The Endocrine System

Chapter 39

Coordination of body systems by

Chemical control of hormones

I A. Systems that chemically coordinate the body:

NERVOUS

ENDOCRINE

• Stimuli-response• Rapid response• Short time

• Stimuli-response• Slow response• Lasts long time• Both=HOMEOSTASIS

B.Components of the Endocrine system

1. Glands make ?

Hormones or chemical messengers

2. Travel through ?

Blood stream

(Ductless glands)

3. To where ?

Specific Target Organs

Pituitary

ThyroidThymus

AdrenalPancreas

OvariesTestes

Feedback thermostat . . . . . . .

Feed back loop . . . . . . . High Blood sugar• Pancreas makes

insulin• Sugar enters the

cells• Blood sugar

lowered

Low Blood sugar• Pancreas makes

glucagon

• Sugar leaves the liver

• Blood sugar is increased

High Blood sugar

Pancreas makes Insulin

= Sugar goes into the cell

Low BloodSugar

GlucagonReleasesSugarFromliver Cell needs

sugar

2 Categories of Hormones

• Steroid Hormones

• Non-Steroid Hormones

IIA.Hypothalamus: Brain area that controls the Master Gland: Pituitary

Also controls oxytocin for uterus contraction & ADH for water balance in the kidneys

Pituitary:The Master Gland that controls other endocrine glands

Makes• TSH Thyroid

stimulating hormone for

metabolism• LH & FSH for

Reproduction• GH Growth hormone• ACTH hormone• Oxytocin• Prolactin• ADH• MSH

Thyroid: controls metabolism with thyroxine hormone

• Pituitary gland controls the thyroid with TSH

• Iodine is important for the thyroid tissue

• Goiter results from lack of iodine

• Also releases calcitonin

Parathyroid Thymus

Adrenal Medulla makes epinephrine & norepinepthrine

• Adrenal gland sits on top of the kidney

• Controls “fight or flight” response

• Superhuman strength @ adrenaline

Pancreas: Regulates sugar balance

• Insulin =

sugar into cells

• Glucagon =

sugar leaves the liver

Insulin sources for diabetics :

• From domestic livestock

• Genetically engineered bacteria

Examples of hormones & glands...

• Mammary glands prolactin

• Ovaries makeestrogen

• Testes maketestosterone

• Adrenal makeadrenaline