Fundamentals of Nursing Q 472

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Hormones secreted by Islets of Langerhans

  

     A. Progesterone

     B. Testosterone

     C. Insulin

     D. Hemoglobin

    

    

Correct Answer: C. Insulin

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The Islets of Langerhans are the regions of the pancreas that contain its endocrine cells. Insulin is a peptide hormone secreted in the body by beta cells of islets of Langerhans of the pancreas and regulates blood glucose levels. Medical treatment with insulin is indicated when there is inadequate production or increased demands of insulin in the body.

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Option A: Progesterone (Choice A) is produced by the ovaries. Progesterone is an endogenous steroid hormone that is commonly produced by the adrenal cortex as well as the gonads, which consist of the ovaries and the testes. Progesterone is also secreted by the ovarian corpus luteum during the first ten weeks of pregnancy, followed by the placenta in the later phase of pregnancy.

Option B: Testosterone (Choice B) is secreted by the testicles of males and ovaries of females. Testosterone is the primary male hormone responsible for regulating sex differentiation, producing male sex characteristics, spermatogenesis and fertility. Testosterone is responsible for the development of primary sexual development, which includes testicular descent, spermatogenesis, enlargement of the penis and testes, and increasing libido.

Option D: Hemoglobin (Choice D) is a protein molecule in the red blood cells that carries oxygen from the lungs to the body’s tissues and returns carbon dioxide. Hemoglobin is an oxygen-binding protein found in erythrocytes which transports oxygen from the lungs to tissues. Each hemoglobin molecule is a tetramer made of four polypeptide globin chains. Each globin subunit contains a heme moiety formed of an organic protoporphyrin ring and a central iron ion in the ferrous state (Fe2+). The iron molecule in each heme moiety can bind and unbind oxygen, allowing for oxygen transport in the body.

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