Endocrine System

This hormone, produced by the posterior lobe of the pituitary and secretion of which depends on the water content of the blood, encourages the reabsorption of water in the nephron of the kidney. It controls osmoregulation. A deficiency causes diabetes insipidus. It is also known as vasopressin. / ADH (antidiuretic hormone)
Ductless glands (endocrine), one found on top of both kidneys. They secrete adrenaline. / adrenal glands
Hormone produced by adrenal glands, the 'fight or flight' hormone. It stimulates the body in emergencies. Promotes respiration (with the release of energy) and stimulates the circulatory system. / adrenaline
The amount of carbohydrate, mainly glucose, in the blood plasma (normal amount 70 – 120mg per 100ml of blood), controlled by the hormone insulin. / blood sugar level
Not having a duct or tubule attached. Refers to endocrine glands where secretions are emptied directly into the blood or lymph systems. / ductless
Ductless gland. Secretions (hormones) delivered directly into bloodstream by the following glands: pituitary, thyroid, parathyroid, pancreas, adrenal, ovary and testis. / endocrine gland
All the endocrine glands responsible for coordinating the widespread activity of internal organs at a slower response rate than the nervous system. / endocrine system
Sex hormone produced by the anterior lobe of the pituitary. Stimulates sperm production in the male, and egg and oestrogen production in the female. / follicle stimulating hormone (FSH)
Organ in the body of an animal that secretes substances either for use by the body or for elimination (excretion). / gland
A hormone released by the pancreas. In humans it is broken down to glucose through the action of hormones, as more glucose is demanded for respiration. This hormone and insulin work together to control the level of sugar in the blood. / glucagon
Unsightly enlargement of the thyroid gland due to excessive production of the hormone thyroxine. / goitre
Hormones that act on or stimulate the gonads, e.g. FSH and LH. / gonad stimulating hormones
Results from an overactive thyroid. Thyroid enlarges (goitre), eyeballs protrude and there is an increased rate of metabolism, weight loss, increased blood pressure and nervousness. / Grave's disease
Produced by anterior (front) lobe of pituitary. An excess results in giantism and a deficiency results in dwarfism. / growth hormone
Chemicals produced in the meristematic regions and transported through the vascular system of plants. They affect the rate of growth (cell division) or development of plants when they are in very low concentrations. / (plant) growth regulators
Hormone secreted by an implanting fertilised egg (blastocyst). It maintains the corpus luteum in the ovary (until the ninth week of the gestation period, after which the placenta takes over) and prevents the breakdown of the endometrium. The analysis of urine for the presence of this hormone is used to confirm pregnancy. / HCG: human chorionic gonadotrophin
A substance (chemical message) produced by an endocrine gland secreted directly into and transported by the bloodstream to other parts (target organs) of the body where it brings about a response. They regulate metabolic activity. Their response generally works slowly over a longer period of time compared with a nervous response. / hormone
A hormone produced by the islets of Langerhans in the pancreas. It controls the blood sugar level, converts glucose to glycogen. A deficiency causes diabetes mellitus. / insulin
A group of cells in the pancreas that produce the hormone insulin. / islets of Langerhans
Sex hormone produced by the posterior lobe of the pituitary. Causes ovulation in the female on day 14 of a 28 day menstrual cycle and stimulates the corpus luteum to produce progesterone. In the male it stimulates the testes to produce testosterone. / luteinising hormone (LH)
A process which stops the synthesis of a hormone because the products of the reaction (another hormone) inhibit production of the first hormone that controlled its formation. / negative feedback
A female sex hormone produced by the ovaries.
·  Stimulates proliferation of uterine wall (endometrium).
·  Inhibits FSH production.
·  Stimulates LH production, and
·  Maintains the female secondary sexual characteristics. / oestrogen
A hormone produced by the posterior lobe of the pituitary gland in response to the sudden fall in the levels of oestrogen and progesterone. It stimulates contractions of the uterus during labour. / oxytocin
Endocrine glands found behind the thyroid gland in the neck. These glands secrete a hormone which regulates calcium reabsorption from the bones to the blood. / parathyroid
Master endocrine gland of the body situated at the base of the brain, produces hormones and controls other glands. / pituitary
A hormone produced by the ovaries. Stimulates endometrium growth in preparation for and during pregnancy. / progesterone
A hormone produced by the anterior lobe of the pituitary, which stimulates milk production in mammary glands (breasts) and inhibits FSH production by the pituitary. / prolactin
Involved in the manufacture of seminal fluid and provides nourishment and medium for sperm to swim. / prostate gland
A hormone secreted by the placenta. Relaxes the joints of the pelvic girdle and aids in the dilation of the cervix. / relaxin
Hormones produced in the gonads which promote the development and maintenance of the secondary sexual characteristics and structures. They also prepare the female for pregnancy, and aid in gamete formation. Males produce testosterone and females produce oestrogen and progesterone. / sex hormones
Any one of a number of compounds that have a common molecular structure. They have important physiological actions in the body and can be manufactured artificially to treat disease. Naturally occurring ones include the sex hormones, bile salts and progesterone. / steroid(s)
A structure or organ in a body on which a hormone has a specific effect, i.e. a muscle or a gland. / target organ
A hormone produced by the testes. Stimulates male secondary sexual characteristics. / testosterone
Endocrine gland found in the lower neck and upper chest. Produces hormones and lymphocytes prior to puberty. It degenerates after sexual maturity. / thymus
Large endocrine gland situated below larynx around trachea. Has two lobes. Absorbs iodine and joins it to a protein to form thyroglobulin and stored. Thyroglobulin converted to thyroxine when needed. / thyroid
Hormone produced by the pituitary gland which stimulates the thyroid gland to release thyroxine. Thyroxine increases cell metabolism. / thyroid stimulating hormone (TSH)
Hormone produced by the thyroid gland. Stimulates cells to use oxygen i.e. controls rate of respiration, therefore it controls metabolism.
Excess of this hormone causes Grave's disease.
Deficiency in an adult causes myxoedema whereas a deficiency in a child causes cretinism. / thyroxine
This hormone, produced by the pituitary, encourages the reabsorption of water in the nephron of the kidney. / vasopressin (antidiuretic hormone)

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