Levels of Structural Organization of the Human Body:
1. Atoms- tiny building blocks of matter
2. molecules-lots of atoms
3. organelles-basic components of microscopic cells
4. cells-smallest units of living things
5. tissue-groupings of similar cells with common function (epithelium, connective tissue, nervous tissue and muscle) 6. organs-discrete structure composed of at least two tissue types that performs a specific function in the body 7. organ system-organs work together to accomplish a common purpose 8. organism-living being
Functional Characteristics to maintain Life:
1. Maintaining boundaries: internal environment must be separate from the external environment 2. Movement
3. Responsiveness: (or excitability) the ability to sense changes in the environment and then respond to them. 4. Digestion: the breaking down of food to simple molecules that can be absorbed into the blood 5. Metabolism: all chemical reactions that occur within body cells 6. Excretion: removing waste
7. Reproduction: cellular level for body growth or repair, or reproduction of whole new person 8. Growth: increase in size
11 organ systems of the Body (pg 60)
4. Normal body temp.
5. Appropriate atmospheric pressure
Homeostasis: bodies ability to maintain relatively stable internal conditions even though the outside world changes continually. (unchanging) a dynamic state of equilibrium or balance, Negative Feedback: the output shuts off the original effect of the stimulus or reduces its intensity. (Heater in a house) opposite direction of initial change. Keeps body chemicals or functions within a narrow range. Positive Feedback: result enhances...