MT M 4.1 Endocrine Flashcards
endocrine system
The endocrine system of the body controls the secretion of hormones from several glands located throughout the body.
Glands
Glands are organs that secrete or release hormones into the bloodstream.
Hormones
Hormones are chemical substances that are released from the glands in small amounts and travel through the blood to other tissues and organs. They transfer information and instructions from one area of the body to another area.
Glands and hormones
Glands and hormones influence almost every cell, organ, and function of the body. Growth and development, tissue function, metabolism, homeostasis, sexual function, and mood are all influenced and regulated by hormones.
Endocrinology
Endocrinology is the study of the endocrine system, and it is a subspecialty of internal medicine. An endocrinologist is a physician that diagnoses and treats the conditions of the endocrine system.
endocrinologist
An endocrinologist is a physician that diagnoses and treats the conditions of the endocrine system.
Pituitary
Gland
Brain- Master gland, regulates other endocrine glands
Pineal
Gland
Brain- Regulates sleep
Thyroid
Gland
Neck- Metabolism, growth, and development
Parathyroid
Gland
Neck- Maintains calcium and phosphate levels
Pancreas
Gland
Epigastric area of the abdomen –Blood glucose regulation
Adrenals
Gland
Abdomen, above the kidneys – Regulates sodium and potassium, carbohydrate metabolism, sex hormones, and epinephrine secretion in emergencies
Ovaries, Testes
Gland
Pelvis – Male and female secondary sexual characteristics
Thymus
Gland
located in the Mediastinum in front of the heart – Regulates the immune system
pituitary gland
The pituitary gland is located at the base of the brain, as seen in Figure 4.1. This gland is considered the master gland, as it regulates the other glands of the endocrine system. The pituitary gland can be divided into anterior and posterior sections.
adenohypophysis
The anterior portion of the pituitary gland is called the adenohypophysis, and it secretes different hormones than the posterior portion of the gland
neurohypophysis
The pituitary gland posterior portion of the gland, which is called the neurohypophysis.
Growth hormone (GH)
adenohypophysis secretes
Growth hormone (GH), which regulates the growth and development of the bones and muscles, and other organs.
Adrenocorticotropin hormone (ACTH)
adenohypophysis secretes
Adrenocorticotropin hormone (ACTH), which regulates the growth of the adrenal cortex.
Thyroid-stimulating hormone (TSH),
adenohypophysis secretes
Thyroid-stimulating hormone (TSH), which stimulates the growth of the thyroid gland.
Follicle-stimulating hormone (FSH) and luteinizing hormone (LH)
adenohypophysis secretes
Follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which control the sex glands in males and females.
Melanocyte-stimulating hormone,
adenohypophysis secretes
Melanocyte-stimulating hormone, which controls skin pigmentation.
Prolactin hormone,
adenohypophysis secretes
Prolactin hormone, which stimulates the growth and development of the mammary glands.
antidiuretic hormone (ADH)
neurohypophysis secretes
The neurohypophysis secretes antidiuretic hormone (ADH), which regulates the secretion or reabsorption of water in the kidneys,
oxytocin
neurohypophysis secretes
oxytocin, which stimulates the uterus to contract during childbirth and the release of milk from the mammary glands.
pineal gland
The pineal gland is located in the brain, as seen in Figure 4.1. It is a small gland that secretes melatonin and serotonin.
Melatonin
Melatonin is important in the regulation of the body’s sleep-wake cycle.
