1. WARM-UP RECALL TO CHAPTER 1~
Statement of Inquiry:
8/26/2015
AGENDA
5 min
~HOMEOSTASIS
WARM-UP RECALL TO CHAPTER 1~
What are the two homeostatic mechanism that occur in the body?
Give a physiological example of each mechanism. Include the stimulus, receptor, control center, effector for each.
Objective: SWBAT investigate and explain homeostasis and the transportation of molecules, across membranes.
Enter the classroom silently and find your seat.
Essentials: Pen or Pencil, book, Cornell notes page.
HW: Scientific Method in Action
Warm - Up
Wait silently for instructions

2. Objective:
By the end of the class scholars will be able to understand the homeostatic mechanism of the human body involved with positive and negative feedback.
What do you remember from chapter 1?
Shout out.

3. Homeostasis
Maintaining a healthy environment inside the body with the organs working together to control factors within normal boundaries such as:
body temperature
blood pressure
blood sugar
water balance
sodium levels

4. Control Center Effector
Stimulus
Afferent pathway
Change in variable
Receptor
Structure that detects change in variable
Efferent pathway
Control Center
Initiates change based on input from receptor
Effector
Structure that causes change to stimulus
Homeostasis
Internal balance returned

5. Negative Feedback
Conditions exceeding a set limit in one direction triggers a reaction in the opposite direction

6. Example of Negative Feedback
Body temperature rises above normal temperature
Body receptors detect change in temperature
Hypothalamus in the brain trigger signals to different organs
Human body starts sweating
Evaporation of sweat on the skin cools the body
Blood vessels close to the skin dilate to help release heat
Write an example of a negative feedback loop if the body became too cold. Include stimulus, receptors, control center, effectors.

7. Positive Feedback
Conditions exceeding a set limit in one direction trigger a reaction in the same direction

8. Homeostatic Imbalance
Organ systems have a diminished ability to keep the body’s internal environment in a certain range
Example: type II diabetes
Insulin controls blood sugar levels and moves glucose out of bloodstream
Pancreas does not make enough insulin or cells do not respond normally to insulin
Could lead to kidney failure, limb amputations, blindness

9. Metabolism Metabolism = all chemical operations within the body
Anabolism = complex proteins constructed from simpler proteins
Catabolism = complex proteins broken down into simpler proteins
ATP from food we eat

10. Areas to review for the test
Body regions
Relative directions
Body cavities
Characteristics of life
Cell organelles – function
Cell cycle – cancer, stem cells
Homeostasis/metabolism
Active & passive transport
Osmosis
SPELLING COUNTS!

11. Exit Ticket
1. All chemical operations going on within the body are collectively known as: A. Metabolism B. Homeostasis C. Syndrome D. Pathology 2. Which body systems typically initiate homeostatic responses? 3. In breast feeding, the harder and more frequent the infant suckles, the more milk is produced and secreted from the mammary glands and ducts. This phenomenon is called: A. Metabolism B. Anabolism C. Negative feedback D. Positive feedback 4. Describe what homeostasis is and how it helps to maintain health.