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Hormones: Properties, Types and Classification

Hormone word is derived from a Greek word hormaein, which means to execute or to arouse it was first used in reference to Secretin and Gastrin. The first hormone was discovered by English Physiologist William M. Bayliss and Ernest H. Starling in 1903. The term hormone was introduced by Starling in 1905.

Properties of Hormones (general characteristics of Hormones)

  1. They are secreted by a group of cells called endocrinal or glandular cells in the body and secretions enter in the blood. They can also be synthesized in cultures of endocrinal cells out side (in Vitro) the body

  2. Hormones are transported… (287 more words) …

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Hormones of Thymus

Origin; it is derived from the endoderm of the embryo

Location and structure; it is located in the upper part of thorax near the heart. It is a soft, pinkish, bilobed mass of lymphoid tissue. It is prominent at the time of birth but gradually atrophies in the adult.

Image of Thymus Glands

Image of Thymus Glands

showing the Thymus Glands in image

Hormone: it secrets a hormone thymosin.

Functions; its functions are not very clear

  • It stimulates the development of WBCs which are involved in the immunity.

  • It hastens attainment of sexual maturity.

  • Thymus involutes at puberty possibly… (40 more words) …

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