The endocrine system
Sponsored Links
This presentation is the property of its rightful owner.
1 / 57

The Endocrine System PowerPoint PPT Presentation

  • Uploaded on
  • Presentation posted in: General

The Endocrine System. Hormones. Chemical substances secreted by endocrine (ductless) glands. These chemicals are carried by blood to their respective target cells. Tend to control slow long-term activities in the body. What would be a slow long-term process?. Primary Functions of Hormones.

Download Presentation

The Endocrine System

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

The Endocrine System


Chemical substances secreted by endocrine (ductless) glands. These chemicals are carried by blood to their respective target cells.

Tend to control slow long-term activities in the body.

What would be a slow long-term process?

Primary Functions of Hormones

  • Homeostasis

  • Growth and Development

  • Reproduction

  • Energy Metabolism

  • Behavior

Chemical Composition of Hormones





Some Protein/Polypeptide Hormones











glucose release from liver

glucagon from pancreas



blood glucose high

Negative Feedback Loop

blood glucose low

Biological Cycles


endocrine cell

receptor protein

target cell

Mechanism of Action on Target Cells

Water soluble hormone



endocrine cell

intracellular receptor

target cell

Mechanism of Action on Target Cells

lipid soluble hormone


Tropic Versus Nontropic Hormones

Tropic hormones- stimulate the production and secretion of hormones by other endocrine glands; ex. TSH

Nontropic hormones- stimulates cellular growth, metabolism, or other functions; ex. thyroxine


pineal gland

pituitary gland

thyroid gland

thymus gland

parathyroid glands

adrenal glands




Major Endocrine Organs

pineal gland


pituitary gland

Endocrine Organs of the Brain

Pineal Gland

Produces melatonin (synthesized from seratonin, a derivative of tryptophan)

  • Secreted directly in CSF to blood

  • High levels at night make us sleepy; low level during day

  • Pineal gland is stimulated by darkness and inhibited by light

  • Function in regulating circadian rhythms (sleep, body temp, appetite)  biological clock

The Pituitary Gland

Posterior Pituitary

Hormones of the Posterior Pituitary

Antidiuretic Hormone (ADH)



(+ feedback)



Anterior Pituitary

Hormones of the Anterior Pituitary

  • Growth Hormone (GH)

  • Thyroid Stimulating Hormone (TSH)

  • Adrenocorticotropic Hormone (ACTH)

  • Gonadotropins (FSH, LH)

  • Prolactin (PRL)

  • Melanocyte-stimulating Hormone (MSH)

Growth Hormone (GH)

  • Stimulates protein building

  • Stimulates cell growth (cell size and number), especially in muscle and bone.

  • Also stimulates fat breakdown.

strenuous exercise

GH Levels




hyposecretion of GH

Little People Big World

Kenadie - worlds smallest girl due to primordial dwarfism


hypersecretion of GH

Bao Xishun, a 7ft 8.95in herdsman from Inner Mongolia


hypersecretion of GH

7 ft 1 ¼ inches

Thyroid-Stimulating Hormone (TSH)

  • Acts on the thyroid gland, stimulating it to release T3 & T4

  • These thyroid hormones increase glucose catabolism and body heat production.

  • Regulated via negative feedback

Adrenocorticotropic Hormone (ACTH)

  • Acts on the adrenal cortex, stimulating it to secrete glucocorticoids (e.g., cortisol).

  • Helps make glucose from amino acids and fatty acids

  • Regulated via negative feedback

The Thyroid Gland




Thyroid Hormones

Thyroid gland selectively uptakes iodine to produce T3 & T4

  • Thyroxine (T4)

  • Triiodothyronine (T3)

  • Both control metabolic rate and cellular oxidation

  • Calcitonin - lowers blood Ca++ levels and causes Ca++ reabsorption in bone


Lack of iodine in diet

hyposecretion of T3 & T4

hyposecretion of T3 & T4


Myxedemahyposecretion of T3 & T4

After thyroid treatment



Parathyroid Glands

Parathyroid Hormone (PTH)

