BODY ORGANIZATION
& HOMEOSTASIS
Chapter 1 Section 1
Pages: 6 - 11
Objectives: Order the levels of organization in the body.
Describe the basic components of a body system &
explain how they work together to function as a system.
The levels of organization in the human body consist of…
1. Cell: the basic unit of structure & function in a living
thing.
Cell Membrane: outside boundary of the cell
Nucleus: control center; directs cell
activities & contains cell information
Cytoplasm: material in a cell; clear, jellylike substance
containing cell structures.
Cell Functions: Carry on processes that keep the
organism alive – Release energy, grow, get rid of waste,
& reproduce.
2. Tissues: A group of similar cells that perform the
same function. The body contains 4 basic types…
*Muscle Tissue: can contract (shorten)
*Nervous Tissue: directs and controls body processes- they
carry electrical messages between the brain and other
body parts.
*Connective Tissue: provides support for your body and
connects all its parts. (bone, blood, and fat for example.
*Epithelial Tissue: covers the surfaces of your body, inside
& out. Skin and the lining of your digestive system are
examples.
3. Organs: A structure that is composed of different
kinds of tissue. An organ performs a complex,
specific job. Examples are: Heart, Brain, Kidneys, etc.
4. Organ Systems: A group of organs that work
together to perform a major function. Examples are:
circulatory system, skeletal system, etc.
Homeostasis: The body’s tendency to keep an internal
balance.
*Homeostasis is the process by which an organism’s
internal environment is kept stable in spite of changes
in the external environment.
Stress: the reaction of your body and mind to potentially
threatening, challenging, or disturbing events.
Adrenaline: Gives you a burst of energy and prepares
your body to take action.
Fight or Flight Response: Reaction from adrenaline. It
prepares you to either fight the stressor OR run away
from the stressor.
Long-Term Stress: Stressor that continue for a long time
Examples:
Short-Term Stress:
Examples:
Dealing with Stress:
Examples: