal disc ..................................................................T

B- The amnion has 5 layers ...........................................................T

C- the chorion has 4 layers ..........................................................T

D- the main layer of the chorion is the cellular layer .......................F

E- the chorion is surrounded by the blastocyst ................................F


The amnion is a layer of epithelial cells between the chorion and the cell mass. It has 5 layers compared to the 4 layer chorion. The chorion surrounds the blastocyst.
42.Concerning grief reactions

A- angry outbursts are a typical feature of the natural grieving process ......T

B- hallucinations of the deceased can be a feature of the normal grief reaction ......T

C- grief reactions may occur many years after the death of the person ....T

D- suicidal ideations are a common feature of a grief reaction .............F

E- Antidepressants is the most appropriate initial therapy ...................F

Grief reactions are typically mapped along the lines of anger denial and guilt. Delayed grief is said to occur if it commences two weeks after bereavement. Grief reactions often occur on anniverseries such as weddings, births etc. The most appropriate treatment is conselling and antidepressants should not be routinely used. Suicidal ideations are also abnormal.


43.Which of the following are tumour suppressor genes?

A- p53 ...........................................................................................T

B- BRAC1 ......................................................................................T

C- APC .........................................................................................T

D- bcl-2 .......................................................................................F

E- c-myc .......................................................................................F

Mutations in Tumour suppressor genes have been implicated in malignancy as down regulation of these genes can result in the unrestricted growth of cells and hence predispose to malignancy. These genes include VHL (von Hippel Lindau), p53, Rb1(Retinblastoma), BRAC and APC (adenomatous polyposis coli) genes. Oncogenes, on the other hand are associated with the promotion of cell division and include myc, erb, ras and ret.

44.Trinucleotide repeat sequences are seen in

A- cystic fibrosis .............................................................................F

B- Duchenne muscular dystrophy ....................................................F

C- myotonic dystrophy ...................................................................T

D- fragile X syndrome .....................................................................T

E- Leber's optic atrophy ..................................................................F

also Huntington's chorea
In genetics, anticipation is a phenomenon whereby the symptoms of a genetic disorder become apparent at an earlier age as it is passed on to the next generation. In most cases, an increase of severity of symptoms is also noted. It is common in trinucleotide repeat disorders like Huntington's disease, myotonic dystrophy and fragile X syndrome, where a dynamic mutation in DNA occurs. All of these diseases have neurological symptoms.

45.Which of the following drugs are teratogenic

A- Warfarin ..................................................................................T

B- Oral contraceptive ...................................................................F

C- Metformin ..............................................................................F

D- Simvastatin ...........................................................................T

E- Ranitidine ...............................................................................F


There is no evidence that ranitidine, metformin or the OCP is teratogenic although it was once believed that aspirin and the OCP were, studies indicate otherwise. Similarly, metformin is often used in PCOs to induce fertility through reduction in insulin resistance. Warfarin is associated with CNS and skeletal abnormalities if foetal exposure occurs in the first trimester, plus foetal haemorrhage is more likely. Statins also are associated with teratogenicity.

46.In haemophilia A

A- dental extraction bleeding can be controlled with DDAVP if factor VIII concentration is 2-5% of normal ..............F

B- sons of an affected man will be normal ........................................T

C- Only about 90% have bleeding before one year of age ...................T

D- hepatitis B virus is the most common cause of deranged LFTs .........F

E- there is a normal amount of factor VIII-related antigen ...................T

Only in mild cases (5-20% activity)is bleeding controlled by DDAVP.
Haemophilia A is X-linked recessive. Sons of affected males will inherit a normal Y chromosome, and will be unaffected.
Hepatitis C or E would be commoner as a cause of abrnomal LFTs in these patients, as hepatitis B is more easily screened for.
Factor VIII related antigen is reduced in von Willibrand's disease.
90% present with bleeding by their first birthday. Only 30% present with bleeding after circumcision.

47.Which of the following are Tocolytic:

A- Salbutamol ...............................................................................T

B- Suxamethonium .......................................................................F

C- Propofol ..................................................................................F

D- Progesterone ...........................................................................T

E- GTN .........................................................................................T

Tocolytic drugs, inhibitors of uterine contraction, include GTN, alcohol, magnesium sulphate, ritodrine, salbutamol, nifedipine and NSAIDs. Progesterone in high concentrations also has some tocolytic activity and promotes the relaxant effects of more conventional tocolytics.