Serotonin
Serotonin stimulates the nervous system by regulating neurotransmitters, smooth muscles, and gastric secretions.
thyroid and parathyroid glands
The thyroid and parathyroid glands are both located in the neck. Their locations are shown in Figure 4.1.
thyroid gland
The thyroid gland is a larger gland in the neck, anterior to the trachea. It secretes hormones that are involved in metabolism.
thyroxine (T4)
hormones that are secreted by the thyroid gland
T4 maintains and regulates the basic metabolic rate of the body, growth and development of the body, and metabolism of nutrients, water, vitamins, and minerals.
triiodothyronine (T3)
hormones that are secreted by the thyroid gland
T3 also regulates the basic metabolic rate.
calcitonin
hormones that are secreted by the thyroid gland
Calcitonin is involved in bone and calcium metabolism
parathyroid glands
The parathyroid glands are located on the thyroid gland in two pairs: a superior pair and an inferior pair.
parathyroid
parathyroid glands secrete
The parathyroid glands secrete parathyroid hormone (PTH), which is involved in maintaining calcium levels and the metabolism of phosphorus.
The pancreas and the gastrointestinal mucosa
The pancreas and the gastrointestinal mucosa are organs that are a part of the digestive system. However, they both have a role in the endocrine system, as they both secrete hormones. The pancreas is located in the abdomen, as seen in Figure 4.1.
pancreas
endocrine portion
The endocrine portion of the pancreas consists of cell clusters called islets of Langerhans
islets of Langerhans
pancreas endocrine portion
The endocrine portion of the pancreas consists of cell clusters called islets of Langerhans. The islets of Langerhans secrete the hormones insulin, glucagon, and somatostatin.
Insulin
pancreas endocrine portion
Insulin stimulates the cells of the body to take in glucose from the bloodstream for metabolism.
Glucagon
pancreas endocrine portion
Glucagon increases the blood glucose level by breaking down glycogen into glucose
Somatostatin
pancreas endocrine portion
Somatostatin decreases the production of both insulin and glucagon.
gastrointestinal mucosa
The epithelial lining of the stomach and intestines, called the gastrointestinal mucosa, secretes several hormones related to digestion.
Gastrin
gastrointestinal mucosa
Gastrin stimulates the production of gastric acid in the stomach, which breaks down food.
Secretin
gastrointestinal mucosa
Secretin stimulates the secretion of pancreatic enzymes, bile, and other secretions from the intestines that also are involved in the digestion of food.
Cholecystokinin
gastrointestinal mucosa
Cholecystokinin controls the gallbladder
enterogastrone
gastrointestinal mucosa
enterogastrone regulates secretions from the stomach.
adrenal glands
The adrenal glands are two glands that are located in the abdomen, on top of the kidneys.
adrenal cortex
The adrenal glands
The adrenal cortex is the outer portion of the adrenal gland, and it secretes three different types of hormones: glucocorticoids, mineralocorticoids, and androgens.
glucocorticoids
The adrenal glands adrenal cortex
Glucocorticoids are hormones that are involved in carbohydrate metabolism. The main glucocorticoid hormones are cortisol and corticosterone.
Aldosterone
The adrenal glands adrenal cortex
Aldosterone is the main mineralocorticoid hormone, and it is involved in the regulation of electrolytes and fluid balance. Androgens are hormones that stimulate the development of male sexual characteristics, and they are testosterone and androsterone.
adrenal medulla.
The adrenal glands adrenal medulla.
The inner portion of the adrenal gland is called the adrenal medulla.
catecholamines
The adrenal glands adrenal medulla.
The hormones produced here are called catecholamines, and they are involved in nervous system regulation.
Dopamine, epinephrine, and norepinephrine
The adrenal glands adrenal medulla.
Dopamine, epinephrine, and norepinephrine are three crucial hormones that are involved in sympathetic nervous system function.
ovaries
Reproductive Organs
The ovaries produce estrogen and progesterone, two hormones that are involved in the regulation of the female sex organs.
Reproductive Organs
The female ovaries and male testes are seen in
testes
Reproductive Organs
The testes produce testosterone, which is involved in the regulation of the male sex organs.
placenta
Reproductive Organs
An additional temporary endocrine organ is the placenta, which is produced during pregnancy. The placenta secretes hormones involved in the growth and development of the fetus.
thymus
The thymus is a gland that is located in the mediastinum in front of the heart. It is shown in Figure 4.1. It secretes hormones that are involved in the function of the immune system. These hormones are thymosin and thymopoietin.
