THE ENDOCRINE SYSTEM NOTES-CHAPTER 10

Endocrine System

A system that, along with the nervous system, helps maintain homeostasis in the human body.

Glands

Collections of epithelial tissue that secrete hormones into the bloodstream.

Target Cells

Specific cells or organs that are stimulated by hormones.

Exocrine Glands

Glands that release their products through a duct onto a body surface.

Homeostasis

The maintenance of a stable internal environment within the body.

Hormones

Chemical substances secreted by glands that regulate metabolic functioning of cells and organs.

Amino Acid-based Hormones

Hormones made of varying sizes of amino acids; most human hormones fall into this category.

Steroid-based Hormones

Hormones synthesized from cholesterol, including gonadal and adrenocortical hormones.

Eicosanoids

Hormones typically released by cell membranes; involved in inflammation and allergic reactions.

Negative Feedback System

A mechanism that regulates hormonal secretion to prevent hyposecretion and hypersecretion.

Hyposecretion

Deficient production of hormones.

Hypersecretion

Excessive production of hormones.

Pituitary Gland

The gland located in the Sella Turcica of the sphenoid bone, often referred to as the 'Master Gland'.

Adenohypophysis

The anterior lobe of the pituitary gland that secretes several important hormones.

Growth Hormone (GH)

A hormone that regulates the growth of the skeleton.

Gigantism

Hypersecretion of GH during the growing years, leading to excessive growth.

Acromegaly

Hypersecretion of GH in adults, causing enlargement of hands, feet, and face.

Pituitary Dwarfism

Hyposecretion of GH that results in a person being only 3-4 feet tall.

Thyroid Stimulating Hormone (TSH)

A hormone that stimulates secretions from the thyroid gland.

Adrenocorticotrophic Hormone (ACTH)

A hormone that stimulates hormonal secretions of the adrenal glands.

Gonadotrophins

Hormones that include Follicle-Stimulating Hormone (FSH) and Lutenizing Hormone (LH), regulating sex organs.

Prolactin (PRL)

A protein hormone that stimulates breast development and milk secretion.

Oxytocin (OT)

A hormone that regulates blood pressure and stimulates uterine contractions during childbirth.

Antidiuretic Hormone (ADH)

A hormone that regulates water balance in the kidneys.

Diabetes Insipidus

A condition resulting from hyposecretion of ADH, causing excessive urine production.

Thyroid Gland

A gland located in the neck that secretes hormones including thyroxine and calcitonin.

Thyroid Hormone (TH)

Hormones that increase the body’s metabolic rate, including thyroxine and triiodothyronine.

Calcitonin (CT)

A hormone that removes calcium from the blood and deposits it in the bones.

Myxedema

A condition resulting from hyposecretion of thyroid hormone in adults.

Goiter

An enlarged thyroid gland.

Cretinism

Hypothyroidism in infants that can lead to severe mental and physical retardation if untreated.

Grave's Disease

A condition resulting from hypersecretion of thyroid hormone, leading to weight loss and increased heart rate.

Parathyroid Hormone (PTH)

The only hormone secreted by the parathyroid glands that increases calcium levels in the bloodstream.

Adrenal Glands

Pyramid-shaped glands sitting on the kidneys, consisting of cortex and medulla regions.

Mineralocorticoids

Hormones that regulate electrolyte concentrations, especially sodium and potassium levels.

Aldosterone

The most abundant mineralocorticoid that regulates sodium levels in the body.

Addison Disease

A condition caused by hyposecretion of adrenal cortex hormones.

Cushing Syndrome

A condition caused by hypersecretion of adrenal cortex hormones.

Epinephrine

A hormone associated with the 'Fight or Flight' response, secreted by the adrenal medulla.

Glucagon

An amino acid hormone produced in the pancreas that stimulates the liver to convert glycogen into glucose.

Insulin

A protein hormone produced in the pancreas that lowers blood sugar levels.

Diabetes Mellitus

A condition resulting from hyposecretion of insulin, leading to high blood sugar levels.

Estrogen

A hormone secreted by the ovaries that stimulates the development of female secondary sex characteristics.

Testosterone

A hormone secreted by the testes that stimulates the development of male secondary sex characteristics.

Melatonin

A hormone secreted by the pineal gland that regulates diurnal rhythms and sleep patterns.

Thymosin

A hormone secreted by the thymus gland that regulates lymphocyte production.