48.Metronidazole:

A- Inhibits dihydrofolate reductase. .................................................F

B- Has 80% bioavailability if given rectally. ......................................T

C- Has harmful effects with alcohol. .................................................T

D- Discolours the urine....................................................................T

E- Causes peripheral neuropathy......................................................T

Reduced to active derivative which binds to DNA and inhibits acid synthesis. Disulfiram reaction with alcohol. Some types of Warfarin. Metallic taste, hypotension, peripheral neuropathy and also causes a darkening of the urine.

49.Polymerase chain reaction:

A- takes several days to complete ....................................................F

B- DNA or RNA can be used as the template ....................................T

C- helps in diagnosis of infection ......................................................T

D- in diagnostic PCR the exact sequence at both ends of the target region must be known .......T

E- Polymorphisms in the viral genome may result in amplification failure .....T


The polymerase chain reaction is a rapid technique which produces a result in only a few hours. It is therefore extremely useful for rapid diagnosis of conditions such as tuberculosis where traditional culture methods can take several weeks. DNA is the standard template but viral RNA sequence can also be amplified if the enzyme reverse transcriptase is used. Primers used in the reaction must be complementary to the nucleic acid sequence surrounding the region to be amplified, therefore these sequences must be known. In HIV and perhaps other viruses sequence polymorphism may prevent binding of primers and result in failure of amplification. Primers which were developed for amplification of the predominant clade B strain found in Europeans and Americans have proved unreliable for amplification of other HIV clades from Africa and Asia.

50.The following are true of genes

A- The rate of DNA replication is directly under the control of enhancer sequences.............F

B- Mitochondrial genes are inherited from the mother..........................T

C- Transcription factors are mainly made of RNA................................T

D- Introns are the portions of a gene which code for protein................T

E- Most of the human genome encodes polypeptide.............................F


A gene is a length of DNA that carries information to make a single peptide chain. However, it is estimated that only a few percent of DNA comprising the whole human genome consists of genes encoding protein. Introns are intervening sequences of unknown function in mammalian genes. Regulatory elements of gene transcription include promoters (regions of DNA to which RNA polymerase bind and initiate transcription), enhancer sequences (modify activity of genes on the same chromosome) and transacting proteins (modify genes on both pairs of homologous chromosomes). mRNA are transcripts of DNA, which are attached to transfer RNA and then translated in ribosomes to protein, which then undergo considerable post-translational changes. Mitochondrial inheritance is exclusively maternal, as none of the mitochondria from sperm survives fertilization.
51.The following mechanisms are involved in the mediation of insulin action:

A- adenylate cyclase activation ........................................................F

B- cell membrane receptor interaction ..............................................T

C- inhibition of hepatic glucose release .............................................T

D- receptor tyrosine kinase activity ..................................................T

E- hormone receptor DNA binding ....................................................F


Insulin acts through a disulfide-bonded heterotetrameric cell surface receptor comprised of an extracellular alpha subunit coupled via disulfide bonds to a transmembrane and intracellular beta subunit. Insulin inhibits gluconeogenesis and promotes glycogen synthesis. Signaling through the insulin receptor occurs through an intracellular tyrosine kinase domain and resultant phosphorylation of the receptor.

52.The seminal vesicles:

A- Contain spermatids ...................................................................F

B- Contain spermatids .................................................................F

C- Secrete acid phosphatase .........................................................F

D- Secrete fructose ......................................................................T

E- Secrete prostaglandins .............................................................T

Seminal vesicles secrete a significant proportion of the fluid that ultimately becomes semen. About 60% of the seminal fluid in humans originates from the seminal vesicles. The seminal vesicles do not contain sperm cells. Seminal vesicle secretions contain proteins, enzymes, fructose, phosphorylcholine and prostaglandins.



