6. - Is also a part of the respiratory
system.You inhale the air that carries the
odor of an object through your nose.
- The nose is divided into external part and
internal part
7. External Part
• The external part is your nose . Your nose is
made up of bone and cartilage. They shape to
your nose.
• Odors of object are carried by the air to your
nose . When you breathe , the odors enter the
two openings of your nose called nostrils.
Nostrils serve as entrance to your nasal cavity.
8. Internal Part
• The interior part of the nose is divided into
two major passages called nostrils. Each
nostril has the respiratory region, which is
used for breathing; and the olfactory region ,
which is used for smelling.
9. Internal Part
• The nasal cavities are lined with small, hairlike
structures called cilia. These cavities also
contain mucous membranes that secrete a
sticky fluid called mucus. As you inhale , air
that enters the nose is filtered by the cilia,
moistened by the mucus , and warmed by the
blood within the blood vessels.
10. Internal Part
• The olfactory region, which is located within
the mucous membrane , contains olfactory
cells. These are the nerve cells sensitive to
odor. Stimulation of these cells by the odor
from the environment results in the sensation
of smell. The odor carried by the air stimulate
the nerve cells.The messages are then carried
by the nerve cells to the brain where they are
interpreted.
11. Smelling too long
• Even if you are several meters away from the
poultry farm you can already smell the bad
odor of chicken manure, so you cover your
nose with a handkerchief. Notice that poultry
ma n does not cover his nose. He cannot smell
the bad odor anymore because ha has gotten
used to it. The olfactory nerve cells of his nose
become less sensitive to the bad odor of the
chicken manure because of long exposure to
it.
12. Common Nose Ailments
• Nosebleed – usually caused by an injury to any
part inside the nose, head injury , high blood
pressure , or weak blood vessels in the nose.
Infections and blood disorders can also cause
nosebleed.
13. Proper Care for the Nose
1. Cover your nose if you are in the dusty or
stinky area.
2. Keep your nose clean. Use clean and soft
cloth to clean it.
3. Avoid blowing your nose hard when you have
colds to prevent nose bleeding.
14. Proper care for the Nose
4. Avoid putting any of your fingers or any
pointed object inside your nose.
5. Stay away from smoky places.
15.
16. Sense of Smell of the snake
A snake flick outs its tongue to pick up the tiny
particles left by animas such as mice and
birds. The particles may be in the air , along
the ground , or on a surface such as a tree
trunk. When the snake brings its tongue back
inside its mouth, the particles enter a special
part in the roof of its mouth. This particles
identifies the smell , and the snake can track
down its food.