Quisitor - Take Quiz

1

Which one of the following statements regarding lactation is correct?

Prolactin concentrations become elevated prior to puberty.

During pregnancy progesterone and oestrogen block the action of prolactin on the breast.

In the non pregnant state mammary alveoli are usually secretory.

Oxytocin increases the sensitivity of alveolar cells to prolactin.

Lactational amenorrhoea is associated with improved fertility.

2

The hypothalamic hormone TRH acts on which one of the following?

The adrenal cortex to stimulate glucocorticoid synthesis and release.

The ovary to stimulate the release of oestrogen.

The thyroid follicular cells to stimulate synthesis of transthyretin.

The anterior pituitary thyrotrophs to evoke TSH secretion.

The adrenal medulla to evoke adrenaline secretion.

3

Which one of the following hormones is NOT controlled by a hypothalamic hormone released into the portal venous system between the hypothalamus and pituitary?

Oxytocin.

Follicle stimulating hormone.

Luteinizing hormone.

Thyroid stimulating hormone.

Growth hormone.

4

Growth hormone acts on which one of the following?

A cell surface G protein-coupled receptor to activate adenylate cyclase and increase cAMP levels.

A cytosolic receptor that migrates into the nucleus following hormone binding.

A cell surface receptor that has intrinsic guanylate cyclase activity and increases cGMP levels.

A cell surface receptor that couples to cytosolic tyrosine kinases.

A nuclear receptor that causes proliferation and enhanced cell growth.

5

Which one of the following statements is correct about peptide, steroid and thyroid hormone action?

Thyroid hormones interact with cell surface receptors.

Steroid hormones interact with nuclear receptors.

Peptide hormones interact with cytosolic receptors.

Receptor activation by steroid hormones results in transcription, translation and new protein synthesis.

Receptor activation by peptide hormones inhibits protein kinase C.

6

Which one of the following statements regarding metabolism of circulating hormones is correct?

Angiotensin II is converted to angiotensin I in plasma.

Testosterone is converted to dihydrotestosterone in target tissues.

Oestradiol is converted to testosterone in fat tissues.

25-hydroxy cholecalciferol is converted to cholecalciferol in the liver.

Cortisone is converted to cortisol in the kidney.

7

Which one of the following statements about thyroxine (T4) and tri-iodothyronine (T3) is correct?

T4 is available to cells by local conversion from T3.

T4 has a similar half-life to T3.

80% of T4 is produced by extrathyroidal conversion.

Conversion of T4 to T3 leads to increased biologic activity.

T3 has little, if any, intrinsic biological activity.

8

Which one of the following facts about dihydrotestosterone is correct?

It is produced from testosterone.

It is converted into testosterone.

It acts on the uterus.

It has no effect on the prostate.

Its synthesis is regulated by aromatase.

9

Which one of the following is NOT a site of testosterone production?

The ovary.

The fetal testis.

The adrenal medulla.

The ageing testis.

The neonate.

10

Which one of the following facts about cortisone is correct?

It is the main glucocorticoid.

It can be converted into cortisol.

It is synthesized in the adrenal medulla.

It is synthesized from testosterone.

It is a potent steroid hormone.

CSGD Quiz 4 2009

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