the Body
Think of the body as divided into seven systems:
(click on the underlined links to learn more)
- [ bones ]
- [ brain and nerves ]
- [ muscles ]
- [ respiration ]
- [ circulation ]
- [ digestion ]
- [ glands ]
All are connected and interdependent, though each has a special network of its own.
Some glands, such as those of the skin and digestive tract, produce secretions which have an effect only where they are released; these are called exocrine glands. In contrast, the endocrine glands manufacture substances called hormones which pass directly into the blood stream and affect areas far removed from their place of origin. The secretions are fairly simple compounds many of which are now synthesised. They are effective in very small amounts and are regulators of body processes controlling growth, development, size weight, sexual activity, reproduction and temperament.
THE PITUITARY: Situated at the base of the brain, it is the master gland. It influences the rest of the endocrine system as well as performing specific functions such as regulating growth, controlling physical and mental development, acting on the sex organs, affecting menstruation, blood pressure and sight.
THE THYROID: Found in the neck, it organises the body's supply of oxygen. It also secretes an iodine-rich hormone, thyroxin, which works together with one from the pituitary. If the thyroid gland is defective (Often due to lack of iodine) metabolism slows down often resulting in overweight and lethargy; it can lead to goiter. Excess secretion causes nervousness, irritability and protruding eyeballs.
THE PARATHYROIDS: Either side of the thyroid, they control levels of calcium and phosphorus.
THE ADRENALS: These affect the nervous system, the emotions and influence the sex glands. They are found above the kidneys. Adrenaline is one hormonal secretion; stimulates the heart, quickens the pulse and causes a rise in blood sugar. It is released through fear and can cause anger. Cortisone is the other hormone.
THE PANCREAS: Part of the pancreas is used for digestion, the other part is a gland called the Island of Langerhans. This produces the hormone insulin which regulates the sugar level in the blood and the conversion of sugar into energy and heat. Imbalances cause diabetes or hypoglycaemia.
THE GONADS: The sex glands found in the ovaries; they produce oestrogen and progesterone which together regulate the reproductive cycle. A small quantity of male hormones are also produced; if excessive, male characteristics result.
[ the Body ]
Think of the body as divided into seven systems:
(click on the underlined links to learn more)
- [ bones ]
- [ brain and nerves ]
- [ muscles ]
- [ respiration ]
- [ circulation ]
- [ digestion ]
- [ glands ]
All are connected and interdependent, though each has a special network of its own.
Return to [ the Body ] Index page!