Transcript Guided Notes for the Control of Respiration

Guided Notes for the Control
of Respiration
1. The activity of the respiratory
muscles, the diaphragm and
external intercostals, is regulated
by nerve impulses transmitted to
them from the brain by the
phrenic and intercostal nerves.
2. The medulla oblongata sets the
basic rhythm of breathing.
Impulses from the pons and
medulla maintain a rate of 12 to
15 respirations per minute. This
normal rate is called eupnea.
3. During exercise, the brain
centers send more impulses to
the respiratory muscles. This
pattern is called hypernea.
4 Factors That Affect the Rate and
Depth of Respiration
1.
2.
3.
4.
Talking
Coughing
Exercise
Increased body temperature
5. Voluntary control of breathing is
limited, and our respiratory
centers will simply ignore
messages from the cortex when
oxygen supply in the blood is too
low or blood pH is falling.
6. The most important factors that
modify respiratory rate and depth
are chemical—the levels of
carbon dioxide and oxygen in the
blood.
7. Although every cell in the body
must have oxygen to live, it is
the body’s need to rid itself of
carbon dioxide (not take in
oxygen) that is the most
important stimulus for breathing
in a healthy person.
8. What is the purpose of
hyperventilation?
It blows off more carbon dioxide
and decreases the amount of
carbonic acid in the blood,
returning its pH to normal levels.
Name the 4 features common to
COPD’s
1. Patients almost always have a
history of smoking
2. Dyspnea—difficult or labored
breathing
3. Coughing and frequent pulmonary
infections
4. Most COPD patients are hypoxic,
retain carbon dioxide, and have
respiratory acidosis
10. In emphysema, the alveoli enlarge
as the walls of adjacent chambers
break through, and chronic
inflammation promotes fibrosis of the
lungs. Emphysema patients use an
incredible amount of energy to
exhale, and they are always
exhausted.
11. In chronic bronchitis, the mucosa of
the lower respiratory passages
becomes inflamed and produces
excessive amounts of mucus. The
pooled mucus impairs ventilation and
gas exchange and dramatically
increases the risk of lung infections.
12. Cystic fibrosis, which is the most
common lethal genetic disease in the
U.S, causes oversecretion of a thick
mucus that clogs the respiratory
passages and puts the child at risk for
fatal respiratory infections.
13. Asthma is caused by
chronically inflamed,
hypersensitive bronchial
passages that respond to many
irritants with dyspnea, coughing,
and wheezing.