1. Endocrine System

2. Endocrine System
Endocrine System: a system of glands and tissues that secrete hormones to regulate the body.
In contrast to the exocrine system, which secretes its hormones using ducts
“Endocrine” derives from the Greek terms endo meaning inside and crinis meaning secrete

3. Endocrine System
Endocrine system is an information signal system, like the nervous system, but its effects and mechanisms are different.
Endocrine effects are slow to respond, taking days and even weeks to take effect, while the nervous system sends information much quicker

4. Hormones
Hormones are substances (chemical mediators) released from endocrine tissue into the bloodstream where they travel to target tissue and generate a response.
Hormones regulate various human functions, including metabolism, growth and development, tissue function, sleep, and mood.

5. Endocrine Glands
Endocrine glands are ductless; they secrete their hormones directly through the tissue fluid. From there, the hormones diffuse into the bloodstream for distribution throughout the body.

6. Endocrine glands (con’d)
The major endocrine glands
Hypothalamus
Pituitary Gland
Thyroid
Parathyroids
Adrenal Gland
Pancreas
Gonads
Thymus
Pineal Gland

7. Hormones fall into two basic classes that are later broken down:
Peptide hormones: includes proteins, amino acids, glycoproteins, and modified amino acids
Steroid hormones: includes the remainder which have the same four-carbon ring complex, but with different side chains

8. Hypothalamus

9. Hypothalamus Hormones PRODUCED
Hypothalamic-releasing and inhibiting hormones (only hormone actually released)
Antidiuretic: produced by Hypothalamus; released from posterior pituitary
Oxytocin: produced by Hypothalamus; released from posterior pituitary

10. Pituitary Gland

11. Pituitary Gland Split between two portions:
Anterior pituitary and Posterior pituitary

12. Anterior Pituitary Gland
Hormones:
Thyroid-stimulating: Glycoprotein; targets thyroid; stimulates thyroid
Adrenocorticotropic: Peptide; targets Adrenal cortex; stimulates adrenal cortex
Gonadotropic: Glycoprotein; targets gonads; Sex hormone production; egg and sperm production

13. Anterior Pituitary Gland (con’d)
Prolactin: Protein; targets mammary glands; Milk production
Growth: Protein; soft tissues, bones; Cell division; protein synthesis, bone growth
Melanocyte-stimulating: Peptide; targets melanocytes in skin; Regulates skin color in lower vertebrates

14. Posterior Pituitary Gland
Hormones:
Antidiuretic: Peptide; targets Kidneys; stimulates water reabsorption by kidneys
Oxytocin: Peptide; targets Uterus, mammary glands; stimulates uterine muscle contraction, release of milk by mammary glands

15. Thyroid Gland

16. Thyroid Gland Hormones:
Thyroxine: Iodinated amino acid; targets all tissues; Increases metabolic rate; regulates growth and development
Calcitonin: Peptide; targets bones, kidneys, intestines; Lowers blood calcium level

17. Parathyroid Glands

18. Parathyroid Gland
Hormones:
Parathyroid: Peptide; targets bones, kidneys, intestines; raises blood calcium level

19. Adrenal Glands

20. Adrenal Gland
Split between the Adrenal cortex and Adrenal medulla
Adrenal cortex releases:
Sex hormones: Steroid; targets gonads, skin, muscles, bones; stimulates reproductive organs and bring about sex characteristics
Glucocorticoids: Steroid; targets all tissue; raises blood glucose level; stimulates breakdown of protein
Mineralocorticoids: Steroid; targets kidneys; reabsorb sodium and excrete potassium

21. Adrenal Gland Adrenal medulla releases:
Epinephrine and norepinephrine: Modified amino acid; Targets cardiac and other muscles; released in emergency situations and raises blood glucose level

22. Adrenal Gland Hormones released:
Insulin: Protein; targets liver, muscles, adipose tissue; Lowers blood glucose level; promotes formation of glycogen
Glucagon: Protein; targets liver muscles, adipose tissue; raises blood glucose level

23. Pancreas
-Insulin: Protein; targets liver, muscles, adipose tissue; Lowers blood glucose level; promotes formation of glycogen
-Glucagon: Protein; targets liver muscles, adipose tissue; raises blood glucose level

24. Gonads

25. Gonads Stimulate male and female sex characteristics
Hormones released:
Androgens (Testosterone): released from Testes; Steroid; targets Gonads, ski, muscles, bones; stimulate male sex characteristics
Estrogens and Progesterone: released from ovaries; Steroid; targets Gonads, skin, muscles, bones, stimulate female sex characteristics

26. Thymus and Pineal Glands

27. Thymus and Pineal Glands
Thymosins: Peptide; targets T lymphocytes; stimulate production and maturation of T lymphocytes
Pineal:
Melatonin: Modified amino acid; targets brain; Controls circadian and circannual rhythms; possibly involved in maturation of sexual organs

28. Endocrine System

29. Homeostasis
Homeostasis: When the internal environment of a system is regulated in a stable condition with a relatively constant condition of properties
Endocrine and Nervous systems primarily work together to regulate the organs of the body and maintain homeostasis
Particularly influences digestive, cardiovascular, and urinary systems through homeostasis

30. Full Endocrine System