If you were not here Friday, or if you lost yours, here is a copy of the homework that will be due when we return from break. The questions are on the ENDOCRINE SYSTEM.
Remember, when we come back you will have an exam on both the endocrine and the reproductive system.
What you need to know about the endocrine system to answer these questions:
*The endocrine system is made of glands, which secrete hormones.
*Hormones are chemical messages that deliver the message only to specific target cells with matching receptor molecules.
*If a cell has the matching receptor molecule, it will read the message and make a change.
*If a cell does NOT have a receptor molecule, it will NOT receive the message
*The pancreas is an organ that secretes insulin. Insulin REGULATES BLOOD SUGAR LEVELS. When blood sugar (glucose) levels get too high, insulin is released by the pancreas. When blood sugar is back to normal, insulin secretion STOPS.
*When one change leads to another in order to maintain homeostasis, it is called a FEEDBACK MECHANISM.
Feedback mechanisms examples- sweating and body temperature, insulin and blood sugar levels, exercise and heart rate, and plant guard cells and water loss.
*The NERVOUS SYSTEM is another body system that uses chemical messages (not hormones) and receptor molecules to communicate.