Endocrine System

Endocrine System

System of ductless glands that secrete hormones

Messenger Molecules

Hormones in the Endocrine System are known as

Blood

Hormones in the Endocrine System circulate in the

Target Cells

Respond to the hormones for which they have receptors

Purely Endocrine Organs

Pituitary Gland, Pineal Gland, Thyroid Gland, Parathyroid Gland, Adrenal Glands

Cortex and Medulla

2 Adrenal Glands

Endocrine Cells in Other Organs

Pancreas, Thymus, Gonads, Hypothalamus

Pituitary Gland

Sits in the hypophyseal fossa; depression in sella turcica or sphenoid bone

9 Hormones

Pituitary gland secretes _____

Adenohypophysis

Anterior Pituitary

Neurohypophysis

Posterior Pituitary

Hormones in the Anterior Pituitary

TSH, ACTH, FSH, LH, GH, PRL, MSH

Hormones in the Posterior Pituitary

ADH, Oxytocin

Tropic Hormones

TSH, ACTH, FSH, LH; Regulate functions of other hormones

Pineal Gland

a serotonin derived hormone which modulates sleep patterns; a small endocrine gland in the brain; situated beneath the back part of the corpus callosum

Melatonin

Produced by the pineal gland

Thyroid Gland

Produces hormones that regulate the body's metabolic rate, controlling heart, muscle and digestive function, brain development, and bone maintenance

T4- Thyroxine and T3- Triiodothyronine

Produced by the Thyroid Gland; Basal metabolic hormone.

Parathyroid Gland

Increases blood Ca+++ concentration when it gets too low

Adrenal Glands

Produces hormones including adrenaline and steroids, aldosterone and cortisol

Adrenal Glands

Also known as suprarenal glands

Pancreas

Secretes hormones that regulate the level of glucose in the blood, and prevents the release of insulin and glucagon

Insulin, Glucagon, Somatostatin

Main hormones secreted by endocrine gland in the pancreas

Somatostatin

Prevents the release of insulin and glucagon; Works to stop the pituitary gland from releasing certain hormones, including growth hormones and TSH.

Insulin and Glucagon

Regulate level of glucose in the blood

Insulin

a hormone that helps regulate the amount of sugar, or glucose, in the blood.

Thymus

Secretes thymosin, thymopoietin, and thymulin

Thymosin

Hormone that programs T lymphocytes.

Cytoplasm

The three major thymus hormones are thought to reside in the ____ of the thymus epithelial cell

Gonadal Hormones

Produced by human gonads

Gonads

Testes and Ovaries

Androgen, Estrogen, Progestin

Primary hormones produced by gonads

Testosterone

Primary androgen that plays a critical role in the development of the primary and secondary male sex characteristics, as well as in spermatogenesis. 

Estradiol and Progesterone

Primary female hormones, which are responsible for egg development, the menstrual cycle, and breast development.

Hypothalamus

Endocrine Glands that secretes Corticotropin-releasing hormone (CRH), Gonadotropin-releasing hormone (GnRH), Thyrotropin-releasing hormone (TRH), Somatostatin, Oxytocin, and Vasopressin

Corticotropin-releasing hormone (CRH)

Involved in the body’s response to both physical and emotional stress. It signals the pituitary gland to produce

Adrenocorticotropic Hormone (ACTH)

Triggers production of cortisol, an important stress hormone

Gonadotropin-releasing hormone (GnRH)

Causes the pituitary gland to produce important reproductive hormones, such as follicle-stimulating hormone (FSH) and luteinizing hormone (LH)

Thyrotropin-releasing hormone (TRH)

Stimulates the pituitary gland to produce thyroid-stimulating hormone (TSH)

Thyroid-Stimulating Hormone (TSH)

Plays an important role in the function of many body parts, such as the muscles, heart, and gastrointestinal tract; This is one example of a tropic hormone.

Oxytocin

This hormone controls many important behaviors and emotions, such as sexual arousal, trust, recognition, and maternal behavior.

Vasopressin

Also called antidiuretic hormone (ADH) - regulates water levels in the body. When vasopressin is released, it signals the kidneys to absorb water.; Hypothalamic hormone important in regulating water balance.

Calcitonin

Involved in helping to regulate levels of calcium and phosphate in the blood, opposing the action of parathyroid hormone.

Glucagon

Acts antagonistically to insulin; produced by the same endocrine organ. B

Epinephrine or Adrenaline

Example of short-term stress hormone

Aldosterone

Adrenal cortex hormone involved in regulating salt levels of body fluids.

Prolactin

A hormone necessary for milk production.

Luteinizing Hormone (LH)

This hormone plays in the regulation of ovarian cycle.

ACTH

Adrenocorticotropic Hormone

TSH

Thyroid-Stimulating Hormone

FSH

Follicle-Stimulating Hormone

LH

Luteinizing Hormone

GH

Growth Hormone

PRL

Prolactin

MSH

Melanocyte-Stimulating Hormone

ADH

Antidiuretic Hormone