This set of Molecular Endocrinology Multiple Choice Questions & Answers (MCQs) focuses on “Posterior Pituitary”.
1. What is the name of the condition where there is Congenital absence of the pituitary gland?
a) Aplasia
b) Dysplasia
c) Anaplasia
d) Pituplasia
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Explanation: Congenital absence of the pituitary gland is known as aplasia. This condition called aplasia, partial hypoplasia, or ectopic tissue rudiments are rarely encountered. Endocrinopathies are behind the anterior pituitary aplasia or dysplasia and also with malformations of the eyes, brain, or somatic anomalies.
2. Pituitary development follows midline cell migration from which among the following tissues?
a) Somatotroph cells
b) Rathke’s pouch
c) Leydig cells
d) Lactotrophs
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Explanation: After pituitary development, there is midline cell migration from Rathke’s pouch. And damaged midline abnormalities lead to systemic pituitary anomalies, including failed forebrain cleavage and anterior commissure and corpus callosum defects.
3. Which is one of the earliest transcriptional markers of the primitive pituitary?
a) Lhx3
b) Lhx4
c) HESX1 (Rpx)
d) Ptx2
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Explanation: HESX1 (Rpx) is one of the earliest primitive pituitary transcriptional markers with an expression limited to Rathke’s pouch. In the mature anterior pituitary, leading to PROP1 activation, HESX1 expression decreases and is removed coincidentally with the appearance of specific types of pituitary cells.
4. Mutations in human PROP1 are associated with deficiencies in lineages dependent on POU1F1.
a) True
b) False
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Explanation: For POU1F1 activation, gene expression of PROP1 (Online Mendelian Inheritance in Man [OMIM]601538) is required. Hence, deficiencies in POU1F1-dependent lineages are influenced by human PROP1 mutations.
5. There is a hypogonadal phenotype in patients harboring PROP1 mutations.
a) True
b) False
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Explanation: In patients with combined pituitary hormone deficiency, the frequency of PROP1 gene mutations is high, with 30 percent to 50 percent of the subjects affected. And it is true that a hypogonadal phenotype is present in patients who possess PROP1 mutations.
6. Missense and deletion mutations of which of the following genes are associated with panhypopituitarism?
a) LHX4
b) LHX3
c) TPIT
d) HESX1
View Answer
Explanation: Except for an intact ACTH reserve, missense and deletion mutations of LHX3 are associated with panhypopituitarism. Due to a rigid cervical spine, these patients often exhibit defective neck rotation capacity. Pituitary Hormone Dysfunction, and Hypothyroidism due to deficient transcription factors involved in pituitary development or function are diseases associated with LHX3.
7. Ptx2 Rieger’s syndrome is associated with which of the following genes?
a) PITX2
b) Lhx4
c) TPIT
d) HESX1
View Answer
Explanation: GHD and haploinsufficiency of the RIEG (PITX2) homeobox gene are associated with Ptx2 Rieger’s syndrome. Basically, this condition is the maldevelopment of the anterior eye, teeth, and umbilical cord.
8. TPIT mutations result in which among the following diseases?
a) Panhypopituitarism
b) Septo-optic dysplasia
c) Rieger’s syndrome
d) Hypocortisolism
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Explanation: TPIT mutations result in isolated ACTH deficiency and hypocortisolism at an early-onset stage. Associated phenotypes include those of obesity, red hair pigmentation and other associated pituitary deficiencies.
9. Which among the following is an autosomal recessive disorder characterized by hypogonadotropic hypogonadism and other such disorders?
a) Lawrence-Moon-Biedl Syndrome
b) Rieger’s syndrome
c) Panhypopituitarism
d) Hypocortisolism
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Explanation: Lawrence-Moon-Biedl syndrome is an autosomal recessive condition characterized by mental retardation, hypogonadotropic hypogonadism, Obesity, retinitis pigmentosa, brachydactyly, or syndactyly, and hexadactyly. Most patients are blind in this disease by the age of 30 years.
10. Patients with which of the following diseases have marked hyperphagia and obesity with retarded mental development and associated disorders?
a) Lawrence-Moon-Biedl Syndrome
b) Prader-Willi Syndrome
c) Kallmann’s Syndrome
d) Rieger’s syndrome
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Explanation: Hyperphagia and obesity with retarded mental growth, muscle hypotonia, and diabetes mellitus have been reported in patients with Prader-Willi syndrome. Micrognathia, missing auricular cartilage, and acromicria are associated disorders.
11. Which disease consists of defective GnRH synthesis with olfactory nerve agenesis or hypoplasia and variable anosmia?
a) Lawrence-Moon-Biedl Syndrome
b) Prader-Willi Syndrome
c) Kallmann’s Syndrome
d) Rieger’s syndrome
View Answer
Explanation: Kallmann’s syndrome consists of incomplete synthesis of GnRH with hypoplasia or olfactory nerve agenesis and variable anosmia. Optic atrophy, color blindness, cranial nerve VIII deafness, cleft palate, renal agenesis, cryptorchidism, and movement disorders are associated developmental disorders.
12. Which protein mediates hypothalamic migration of GnRH cells from the primitive olfactory placode?
a) KAL protein
b) Ascites protein
c) CLB protein
d) IFG protein
View Answer
Explanation: A defective KAL gene located on chromosome Xp22.3 has been ascribed to Kallmann’s Syndrome. The KAL protein mediates hypothalamic migration of the primitive olfactory placode of GnRH cells, and its absence contributes to inaccurate synthesis and anosmia of GnRH.
13. Which among the following hormones is low or absent in patients with Kallmann’s syndrome?
a) Sex steroids
b) Insulin
c) Adrenal hormones
d) Peptide hormones
View Answer
Explanation: Patients with Kallmann’s syndrome are exposed from birth to sex steroids that are poor or absent. Consequently, females have primary amenorrhea and are usually tall. Kallmann syndrome is a condition characterized by an impaired sense of smell and delayed or absent puberty.
14. Which among the following drugs can inhibit gonadotropin action?
a) Estrogen
b) Progesterone
c) Allopurinol
d) Zyloprim
View Answer
Explanation: Gonadotropin activity is blocked by medications such as estrogens that suppress FSH and LH, and GnRH analogues used for prostate cancer treatment. Other vascular injuries, such as aneurysms, strokes, cavernous sinus thrombosis, and arteritis, can cause pituitary hormone insufficiency in addition to pituitary apoplexy.
15. Which among the following disease is caused by arachnoid herniation into the sellar space?
a) Empty Sella Syndrome
b) Sellar Pore Syndrome
c) Lesh Nyhan’s Syndrome
d) Prader-Willi Syndrome
View Answer
Explanation: Sellar diaphragm damage can lead to arachnoid herniation in the sellar space. As a result of primary congenital weakness of the diaphragm, patients in which no secondary cause is apparent, can develop an empty sella.
Sanfoundry Global Education & Learning Series – Molecular Endocrinology.
To practice all areas of Molecular Endocrinology, here is complete set of 1000+ Multiple Choice Questions and Answers.
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