Chapter 1 Flashcards
Anatomy
- To “cut up” or dissect
- Study of internal and external structures
- Study of relationship among body parts
Physiology
Study of how living organisms perform the functions essential to life
All ______ are performed by ______
• 2 examples
- specific functions; specific structures
* red blood cells and thick and thin filaments
Levels of organization (6)
- Chemical level
- Cellular level
- Tissue level
- Organ level
- Organ system level
- Organism level
Chemical level
Atoms combine to form molecules
Cellular level
Molecules work together to form structural and functional components of cells
Tissue level
Groups of cells working together to perform 1 or more specific functions
Organ level
2 or more tissues working together to perform 1 or more specific functions
Organ system level
• definition
• example
Multiple organs working together
• Heart + blood + blood vessels
Organism level
Highest level of organization
Homeostasis
The existence of a stable internal environment
Homeostatic regulation
Adjustment of physiological systems to preserve homeostasis
What happens if homeostasis is not maintained?
Results in illness/death
Three components to homeostasis
- receptor
- control center
- effector
Receptor
•what does it do
•what does it sense
• what does it receive
- serves as a sensor
- Senses environmental change = stimulus
- receives stimulus
Negative feedback •what happens •does activity oppose or enhance stimulus • common or uncommon • example
- variations trigger a response to correct the problem
- activity tends to oppose the stimulus
- most common type
- regulatory control
- thermoregulation
Positive feedback •what happens • does activity oppose of enhance stimulus • common or uncommon • 2 example
- stimulus produces a response that increases change
- enhance stimulus
- Does not really occur because response takes body away from homeostasis
- milk-let down reflex, blood clotting
Milk-let down reflex
•5 steps
- Receptor: receptors in nipples stimulated
- Impulses propagated to spinal cord
- Control center: stimulation of hypothalamic nuclei
- Oxytocin released
- Effector: milk is ejected
