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gigantism
gigantism condition in which an animal or plant is far greater than normal in size. Plants are often deliberately bred to increase their size. However, among animals, gigantism is usually the result of hereditary and glandular disturbance. Among humans, gigantism is produced by an oversecretion of growth hormones by the acidophilic cells in the anterior lobe of the pituitary, causing excessive growth of all the tissues of the body. The metabolic rate is usually at least 20% above normal, which could be caused by an excess of the growth hormone alone, or oversecretion of the thyroid hormone in addition. Usually hyperglycemia (overactivity of the insulin-producing cells of the pancreas) is present. This condition eventually leads to degeneration of the islet cells, causing diabetes. Because of these metabolic abnormalities, the life expectancy of a giant is considerably less than normal. The treatment for gigantism is usually irradiation of the pituitary. The excessive height of the pituitary giant, which is defined at various levels above 7 ft (213 cm), is caused by excessive growth of the long bones. However, if the pituitary becomes overactive after growth is complete (marked by closure of the epiphyses of the long bones), the condition known as acromegaly results. Giants appear in the legends and folklore of many cultures. |
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"gigantism." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. "gigantism." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1E1-gigantis.html "gigantism." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-gigantis.html |
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gigantism
gi·gan·tism / jīˈgantizəm/ • n. chiefly Biol. unusual or abnormal largeness. ∎ Med. excessive growth due to hormonal imbalance. ∎ Bot. excessive size in plants due to polyploidy. |
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"gigantism." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. "gigantism." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1O999-gigantism.html "gigantism." The Oxford Pocket Dictionary of Current English. 2009. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-gigantism.html |
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gigantism
gigantism (jy-gan-tizm) n. abnormal growth causing excessive height, most commonly due to oversecretion during childhood of growth hormone (somatotrophin) by the pituitary gland.
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"gigantism." A Dictionary of Nursing. 2008. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. "gigantism." A Dictionary of Nursing. 2008. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1O62-gigantism.html "gigantism." A Dictionary of Nursing. 2008. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-gigantism.html |
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gigantism
gigantism See growth hormone.
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"gigantism." A Dictionary of Biology. 2004. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. "gigantism." A Dictionary of Biology. 2004. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1O6-gigantism.html "gigantism." A Dictionary of Biology. 2004. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-gigantism.html |
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