The body must send messages between cells and organs to coordinate activity and maintain homeostasis. This lesson compares the nervous and endocrine systems and introduces local chemical signaling.
Communication involves a sender transmitting signals to receivers to control or coordinate actions. The nervous and endocrine systems are the body's major long-distance communication systems and work together to help maintain homeostasis.
All flashcards
What is a hormone?
A chemical signal released by endocrine cells or organs into extracellular fluid and carried primarily by blood to cells with matching receptors.
How does neural signaling usually differ from endocrine signaling in speed and distance?
Neural signaling is typically rapid and local, often acting across a synaptic cleft. Endocrine hormones can travel long distances in blood, and their effects may begin quickly or take much longer.
What is autocrine signaling?
A cell releases a chemical that acts on that same cell, such as IL-1 acting on the cell that secreted it.
What is paracrine signaling?
A chemical messenger acts on nearby cells; for example, histamine can affect neighboring bronchial smooth muscle.
What does adenylyl cyclase produce when epinephrine activates a liver-cell membrane receptor?
It produces cyclic AMP (cAMP), a secondary messenger that relays and amplifies the signal inside the cell.
Quiz questions
Which types of signals does the nervous system use to communicate?Answer: Electrical and chemical signals
Why can a circulating hormone affect some cells but not others?Answer: Only cells with the appropriate receptor can respond to it.
Which statement accurately describes oxytocin's effects?Answer: It promotes uterine contractions during labor and contributes to breastfeeding.
Which description captures both endocrine and exocrine functions of the pancreas?Answer: It secretes insulin and glucagon and releases digestive juice through ducts.
What is the main clinical role of an endocrinologist?Answer: Diagnosing and treating disorders involving hormonal systems
Based on Anatomy and Physiology 2e by J. Gordon Betts, Kelly A. Young, James A. Wise, Eddie Johnson, Brandon Poe, Dean H. Kruse, Oksana Korol, Jody E. Johnson, Mark Womble, Peter DeSaix (OpenStax), licensed CC BY 4.0. Adapted into a summary, flashcards and quizzes.