53.Regarding the human chromosomes:

A- There are 23 pairs of autosomal chromosomes...............................F

B- The Y chromosome is larger than the X chromosome......................F

C- Cells containing YO chromosome are not compatible with life...........T

D- Barr body is caused by the presence of an inactive X chromosome.....T

E- Barr body is only found in people who are phenotypically female........F

There are 22 pairs of autosomes, and one pair of sex chromosomes. The Y chromosome is smaller than the X chromosome, no YO individuals have been identified, not even aborted foetuses. It has been suggested that there is something fundamental on the X chromosome that is needed for life. The Barr body is visible during interphase and chromosomes are too tenuous to be stained and seen by light microscopy. However, a dense, stainable structure, called a Barr body (after its discoverer) is seen in the interphase nuclei of female mammals. The Barr body is one of the X chromosomes. Its compact appearance reflects its inactivity. People with XXY or XXXY karyotypes are males (because of their Y chromosome), and display the features of Klinefelter’s syndrome. The phenotypic effects of the extra X chromosomes are mild because, just as in females, the extra Xs are inactivated and converted into Barr bodies

54. Typical adverse effects of combined oral contraceptive preparations include:

A- Migraine ...................................................................................T

B- Hyperprolactinaemia .................................................................F

C- Depression ...............................................................................T

D- Breast tenderness ....................................................................T

E- Loss of libido ............................................................................F


Menstrual migraine: First migraines associated with a hormonal event: menarche, birth control pills, pregnancy, and/or postpartum Worse headaches occur near menstruation Birth controls often make headaches worse; discontinuation may bring some relief. Headache typically occurs the week off birth control pills, Absence of migraine noted in second & third trimesters of pregnancy. Presence of other premenstrual complaints: mood swings, depression, food cravings, fluid retention and breast pain. Side-effects include depression or irritability. The effect on libido is variable. In many women relief from fear of pregnancy removes a restraint on sexual activity and enjoyment; in a very few there will be a loss of libido. The other side effects of greatest concern with the combined OCP are vascular events including DVT and stroke (v rare).

55. The menopause

A- Implies cessation of menstrual flow for one year or more ................T

B- Is synonymous with the climacteric ..............................................F

C- Symptoms may occur long before menstruation ceases..................T

D- Occurs on average at age 45.5 years ..........................................F

E- Is associated with mennorhagia ..................................................F

The menopause is the cessation of normal menstruation. Conventionally a woman has to stop menstruating for 12 months before she is considered to be postmenopausal. Strictly speaking, menopause is defined as cessation of menses for a minimum of 6 months because of inadequate ovarian follicular development and waning oestrogen production. The climacteric is an extended period of gradually declining ovarian function often beginning years before and lasting years after menopause itself. The average age of menopause in the UK is 51 years, with a large majority of women experiencing menopause between the ages of 45 and 55. The cessation of periods, can occur suddenly or may be preceded by light and infrequent periods. The climacteric (rather than the menopause) although typically associated with light periods may be heralded by menorrhagia.

56. The benefits of adding androgen to menopausal hormone replacement therapy include which of the following:

A- Increase in high-density lipoprotein cholesterol levels......................F

B- Increase in libido.........................................................................T

C- Decrease in triglyceride levels......................................................T

D- Decrease in bone mineral density.................................................F

E- Decreased cardiovascular risk .....................................................F




Androgens are known to increase libido and may help to protect bone mass. However, lipid profiles change when androgens are added to HRT. The HDL fraction decreases with androgen therapy; however, triglyceride concentrations decrease significantly in patients given oestrogen-androgen combination therapy.

57. Growth Hormone:

A- secretion is inhibited by somatostatin analogues ............................T

B- is used in the treatment of proliferative retinopathy .......................F

C- therapy causes an elevation of IGF-1 concentrations .....................T

D- is approved by NICE for the treatment of adult hypopituitarism ......T

E- therapy is associated with an increased incidence of breast carcinoma .............F



GH therapy produces an elevation of IGF-1 and therapy is monitored through measuring these concentrations. GH therapy is approved for the treatment of adult hypopituitarism and there is no evidence to suggest that it causes an oncreased risk in any malignancy. Treatment is contra-indicated in any active malignancy and indeed proliferative retinopathy. GH secretion is suppressed by somatostatin analogues - eg octreotide, which are used therefore in acromegaly.

