9.3 regulation of breathing movements & respiratory disorders
TRANSCRIPT
9.3 Regulation of Breathing Movements
& Respiratory
Disorders
• Breathing is controlled by nerves from the medulla oblongata
Chemoreceptors
Receptors in the body
sensitive to changes in
specific chemicals such as
O2 and CO2.
Alert Medulla to balance
levels using negative
feedback
• CO2 receptors are the main receptors because they are the most sensitive
• If carbonic acid accumulates in the blood it triggers the chemoreceptors.
• The medulla oblongata will send messages to the diaphragm and intercostal muscles
Chemoreceptors
• Oxygen chemoreceptors are found in the carotid and aortic arteries
• Detect low levels of oxygen and send a signal to the medulla oblongata
• Sends messages to the diaphragm and intercostal muscles
Chemoreceptors
Response to Exercise
• Ventilation of alveoli can increase up to 20 times
• 3 factors are important in increased ventilation:– decreased O2
– increased CO2
– increased H+
Accumulation of air inside the chest in
the pleural membrane space due to
puncture of the thoracic cavity.
Causes the lung to
collapse, breathing
becomes difficult to
impossible
Pneumothorax
Smoker’s Cough
• Smoking causes the paralysis and death of cilia = can’t clear debris.
• Also causes the mucus protecting the respiratory system to be less effective.
Pleurisy• Inflammation of the
pleura
• Causes chest pain inhalation issues
• Could cause lungs to collapse and/or suffocation
Bronchitis• Infection caused by bacteria,
viruses or a reaction to one’s environment
• Narrowing of the air passages and inflammation of the mucus lining the bronchial tubes
• VERY serious if it gets into the bronchioles = possible suffocation
Emphysema• Walls of alveoli become inflamed
• Destroys air sacs = less S.A.
• Difficult to exhale, air is trapped in lungs
• Decreased oxygen levels
Pneumonia
• Inflammation of the lungs
• Caused by viruses, molds, bacteria
• Chest pains and fevers
• Can be deadly
Bronchial Asthma• Caused by an allergic reaction
• Walls of the bronchioles become restricted
• Cells secrete abnormally large amounts of mucus
Lung Cancer• Uncontrolled growth of abnormal
cells cause tumors.
• Tumors kill normal cells
The Bends• Under water, with increased pressure, a
diver’s blood and tissues can absorb extra amounts of gases
• If one surfaces too quickly these gases can come out of solution in the blood, cause bubbles
• Diver experiences dizziness, nausea, muscle and joint pain, can be deadly
Pulmonary Tuberculosis • Caused by bacteria
• Very deadly
• Symptoms: – Fatigue– abnormal sounds in the lungs– Fever– Coughing up blood & pus
• Practice Questions
Pg. 297
# 1-4, 7, 8