  • PTH release:

  • stimulates osteoclasts to reabsorb bone

Hyperparathyroidism- too much Ca++ drawn out of bone; could be due to tumor

Hypoparathyroidism- most often follow parathyroid gland trauma or after removal of thyroid--- tetany, muscle twitches, convulsions; if untreatedrespiratory paralysis and death

The Pancreas

  • Pancreas:

  • Regulates glucose uptake by cells

  • Controlled via negative feedback: insulin & glucagon

  • Blood sugar level: 90 mg/mL


alpha cells

beta cells

Islets of Langerhans


  • Produced by the  cells of the Islets of Langerhan

  • Catalyze oxidation of glucose for ATP production

  • Lowers blood glucose levels by promoting transport of glucose into cells.

  • Stimulates glucose uptake by the liver and muscle cells.

  • Stimulates glycogen synthesis in the liver and muscle cells.

  • Also stimulates amino acid uptake and protein synthesis of muscle tissue


  • Produced by the  cells of the Islets of Langerhans

  • Stimulates change of glycogen to glucose in the liver.

  • Synthesis of glucose from lactic acid and non carbohydrate molecules such as fatty acids and amino acids

  • Causes  in blood glucose concentration

hypoglycemic- low blood sugar; deficient in glucagon

Diabetes Mellitus

Type I Diabeteshyposecretion of insulininsulin dependantjuvenile onsetType II Diabeteslate onset (adult)insensitivity of cells to insulinmanage by exercise & diet

Symptoms (Type I):

  • sugar in blood and urine

  • urinate too often and produce too much urine

  • Too thirsty

  • Too hungry

Type I (IDDM):

  • Arteriosclerosis

  • Cardiovascular problems

  • Gangrene

  • Eye problems

  • Kidney damage


  • Insulin replacement

  • Pancreas transplant

  • Pancreatic cell transplant

  • Fetal pancreatic islet cell transplant

Adrenal Glands

Hormones of the Adrenal Medulla

  • Adrenalin (epinephrine): converts glycogen to glucose in liver

  • Noradrenalin(norepinephrine): increases blood pressure

  • (sympathetic nervous system)

    • Corticosteroids: glucose levels)

  • Hormones of the Adrenal Cortex

    • Glucocorticoids- cortisol

    • Decrease protein synthesis

    • Increase release and use of fatty acids

    • Stimulates the liver to produce glucose from non carb’s

    • Mineralcorticoids- aldosterone

    • Stimulates cells in kidney to reabsorb Na+ from filtrate

    • Increases water reabsorption in kidneys

    • Increases blood pressure

    • Sex Steroids- small amts (androgens)

    • Onset of puberty

    • Sex drive

    Cushing’s Syndrome

    Hypersecretion of cortisone; may be caused by an ACTH releasing tumor in pituitary

    Symptoms: trunkal obesity and moon face, emotional instability

    Treatment: removal of adrenal gland and hormone replacement

    Addison’s Disease

    Hyposecretion of glucocorticoids and mineral corticoids;

    Symptoms- wt loss, fatigue, dizziness, changes in mood and personality, low levels of plasma glucose and Na+ levels, high levels of K+

    Treatment- corticosteroid replacement therapy


    Located anterior to the heart

    Produces- thymopoetin and thymosin helps direct maturation and specialization of T-lymphocytes (immunity)


    Ovaries- produce estrogen and progesteroneresponsible for maturation of the reproductive organs and 2ndary sex characteristics in girls at puberty

    Female Reproductive System


    Testes- produce sperm and testosterone (initiates maturation of male repro organs and 2ndary sex characteristics in boys at puberty)


    • A disease in which too much T3 and T4 are produced.

    • The posterior pituitary produces which two hormones and what is their function?

    • What is acromegaly?

    • What organ does glucagon target?

    • The target tissue for lutenizing hormone is ____.

    • Where are epinephrine and norepinephrine produced?

    • If your adrenal cortex produced low levels of aldosterone, your urine would be _____?

    • What effect does parathyroid hormone have on your bones?

  • Login