1. Part 1: An Overview Part 2: Maintaining Homeostasis
ANATOMY & PHYSIOLOGY
Part 1: An Overview
Part 2: Maintaining Homeostasis

2. Anatomy & PHYSIOLOGY Anatomy = STRUCTURE Physiology = FUNCTION
What does it look like?
What is it made of?
Physiology = FUNCTION
What does it do?
The structure of a body part is directly related to its function!

3. Levels of organization
*Each level of the body is connected to the next level… Starting with the chemical level which includes:

4. Levels of organization
Atoms  Molecules

5. Levels of organization
Organelles  Cells

6. Levels of organization
Tissues  Organs

7. Levels of organization
Organ systems  Organism

8. All organ systems are interconnected!

9. Homeostasis defined: The body’s ability to maintain
a relatively stable
internal environment

10. Homeostatic control mechanisms
Receptor: senses stimuli and sends info (input) to control center
Control center: determines the set point; analyzes info and determines the appropriate response
Effector: carries out the response (output)
Efferent pathway provides feedback  positive or negative

11. Homeostasis can be controlled in 2 ways:
1) NEGATIVE feedback mechanism
Most common
Occurs when a pathway regulates itself by shutting off (inhibiting) the beginning of the pathway
* Reverses original stimulus
Ex: fever

13. Homeostasis can be controlled in 2 ways:
2) POSITIVE feedback mechanism
Occurs when the original stimulus is increased
Ex: labor (childbirth)

15. DISEASES/DISORDERS
Acute: affects a person for a certain amount of time; usually temporary
Ex: heart attack
Chronic: remain for a long time and can get worse; usually no cure
Ex: atherosclerosis (heart disease)

16. Diseases vs. disorders
Both = disruption of homeostasis Disease: illness characterized by a particular set of signs and symptoms Disorder: abnormality of function

17. Signs vs. symptoms
Symptom: subjective change in body function Sign: measureable condition

18. Examples
Ex of SIGN: nausea, headache
Ex: fever, rash, diarrhea