Respiratory System Structure/Function
Describe the major functions of the respiratory system.
1. Supply body with O2 for cellular respiration
2. Dispose of CO2 through ventilation
3. Olfaction (smell) and speech (resonance)
The treatment for tracheal obstruction is....
Define the following:
Patm:
Ppul:
Pip:
Patm: atmospheric pressure; pressure exerted by air surrounding the body
Ppul: intrapulmonary pressure; pressure in the alveoli that fluctuates with breathing
Pip: intrapleural pressure; pressure in the pleural cavity that fluctuates with breathing! should always be negative (gun shot, stabbing, or rib puncture could affect this pressure)
Bolus is chewed and moistened food that is being send to the stomach and intestines for digestion. It can be found in the mouth, pharynx, and esophagus.
Chyme is a more liquid substance that consists of bolus that is mixed with gastric juices. Chyme can be found in the stomach and small intestine.
What condition is caused by decreased salivary production and gland function?
What is the difference between internal respiration and external respiration?
Internal respiration = gas exchange between the blood and the body tissues
External respiration = gas exchange between the blood and the lungs
Infected and swollen ______ can block air passage in the nasopharynx, making it necessary to breathe through the mouth. Why is this an issue?
Adenoids
This is an issue because air is not properly moistened, warmed, or filtered before reaching the lungs when you breathe through your mouth only. Swollen adenoids may also impact sleep (sleep apnea) and speech.
What type of breathing pattern is the most effective in regard to alveolar ventilation: normal rate and depth, slow deep breathing, or rapid shallow breathing?
Slow deep breathing is most effective (85%).
*rapid, shallow breathing is LEAST effective*
Describe the importance of the salivary glands in the digestive system.
Cleanses mouth, dissolves food chemicals for taste, moistens food and compacts into bolus, starch breakdown by salivary amylase
Stomach acid regurgitating into the esophagus causes _________.
heartburn
*GERD is a condition characterized by chronic heartburn and indigestion
Name the two zones of the respiratory system and describe the major role of each zone.
1. Conducting zone - PATHWAYS; transport gases to and from gas exchange sites, cleanses, warms, and humidifies air
2. Respiratory zone - site of gas exchange
What is smoker's cough and what structures does it affect?
a condition in which cilia in the respiratory tract are destroyed by smoking and become unable to clear mucus that accumulates in the lungs, resulting in coughing
What are the two inward forces acting on the thoracic cavity that promote lung collapse?
1. lung elasticity (gives lungs a natural tendency to recoil)
2. alveolar surface tension (pulls on alveoli to reduce alveolar size)
*OUTWARD FORCE (tends to enlarge lungs) = elasticity of chest wall
Describe the phases of digestion that occur starting from the mouth and ending at the stomach.
1. Buccal phase: tongue forces bolus into oropharynx
2. pharyngeal-esophageal phase: tongue blocks mouth while uvula blocks the nasopharynx while eppiglottis blocks trachea; constrictor muscles of pharyngs force food into the esophagus
3. Peristalsis: moves food through esophagus and down to the stomach
4. Gastroesophageal sphincter opens: allows food to enter the stomach; closes after food enters to prevent regurgitation
If a foreign body, pathogen, or irritant breaches the stomach's mucosal barrier, what would result?
Gastritis: inflammation of the stomach lining that causes abdominal pain, nausea, vomiting, and a feeling of fullness in the upper abdomen
In fibers that innervate the lungs, parasympathetic fibers cause ________, where as sympathetic fibers cause _______.
bronchoconstriction; bronchodilation
Parasympathetic = rest and digest. When you are relaxed, you don't need to be inhaling and exhaling a whole lot of oxygen, so your bronchioles constrict to slow airflow into and out of the lungs.
Sympathetic = fight or flight. When this nervous system is activated you want as much oxygen to get to the tissues as possible to create energy
What is pneumothorax and how is it typically treated? What other condition can it lead to?
Pneumothorax is air in the pleural cavity, and it is treated by removing air with chest tubes. This can lead to atelectasis (lung collapse).
Describe the effect alveolar Pco2 has on the lower respiratory structures.
Where alveolar CO2 is high, bronchioles dilate to eliminate CO2 more rapidly. Where alveolar CO2 is low, bronchioles constrict to try to balance out the pressures of each gas.
What are the three phases of nervous system regulation of the GI tract? What stimulates/inhibits each phase?
1. Cephalic/reflex phase: short duration before ingesting food that triggers the vagus nerve. Stimulated by sight, smells, taste, or thought of food. Inhibited by loss of appetite.
2. Gastric phase: 3-4 hour stage where food is in the stomach. Stimulated by stomach distension, gastrin release, and chemical stimuli. Inhibited by high acidity in the stomach.
3. Intestinal phase: food is in the intestines being digested and absorbed. Stimulated by distension of intestines (chyme in the intestines). Inhibited by overdistension or irritation.
Name one common malabsorption disease and its treatment.
What three physical factors influence the ease of air passage, and the amount of energy required for ventilation? Briefly describe each factor.
1. Airway resistance: increased friction reduces gas flow
2. Alveolar surface tension: attraction of liquid molecules to one another; tends to shrink/collapse alveoli, making it harder to breathe. Surfactant is the fluid that combats this surface tension by allowing the alveoli to expand, making it easier to breathe.
3. Lung compliance: how much "stretch" the lung has
How does the deficiency of surfactant in the lungs contribute to the pathophysiology of infant respiratory distress syndrome? What medical interventions can help treat this condition?
Decreased surfactant increases alveolar surface tension, which results in the collapse of alveoli after each breath. IRDS is treated by spraying natural or synthetic surfactant into newborn's airways. It can also be treated with positive pressure devices to inflate alveoli.
Describe (in detail) the sequence of events involved in inspiration and expiration. Be sure to include the structures involved, volume or pressure changes that occur, and the direction of air flow.
INSPIRATION:
diaphragm and intercostals contract, thoracic cavity volume increases, intrapulmonary volume increases, intrapulmonary pressure decreases, air flows into lungs
EXPIRATION:
diaphragm and intercostals relax, thoracic cavity volume decreases, elastic lungs recoil passively, intrapulmonary volume decreases, intrapulmonary pressure increases, air flows out of lungs
Describe the major functions of each of the following accessory digestive organs:
Liver
Gallbladder
Pancreas
Liver: production of bile and storage of some fat-soluble vitamins
Gallbladder: stores bile
Pancreas: supplies enzymes needed to digest chyme and bicarbonate to neutralize stomach acid
What is the importance of bacteria in the large intestine? What bacteria is the most common cause of antibiotic-associated diarrhea?
Bacteria in the large intestine aid in crucial metabolic processes such as fermentation of indigestible carbohydrates for energy and vitamin B (and sometimes K) synthesis. We generally have more good/helpful bacteria in our bodies than bad.
Clostridium difficile is the most common cause of antibiotic-associated diarrhea. This bacteria is antibiotic resistant. Good bacteria are killed by antibiotics, giving C. difficile more room to proliferate and flourish.