Endocrine System

An organ system

AIM

•What is a “hormone” and how does it affect target cells?

Body System (organ system) Review

• Respiratory-

Body System (organ system) Review

• Respiratory- breathing system for cellular respiration

• Circulatory- transportation system• Digestive- breaks down food into organic

monomers for cellular respiration• Immune- defense system against foreign pathogens• Endocrine- Cellular communication system

Endocrine System

• The endocrine system is made up of glands that release chemical messages into the bloodstream.

• These chemicals are called hormones

Hormones

• Chemicals that travel through the bloodstream and affect the activity of other cells.

• Hormones only affect specific cells.• The cells that a particular hormone affects are

called target cells.

Receptor Molecules• A hormone will only affect cells with matching

receptor molecules on their surface.

• If a cell does not have the special receptor molecule, the hormone will not affect the cell.

Hormones are… SPECIFIC• We’ve officially learned all of the “specifics!”

• WHAT ELSE IS “SPECIFIC”???

The SPECIFICS

• Enzymes catalyze a SPECIFIC chemical reaction and fit like a lock and key with a SPECIFIC substrate

• AntiBodY fits SPECIFIC antigen!

• Receptor molecules fit SPECIFIC hormones!

DRAW IN BOXES

• Enzyme/substrate• Antibody/antigen• Hormone/Receptor Molecule

Receptor Molecules

• When a hormone is accepted by a specific receptor molecule, the target cell will respond to the message.

• Responses to hormones are usually slow and long lasting. Changes in the cell take place over time.

Glands of the Endocrine System

• There are various glands around the human body that secrete hormones into the blood stream.

• Secrete- release, “leak into”

Pituitary GlandThyroidPancreasAdrenal GlandsPancreasOvariesTests

Pituitary GlandThyroid

Pancreas

OvariesTestes

Adrenal Glands

Homeostasis

• Hormones are secreted to cause changes that help maintain homeostasis