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