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4.03/4.04 Remember the structures and understand the functions of the

endocrine system

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4.03/4.04 Remember the structures and understand the functions of the

ENDOCRINE SYSTEM

What are the structures of the endocrine system?

What are the functions of the endocrine system?

How do you relate the body’s hormones to the endocrine system?

4.04 Understand the functions and disorders of the endocrine system

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4.03 Remember the structures of the endocrine system

*Gland (endocrine/exocrine)

any organ that produces a secretion (hormone/chemical)

Endocrine glands -organized groups of tissues that use materials from the blood and lymph to make new compounds called hormones

-also called ductless glands; the hormones are secreted directly into the blood stream

4.03 Remember the structures of the endocrine system

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Exocrine glandsAnother type of gland in which secretions must go

through a duct.

-the duct carries the secretion to a body surface or organ

-exocrine glands include sweat, salivary, lacrimal, and pancreas

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Function of the Endocrine System

Human behavior is shaped by the endocrine system and the nervous system working together.

*Hormone release provides immediate body responses because the hormones are directed toward target organ cells.

64.04 Understand the functions and disorders of the endocrine system

Functions of the ENDOCRINE SYSTEM

Hormone ControlHormone Control (negative feedback)

Occurs when there is a drop in the level of a hormone.

The drop triggers a chain reaction of responses to increase the amount of hormone in the blood.

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Major glands of the endocrine system

1. Pituitary

2. Pineal

3. Thyroid

4. Parathyroid

5. Thymus

6. Adrenals

7. Gonads

8. Pancreas

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The *Pituitary Gland

Known as : The Master Gland because of it’s major influence on the body’s activities

Size of a grape

*Located at the base of the brain4.03 Remember the structures of the

endocrine system

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The Pituitary Gland

The pituitary gland and its hormones

*Anterior lobe – produces 6 hormones

*Posterior lobe – produces 2 hormones

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Anterior Pituitary Lobe

1. *Growth hormone (GH)

responsible for growth and development

* also helps fat to be used as energy, saving glucose and helping to maintain blood sugar levels.

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Anterior Pituitary Lobe

2. *Prolactin Hormone

develops breast tissue and stimulates the production of milk after childbirth

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Anterior Pituitary Lobe

3. Thyroid stimulating hormone (TSH)

Stimulates the growth and secretion of the thyroid gland

4. Adrenocorticotropic hormone (ACTH)

Stimulates the growth and secretion of the adrenal cortex

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Anterior Pituitary Lobe

5. Follicle-stimulating hormone (FSH)

Stimulates the growth of the graafian follicle and the production of estrogen in females, and stimulates the production of sperm in the male.

6. Luteinizing hormone

Stimulates the growth of the graafian follicle and the production of estrogen and the formation of the corpus luteum after ovulation, which produces progesterone in the female. In the male, it is necessary for the production of testosterone.

144.04 Understand the functions and disorders of the endocrine system

*Posterior Pituitary Lobe

1.1.Vasopressin – Anti-diuretic Vasopressin – Anti-diuretic hormone (ADH)hormone (ADH)

Maintains water balance by Maintains water balance by reducing urinary outputreducing urinary output

2.*OxytocinOxytocin

Promotes milk ejection and causes Promotes milk ejection and causes contraction of the smooth contraction of the smooth muscles of the uterusmuscles of the uterus

**a synthetic derivative of this a synthetic derivative of this hormone (oxytocin) could be hormone (oxytocin) could be given to induce laborgiven to induce labor

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Pineal Gland• Located in the 3rd ventricle in the brain

• Small pinecone shaped organ

• Produces the hormone melatonin.

• There are no clear answers as to the function of melatonin; however, melatonin causes body temperature to drop.

Falling asleep is associated with lowered body temperature.

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*Thyroid Gland- Butterfly shaped- -Located in the anterior neck

on either side of the larynx, over the trachea

- *Secretes thyroxine, triiodothyronine, and calcitonin

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Thyroid Gland

Thyroxine – controls the rate of cellular metabolism, heat production, and oxidation of all cells.

Calcitonin – Maintains proper calcium level in the bloodstream

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Parathyroid Glands

-Four glands; Size of a grain of rice

-Attached to the posterior thyroid

-Secretes the hormone parathormone which, like calcitonin, also controls the concentration of calcium in the bloodstream.

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*Thymus Gland-Serves both the endocrine system and the lymphatic system

-*Located under (posterior) the sternum

-Large during childhood but disappears with age. (puberty)

-Secretes hormone, thymosin, which helps to stimulate the lymphoid cells that are responsible for the production of T cells, which fight certain diseases

*The thymus is critical to the development of the immune system

4.03 Remember the structures of the

endocrine system

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*Adrenal GlandThere are two adrenal glands.

-*One is located on top of each kidney.

- *Each gland has two parts:

1. *Cortex – outside (stimulated by ACTH) – hormones secreted by the adrenal cortex are known as corticoids which are very effective as anti-inflammatory drugs.

The cortex secretes 3 groups of corticoids:

*Mineralocorticoids-aldosterone (reabsorption)

*Glucocorticoids-increase glucose in the blood

*Androgens (male sex hormones) 4.03 Remember the structures of the endocrine system

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Adrenal Gland

2. *Medulla – inside – secretes epinephrine (adrenalin), a powerful cardiac stimulant, and norepinephrine.

*The adrenal medulla responds to the sympathetic nervous system. The hormones produced are referred to as the “fight-or-flight” hormones, because they prepare the body for an emergency. The adrenalin (EPINEPHRINE) causes the heart rate, respiratory rate, and blood pressure to increase, and mental alertness increases.

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GonadsSex glands

Testes (male) – responsible for producing sperm and the hormone testosterone.

- Produced by the interstitual cells of the testes, *testosterone is responsible for the development of the male reproductive organs and secondary male characteristics. (beard and body hair, deepening of the voice, increase in musculature, and the production of sperm.)

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GonadsSex glands:

Ovaries (female) – responsible for producing the ova or egg and the hormones estrogen and progesterone.

*Estrogen – stimulates the development of the reproductive organs, including the breast, and secondary sex characteristics such as pubic and axillary hair, prepares for menstruation.

Progesterone – works with estrogen to build up the lining of the uterus for the fertilized egg

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*Pancreas*Located behind the stomach; also

a digestive organ

Both an endocrine and exocrine gland

The endocrine portion is involved in the production of insulin (regulates blood glucose) by the B cells of the Islets of Langerhans

*Contains the Islets of Langerhans-specialized cells in the pancreas that produce insulin

*Lack of insulin secretion by the islet cells causes diabetes mellitus.

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4.03 Remember Structures of theendocrine system

4.04 Understand the Functions of the endocrine system

4.03 Remember the structures of the endocrine system

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