Organ System Overview
1. Integumentary
Forms the external body covering, protects deeper tissue from injury, synthesizes
vitamin D, location of cutaneous nerve receptors
2. Skeletal
Protects and supports body organs, provides muscle attachment for movement,
site of blood cell formation, stores minerals
3. Muscular
Allows locomotion, maintains posture, produces heat
4. Nervous
Fast- acting control system, responds to internal and external changes (stimuli),
activated muscles and glands, helps to regulate body temperature, maintains
homeostasis
5. Endocrine
Slow-acting control system, secretes regulatory hormones for growth,
reproduction and metabolism through the use of hormones released in the blood,
maintains homeostasis
6. Cariovascular
Transports materials in the body via blood pumped by the heart, like oxygen,
carbon dioxide, nutrients, plasma and wastes
7. Lympatic
Returns fluids to blood vessels, disposes of debris, involved in immunity, houses
white blood cells
8. Respiratory
Keeps blood supplied with oxygen, removes carbon dioxide, gas exchange
between blood and tissue happens in capillary bed
Smallest vein- venule, smallest artery- arteriole
9. Digestive
Breaks food down, allows for nutrient absorption into blood, eliminates
indigestible material (what we don’t absorb from the food goes out of the body)
10. Urinary
Eliminates nitrogenous waste, maintains acid-base balance, regulates water and
electrolytes
11. Reproductive
Production of offspring
Necessary Life Function
1. Maintaining boundaries- each living thing must be able to keep what’s inside
separate from what is outside. Cells maintain boundaries by having a plasma
membrane. The integumentary system protects the internal organs from drying
out, heat, bacteria sunlight and other chemicals.
2. Movement- locomotion, movement of substances (nutrients- by blood vessels,
wastes by dietary tract)
3. Responsiveness- ability to sense changes and react (nervous system)
4. Digestion- break down and delivery of nutrients
5. Metabolism- refers to all the chemical reactions in the body, breaking down
substances and building substances (synthesizing) production of energy, making
body structures
6. Excretion- elimination of waste from metabolic reactions
7. Reproduction- production of future generation
8. Growth- increasing of cell size and more often growth is by increasing the
number of cells. For growth to occur, cell construction must occur faster than cell
destruction.
Survival Needs
1. Nutrients- chemicals for energy and cell building. Includes carbohydrates,
proteins, lipids, vitamins and minerals.
2. Oxygen- required for chemical reactions. Most of energy produced in the body
uses oxygen. **MOST IMPORTANT SURVIVAL NEED**
3. Water- 60-80% of body weight, most abundant chemical substance in body.
Provides the fluid base for body secretions and excretions. Provides for metabolic
reaction.
4. Stable body temperature- chemical reactions are affected (refers to metabolism)
5. Atmospheric pressure- must be stable. This is the force exerted on the surface of
the body by the weight of the air. The function of breathing depends upon the
appropriate atmospheric pressure.
**HOMEOSTASIS**
Describes the body’s ability to maintain a relatively stable internal environment even
though the world outside the body is changing. We have to maintain a dynamic state of
equilibrium inside the body. We have 2 systems that help in maintaining homeostasisNervous and Endocrine