58. Proteolytic enzymes are released by the following organisms:

A- Neisseria meningitides ................................................................F

B- Salmonella typhi .........................................................................F

C- Streptococcus pyogenes .............................................................T

D- Mycobacterium tuberculosis ........................................................F

E- Clostridium perfringens (welchii) .................................................T



Virulence factors are important in the bacterial survival in vivo. In this sense bacterial extracellular proteolytic enzymes can be recognized as the legitimate target for this approach since they are involved either in direct or indirect destruction of an infected/colonized tissue and in dysregulation of many host defense pathways. The best example of the last is an effect of bacterial proteinases on fibrinolytic, kallikrein-kinin and complement cascades, as well as degradation of immunoglobulins, inactivation of endogenous proteinase inhibitors, and dysregulation of cytokine network system. Proteolytic enzymes are responsible for the virulence and activity of organisms such as Strep Pyogenes, Staphylococcus aureus, E coli and Clostridium welchii enabling the necrolytic effects on the skin in cellulitis and gangrene

59. The thyroid gland:

A- Is stimulated by posterior pituitary hormones ...............................F

B- Functions from the 12th week of fetal development ......................T

C- Actively traps inorganic iodine from plasma ..................................T

D- Stores colloid outside epithelial cells .............................................T

E- Enlarges during normal pregnancy ................................................T



Thyroid hormone production is stimulated by the anterior pituitary hormone TSH and secretion begins from approximately the 12th week of gestation. T3 and T4 are manufactured within the thyroid cells through iodination of tyrosine. The synthesized T3 and T4\ are then stored within the colloid at the centre of the thyroid follicles. The thyroid like most other endocrine organs moderately enlarges during pregnancy.

60. The human testis secretes:

A- Androstenedione .......................................................................T

B- Luteinising hormone ...................................................................F

C- Oestradiol ..................................................................................T

D- Inhibin .......................................................................................T

E- Fructose .....................................................................................F



The testis is responsible for secreting testosterone, androstenedione, Oestradiol, inhibin as well as a small amount of progesterone. The anterior pituitary produces LH and FSH. Fructose and prostaglandins that nourish the spermatozoa are secreted by the seminal vesicles.

61. Staphylococcus epidermidis:

A- is coagulase positive .................................................................F

B- on microscopy are Gram positive cocci in chains .......................F

C- are usually sensitive to penicillin ...................................................F

D- grown in blood cultures are due to contamination and should be ignored ...........F

E- are destroyed by povodine iodine ...................................................T



Staph. epidermidis is part of the normal skin flora. As for Staph. aureus, Gram positive cocci in bunches are seen on microscopy.
It is usually insensitive to penicillin.Although it is often a contaminant in blood cultures, it is associated with line infections. Central venous catheters are an especially likely site of infection even in the absence of overt exit site sepsis. They should not be ignored but interpreted in the clinical context, and usually the blood cultures should be repeated. In patients with central lines, blood cultures should be taken both peripherally and from the central line as semi-quantitative microbiological techniques are available that may point to the central line as the principle site of infection.

62. The following hepatitis viruses are RNA viruses:

A- HAV ...........................................................................................T

B- HBV ...........................................................................................F

C- HCV ..........................................................................................T

D- HDV ..........................................................................................T

E- EBV ..........................................................................................F



Hepatitis A is an RNA virus spread via the faecal-oral route. Whilst both HBV and HCV are transmitted through blood and blood products, HBV is a DNA virus and Hepatitis C is an RNA flavivirus. Hepatitis D is an incomplete RNA virus, existing only with H epatitis B, spread is with co-infection or super-infection with Hepatitis B. Epstein Barr Virus is a DNA virus, very similar to the other herpes viruses. It is shed in pharyngeal secretions and transmission occurs via close oral contact.

63. Regarding Immunoglobulin:

A- Immunoglobulins are secreted from T-lymphocytes. ......................F

B- An immunoglobulin G (IgG) comprises 2 antigen-binding sites and a site for the binding of complement.........T

C- The molecular structure of IgG is a Y shape ...................................T

D- IgG constitute approximately 25% of all immunoglobulis in a healthy individual........F

E- IgMs can cross the placenta to the foetus........................................F


Immunoglobulins (antibodies) are secreted from B-lymphocytes (plasma cells) in response to a specific antigen. Both antigen-binding sites are identical and consist of a long and heavy chain. IgGs constitute approximately 75% of all immunoglobulis in a healthy individual. Only IgGs can cross the placenta. This is important as they provide immune protection for the newborn in the first few months of life.

64. Disinfectant solutions may become contaminated with:

A- Enterobacter species ...................................................................T

B- Streptococcus species .................................................................F

C- Escherichia coli .........................................................................F

D- Pseudomonas aeruginosa (pyocyanea) .......................................T

E- Staphylococcus pyogenes ...........................................................F


Disinfectant solutions have variable bactericidal and fungicidal properties but are usually but there are reports of contamination with Pseudomonas spp, Enterobacter, Serratia, actinomyces and Fungi.

65. Use of the combined oral contraceptive pill is associasted with an increased risk of:

A- Ovarian carcinoma .....................................................................F

B- Breast Carcinoma ......................................................................T

C- Endometrial carcinoma ..............................................................F

D- Hepatic carcinoma ......................................................................T

E- Cervical carcinoma ....................................................................T




The risks of some cancers are associated with use of the OCP. In particular, it appears that breast cancer risk is increased and, use of the OCP for more than 5 years is associated with increased risk of cervical carcinoma. Hepatoma risk may also be increased with use of the OCP. Use may be protective for ovarian carcinoma.

66.Unopposed oestrogen therapy for the postmenopausal female

A- Improves the urethral syndrome ...................................................T

B- Decreases urinary calcium excretion .............................................T

C- Reduces the incidence of myocardial infarction ..............................F

D- Causes an increased incidence of endometrial carcinoma ..............T

E- Cause hypertension ....................................................................F

Low levels of natural oestrogen around and after menopause diminish the body's ability to absorb calcium and to metabolize vitamin D. Low oestrogen levels lead to a thinning of trabecular bone and eventually osteoporosis. This leads to an increased risk of fractures of the hip and wrist and compression fractures of the vertebrae resulting in a dowager hump. Rather than the original belief that postmenopausal HRT reduces CV risk, studies like WHI and HERS show an increased CV mortality and morbidity associated with HRT. Neoplasia of the endometrium may follow unopposed oestrogen; the risk increases with the duration of use:x 3-6 after five years of use. x 10 after ten years. That is why unopposed oestrogens are no longer used in subjects with an intact uterus.

67. The following are precursors of oestradiol

A- Cholesterol ..................................................................................T

B- Stilboestrol ..................................................................................F

C- Arachidonic acid ...........................................................................F

D- Dehydroepiandrosterone .............................................................T

E- Testosterone ................................................................................T

The pathways whereby oestrogens are synthesized in the ovary
Cholesterol to Pregnenolone then via D4 pathway: Progesterone to 17-hydroxyprogesterone (17-OHP) to Androstenedione (D4) « Testosterone to Oestradiol-17b (E2) or via D5 pathway: 17-hydroxypregnenolone to Dehydroepiandrosterone (DHA) to Oestrone (E1) «

68. Prostaglandins are

A- Synthesized from cholesterol ......................................................F

B- Are small polypeptides ...............................................................F

C- Secreted by the pituitary gland ...................................................F

D- Secreted by the prostate gland ...................................................T

E- Associated with gastrointestinal side effects ..................................T


Prostaglandins are long-chain hydroxy fatty acids derived from arachidonic acid, which is released from cell membrane phospholipids and catalysed by the enzymes cyclo-oxygenase and endoperoxidase. Prostaglandins are produced locally. The original source was the prostate. GI side effects include diarrhoea and abdominal pains.

69. The Barr body

A- arises from the Y chromosome .................................................F

B- is present in subjects with Turner's syndrome ...........................F

C- is present in 20% of cells in the male ........................................F

D- appears as a dense rod close to the cell wall .............................F

E- is present in males with Klinefelter's syndrome .............................T




The chromatin nodule is the second (inactive) X chromosome. Normal women are thromatin positive. Normal men are chromatin negative. In polymorphonuclear leucocytes, a tiny nodule of chromatin (the Barr body, or nuclear drumstick) can be seen near the nuclear membrane of many cells in normal females, but not in normal males. Turner's XO does not have a Barr body. In Klinefelter's syndrome the sex chromosomal structure is XXY, and in them a chromatin nodule is seen.

70. Androgens:

A- Exert a feedback inhibitory effect on FSH production .....................T

B- Produce a release of LH from the ovary ........................................F

C- Are produced in the ovary ..........................................................T

D- Are secreted by the female adrenal cortex ...................................T

E- Are formed in the Leydig cells of the testis ....................................F



Testosterone, like oestradiol, feeds back at the hypothalamus / pituitary to inhibit GnRH secretion and switch off both LH and FSH secretion. In the female, testosterone is synthesied in small amounts, probably in the adrenals, but a weak androgen, androstenedione is formed as a step in the metabolism of progesterone. LH stimulates testosterone production from Leydig cells of the testis.

71. IgA:

A- Is involved in mucosal immunity....................................................T

B- Has 4 distinct sub-groups...............................................................F

C- Activates complement via the classical pathway...............................F

D- Is manufactured in lymph nodes....................................................F

E- Crosses the placenta. ...................................................................F


IgA is the major antibody produced by plasma cells near mucosal surfaces, and is found in tears, sweat, lung, gut, urine. IgA avoids digestion by the presence of the secretory piece which is added as it is secreted onto the mucosa. It is an important defence against surface binding of micro-organisms. There are 2 sub-types, IgA1 and IgA2. Only IgG is transferred across the placenta. Complement proteins circulate, therefore, they rarely come into contact with IgA.

72. Circulating anticoagulants have been described in

A- Systemic Lupus Erythematosis ......................................................T

B- post-partum ................................................................................T

C- homocystinuria ..........................................................................F

D- haemophilia ...............................................................................T

E- the elderly ..................................................................................T




Circulating anticoagulant, usually IgG, interfere with coagulation reactions. The main laboratory feature are prolonged PT and PTT which persists if normal plasma is added.
a-These are non-specific inhibitors which prolong haemostasis by binding to phospholipids. Anti-factor VIII antibodies may also be seen.
b,d and e-Anti-factor VIII antibodies.
c-Thrombotic tendency.
d-haemophiliacs who have had plasma transfusions.

73. A karyotype

A- may be prepared from chorionic villi cells of the placenta................T

B- helps in the diagnosis of chromosome disorders.............................T

C- is made from cells arrested at telophase of mitosis.........................F

D- from a Patau syndrome patient shows an extra chromosome No. 18.....F

E- helps in the identification of the Philadelphia chromosome, in chronic myeloid leukaemia......T


Karyotype is the chromosomal composition of cells- normal karyotype is 46XX or XY. Patau syndrome is associated with trisomy of Chromosome 13.

74. Which of the following organelles have their own self replicating DNA?

A- lysosomes ...................................................................................F

B- Golgi body ..................................................................................F

C- mitochondria ..............................................................................T

D- nucleolus ....................................................................................F

E- rough ER ....................................................................................F



Mitochondria are well recognised to contain DNA and give rise to maternally inherited diseases such as the mitochondrial myopathies - red ragged fibres - DIDMOAD syndrome, Wolfram disease

74. Immunoglobulin G (IgG)

A- constitutes the natural haemagglutinins (anti-A and anti-B) ............F

B- is the predominant immunoglobulin in normal bronchial secretions ....F

C- freely crosses the placenta ..........................................................T

D- has a molecular weight of 350,000 daltons ...................................F

E- bears only 2 antigen-binding sites ................................................T

a) IgM,
b) IgA,
c) the only Ig to do so,
d) 150,000

75. Which of the following statements regarding DNA is/are true/false ?

A- Attached to the 2' position of the sugar ring is one of four bases.......F

B- The bases lie stacked on each other 3.4 Angstroms apart................T

C- During transcription each daughter DNA contains one newly synthesised strand.........F

D- The guanine - cytosine bonds are made of two hydrogen bonds. .......F

E- The DNA from a single cell is nearly 2 metres long..........................T





Individual nucleoside units (bases) are joined together in a nucleic acid in a linear manner, through phosphate groups attached to the 3' and 5' positions of the sugar (deoxyribose). Hence, the full repeating unit in a nucleic acid is a 3',5'-nucleotide.
Guanine - cytosine bonds consist of three hydrogen bonds.

drsaima2000
drsaima2000
جني
جني

عدد المساهمات : 10
نقاط : 26
السٌّمعَة : 5
تاريخ التسجيل : 2011-07-16

Back to top Go down

Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum