Human Body Study Guide
Locomotion, necessary to escape danger, obtain food and shelter,
and reproduce, is accomplished by the interaction of the skeletal
and muscular systems, and coordinated by the nervous system.
Functions of the Skeletal System:
The digestive system consists of organs that are responsible for the
mechanical and chemical breakdown of food. The breakdown process
results in molecules that can be absorbed and transported to cells.
mechanical digestion: The physical breakdown of
1. provides shape & structure
food into smaller pieces.
2. enables you to move
3. produces blood cells
mouth: teeth break food into pieces
esophagus: forms food into a ball
stomach: churns food into a liquid
4. protects organs
chemical digestion: The use of acids and enzymes to
change the food into nutrient molecules.
5. stores minerals and other materials
mouth: adds saliva to begin digestion
stomach: adds acid and enzymes (pepsin)
small intestine: adds bile and pancreatic enzymes
large intestine: bacteria work on indigestible material
The circulatory system moves substances to and from cells,
where they are needed or produced, responding to changing
demands.
Absorption is the process by which nutrient molecules are
taken into (absorbed) into the blood stream to be delivered
to the cells of the body.
The circulatory works with many systems:
digestive:
blood collect digested nutrients and
delivers them to body cells
respiratory:
the blood collects and delivers needed
oxygen and carries waste to be removed by the lungs
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Arteries carry blood away from the heart.
Veins carry blood toward the heart.
Capillaries allow for the exchange of needed
materials between the blood and body cells.
Diffusion occurs in the capillaries. It is when
molecules travel from an area if high concentration
to an area of lower concentration. This is how the
exchange of oxygen and nutrients happen.
During respiration, cells use oxygen to release the energy
stored in food. The respiratory system supplies oxygen and
removes carbon dioxide (gas exchange).