Endocrine System and Hormone Regulation Vocabulary
Lab Logistics and Practical Examination Details
- Upcoming Practical Exam: July 21.
- This practical is not next week, but the following week.
- Topics Included: The eye, the ear, the endocrine system, blood, and blood typing.
- Preparation Activities:
- A mock practical is scheduled for the Thursday before the actual practical to assist in self-assessment.
- Students are encouraged to spend time with the lab models, practice labeling individual structures, and quiz partners.
- For the eye and ear sections, students must be able to identify specific structures (ID structure).
- For the endocrine section, students must identify the organ and potentially list a hormone produced by that organ.
- Model Identification: One or two cow eyeballs will be used on the practical; students will be required to identify specific structures marked with labels.
- PowerPoint/Study Guide Assignment:
- Label endocrine organs based on the list provided in the module.
- For each organ slide, include:
- The name of the hormone produced (one per organ is sufficient).
- The stimulus for hormone release.
- The target organ or tissue.
- The physiological effect.
- Alternatively, students may create a comprehensive table containing these four categories at the end of their PowerPoint.
- Next Session: The next lab will begin with a quiz on the endocrine material covered today, followed by instructions on blood and blood typing.
Introduction to the Endocrine System
- Definition: The endocrine system consists of ductless organs that release hormones directly into the bloodstream.
- Comparison with Exocrine System: Unlike the endocrine system, the exocrine system (e.g., sweat glands, sebaceous glands) utilizes ducts to transport secretions.
- Role in Homeostasis: Both the endocrine and nervous systems cooperate to maintain metabolism and internal homeostasis.
- Hormone Transport Categories:
- Autocrine: A hormone that acts on the same cell that released it; the hormone binds to receptors on the originating cell.
- Paracrine: A short-distance hormone that travels to and affects nearby cells.
- Circulating: Hormones that enter the blood and travel long distances from their site of release to target tissues throughout the body.
Comparison of the Nervous and Endocrine Systems
| Feature | Nervous System | Endocrine System |
|---|
| Messenger | Neurotransmitters | Hormones |
| Transmission Pathway | Electrical impulses traveling across long axons | Travel through the blood |
| Speed of Transmission | Fast/Quick | Slower/On the slower end |
| Duration of Effect | Short-term/Quick | Long-term |
| Response Range | Localized to a specific area | Widespread/Can be localized |
| Requirement for Persistence | Needs constant firing of signals/stimulus | Hormones persist longer in the system |
| Regulation | Regulated by negative feedback | Regulated by negative feedback |
Anatomy and Hormones of the Brain
- Hypothalamus: Often described as "running the show."
- Function: Produces Releasing Hormones (RH) and Inhibiting Hormones (IH) that regulate other glands.
- Specific Hormones Produced:
- Antidiuretic Hormone (ADH): Designed to maintain water balance; results in less frequent urination.
- Oxytocin: Plays a critical role in labor by relaxing/contracting the muscular walls of the uterus to facilitate birth.
- Sympathetic Control: Regulates the sympathetic output to the adrenal medulla (controlling epinephrine and norepinephrine release).
- Pituitary Gland: Located within the Sella Turcica (a horse-saddle-shaped portion of the anterior fossa of the skull);