The Endocrine System

The Endocrine System

• Endocrine’s latin parts mean inside secretion

• DEFINITION: the endocrine system is a system of ductless glands that secrete hormones directly into the bloodstream or lymph system for a specific physiological purpose or response

• The endocrine system is responsible for:– male and female differentiation (during puberty and in

the womb)– flight or fight response– sleep regulation– cellular metabolism– disease defense– energy regulation– reproduction

• All of the processes are controlled by the chemicals released from the glands called HORMONES

The organs of the endocrine system are spread throughout the body

Two types of hormone

Protein-like Hormones• Made of amino acids, just

like proteins• Can be very large in size• Are water soluble• Need receptors to pass

through the fatty cell membrane

• Ex: insulin

Fat-based Hormones• Also called steroids• Don’t dissolve in water or

plasma (blood)• Need transport proteins to

move through the blood stream• Pass easily through the fatty cell

membrane• Ex: cortisone, estrogen,

testosterone

Testosterone entering a target cell

Percy Julian(1899-1975)

-entered university at a time and place where public education for African-Americans only went up to the 8th grade

-used soy sterol to manufacture progesterone and testosterone, useful for troubled pregnancies, and a significant step forward in creating oral birth control

-invented a synthetic cortisone substitute that is used to treat arthritis

Hormones Activity• Each lab group will be assigned a hormone. Your job is to figure

out:– Where the hormone is produced (what organ or type of cell?)– What initiates release and/or production of the hormone– The target cell type for the hormone– The effect of this hormone on the target cell(s)– How the release of the hormone is regulated– How the hormone travels through the body and into the cells

• You will present this information to your classmates utilizing the organs scattered around the room to show the cycle of the hormone, from stimulation of production to regulation of level

• Signs and role-playing of different hormones or other signalers is mandatory!

Types of Steroid Hormones and How They Are Produced