Anatomy Chapter 13

Respiratory System

Lung Cancer

This form of cancer is most often malignant meaning that the cancer spreads and invades the healthy tissue around them and throughout the body. It is very dangerous and deadly.

Smoking

80% of lung cancer deaths are due to this preventable cause. Even being near someone who smokes can put you at risk. THis is the most influential cause of lung cancer as smoking overwhelms the mucus and cilia defenses of the lungs and they become nonfunctional. There are 200 carcinogens in tobacco smoke.

Vaping

This is another cause of damage to the body and the lungs but more research is underway. E-cigarettes cause impaired blood vessel and heart functions due to oxidative stress, contains toxic aldehydes, has trace metals linked to cancer, contain nicotine that can lead to cancer, impairs vasodilation, increase arterial stiffness, increase blood pressure, increase blood pressure, suppress cough reflexes, inhibits alveolar macrophage function, causes inflammation, and causes an inhibition of phagocytosis.

Cardiovascular System

Functions to transport respiratory gases throughout the body and to tissues. It is responsible for gas transport and internal respiration.

Respiratory System

Functions to change gases exchange gases between the blood and the atmosphere by inhaling and exhaling atmospheric gases.

Law of Diffusion

Gases move from areas of high concentration to low concentration.

External Respiration

The gas exchange that occurs within the lungs and is the major function of the respiratory system. Oxygen is inspired and diffuses into the blood and Carbon Dioxide is expired. The exact location is the alveolar capillaries within the lungs.

Carbon Dioxide Transport

Transported as 70% bicarbonate ion, 20% bound to hemoglobin at the globin protein, 7% dissolved in plasma.

Oxygen Transport

Transported bound to hemoglobin by iron.

Internal Respiration

The exchange of gases between blood and deep tissues. Blood arriving to the tissue capillaries diffuses into oxygen poor tissue and CO2 moves into the blood and back to the lungs to be expelled.

Pharynx

Throat-air travels through here to get to the lungs.

Larynx

The voicebox. Vibrations of the vocal folds in this structure allows us to speak.

Epiglottis

This cartilaginous structure covers the larynx when we swallow so only air can enter it.

Trachea

Air travels through this structure with cartilage rings before branching into the bronchi. It is lined with cilia.

Bronchus

The trachea branches into these ringed structured rings that transport air deeper into the lungs

Cartilaginous Rings

These help prevent respiratory passages from collapsing when there is low pressure.

Bronchioles

The smallest respiratory passageways

Alveoli

These small structures are the site of external respiration. They are small clusters at the end of bronchioles covered in pulmonary capillary beds. THey are only one cell layer thick allowing for easy gas diffusion.

Nasal Cavity

AIr enters here and it has veins, mucus, and cilia to aid in purifying, moistening, and warming up the air.

Tonsils and Adenoids

Lymphatic organs that function to purify air entering the oral and nasal cavity.

Purify Air

This function is carried out by mucus and cilia in the nasal cavity and trachea as well as by tonsils and adenoids.

Moisten Air

THis function is carried out by mucus that prevents the respiratory passageways from drying out.

Warming AIr

Thin walled veins in the naval cavity work to perform this function.

Inspiration

Air flow into the lungs

Inhale

When the diaphragm and external intercostals contract expanding the thoracic cavity and allowing for air to move into the lungs.

Air flows into the lungs

According to the laws of diffusion, if the volume of the lungs expand and the pressure drops will air flow into or out of the lungs?

Expiration

Air flow out of the lungs

Exhale

The diaphragm and external intercostals relax and curve upwards into the thoracic cavity. This is a passive process as the muscles are relaxing.

Air flows out of lungs

According to the laws of gas diffusion if the lungs shrink in volume and their is a higher gas pressure will air flow into or out of the lungs?

Asthma, Bronchitis, Pneumonia

These conditions can cause exhaling to become harder, more laborious, and an active process as the internal intercostals and abdominal muscles are needed to aid in pushing air out of the lungs.

Medulla and Pons

Neural centers that control respiratory rhythm and depth of breathing. Regular respiratory rate us about 12-15 respirations per minute.

Carbon Dioxide

High levels of this gas acts as a stimuli for the medulla to increase the rate and depth of breathing

Exercise

This action causes our brain to send more impulses to our respiratory muscles us causing us to breathe more deeply and quickly. Other physical factors like talking, coughing, and increased body temperature have an influence on our rate of breathing.

Death

When the medulla center is completely suppressed with an overdose of pills, morphine, or alcohol this occurs.

Conscious Control

This is a short term process and has limitations. After longer periods of time involuntary controls take over to regulate normal respiration.

Emotional Factors

Factors like anxiety, stress, or fear can stimulate change to respiratory rate.

Hiccups

Involuntary spasms of the diaphragm. The sound comes from inspired air hitting the vocal folds of the closed glottis.

Coughing

Irritation or overaccumulation of mucus that causes air to be forced superiorly from the lungs against the glottis and through the oral passageway which helps clear the lower respiratory passageways.

Sneezing

Similar to a cough except that expelled air is directed through nasal cavities instead of through the oral cavity. These help to clear the upper respiratory passageways.

Yawning

Very deep inspiration that ventilates all alveoli. Many hypotheses exist as to why this occurs.

Choking

When the airways are clocked (usually by a large object in the trachea or the primary bronchi). The heimlich maneuver can be performed to attempt to dislodge the object as air is forced out of the lungs.

Hyperventilation

Brought on by stress or anxiety and causes breathing to become very rapid and deep. It leads to a dramatic decrease in carbon dioxide levels in the blood. It is a from of positive feedback and may continue to accelerate if not controlled. Breathing into a bag can help because you breath in more CO2 and can bring blood levels back to normal.

Chronic Obtrusive Pulmonary DIseases (COPD)

Consists of chronic bronchitis and emphysema.

Chronic Bronchitis

Inflammation of the bronchioles resulting in excessive mucus production, chronic cough, and bronchospasms.

Emphysema

Destruction of alveolar walls and chronic inflammation causes lungs to become less elastic, and this causes collapse of the airways and trapping of air. Exhaling requires incredible amounts of energy and leads to exhaustion from breathing.

Asthma

A condition that causes inflammation and spasms of the bronchioles, which makes breathing very difficult. It can be triggered by allergens, cold weather, exercise, etc. Inhalers which contain bronchodilating chemicals that open the airways and reduce spasms often work for patients for short-term emergency relief.

Cystic Fibrosis

The most common fatal genetic disease in the U.S. Roughly two children die of this every day in the U.S. This causes oversecretion of a thick mucus that clogs respiratory passageways and puts the child at risk for fatal respiratory infections.

Sudden Infant Death Syndrome (SIDS)

When health infants stop breathing and die in their sleep. Believed to be caused by abnormal neural control of respiration and heart rhythm abnormailty.

Carbon Monoxide Poisoning

CO is a colorless odorless gas that displaces oxygen at binding sites at the hemoglobin. It kills the victim quietly as the victim becomes confused, has a throbbing headache, and/or falls asleep leading to a silent death. Victims can be given 100% oxygen to prevent death and clear out CO.

Apnea

Cessation of breathing. Sleep apnea is the stopping of breathing while breathing. Victims often don’t know they have this condition while sleeping but wake up exhausted and restless because their bodies are constantly woken throughout the night.