Other diseases caused by Streptococci:. Corynebacterium diphtheriae. Bacterial causes of the common cold: Mycoplasma pneumoniae, Coxiella burnetii. Remember that most colds are viral. See Chapter 10 on these groups of viruses. Common Cold - clinical signs: sneezing, rhinorrhea excess nasal mucous , nasal congestion, sore throat, fever, headache; malaise feeling of general discomfort due to interferons produced to combat the infection; cold typically lasts 1 week; transmission mainly by direct contact hand to hand or fomites; also by respiratory droplets; treatment: none - recovery depends on individual's immune system - antibiotics are useless; over-the-counter medications only help alleviate symptoms.
Coronaviruses - also cause the common cold. Other viral causes of the common cold: coxsackieviruses, echoviruses, adenoviruses, myxoviruses. Streptococcus pneumoniae [pneumococcus]. Pneumococcal Pneumonia. Mycoplasma pneumoniae. Chlamydia psittaci. Ornithosis, Psittacosis, or Parrot Fever.
Coxiella burnetii. Q Fever. Legionella pneumophila. Legionellosis or Legionnaires' disease. Bordetella pertussis. Pertussis Whooping Cough. Mycobacterium tuberculosis. Skin testing. Important: The number of cases in the U. New drug-resistant strains have been identified; have emerged in patients who did not finish their full course of medication and are lost to medical follow-up.
Influenza virus. Influenza Flu. Parainfluenza virus. Which of the below tissues provides the functions of the inner layer of the conducting organs? The point where the trachea divides into right and left primary bronchi is a ridge called Carina Secondary bronchioles Parietal pleura Visceral pleura Diaphragm. Which of the below tissues forms the exchange surfaces of the alveolus?
These are cells of the alveoli that produce surfactant. This is direction of diffusion of gases at capillaries near systemic cells. Oxygen into blood , Carbon dioxide into blood Oxygen out of blood , Carbon dioxide into blood Oxygen into blood , Carbon dioxide out of blood Oxygen out of blood , Carbon dioxide out of blood. This is direction of diffusion of gases at the alveoli of the lungs. This means the lungs and the chest wall expand easily. High surface tension Low surface tension High compliance Low compliance None of the above.
The conducting airways with the air that does not undergo respiratory exchange are known as the Inspiratory volume Expiratory reserve volume Minimal volume Residual volume Respiratory dead space. This is the sum of the residual and the expiratory reserve volume.
Total lung capacity Functional residual capacity Inspiratory capacity Vital capacity Minimal volume. Partial pressure difference of the gases Surface area for gas exchange Diffusion distance Molecular weight and solubility of the gases Force of contraction of diaphragm.
Which is the dominant method of carbon dioxide transport? Bound to hemoglobin Bound to oxygen Dissolved in plasma as a gas Dissolved in plasma as bicarbonate ions Diffusion. Where are the nasal conchae? This portion of the pharynx has five openings in its wall. Which tonsils are found in the oropharynx? Where is the larynx? This is a ring of hyaline cartilage that forms the inferior wall of the larynx.
Where is the uvula? Where are the palatine tonsils? E F R U None of the above. Where is the soft palate? Where is the epiglottis? The principal muscle of respiration in the human body is the diaphragm, a thin sheet of skeletal muscle that forms the floor of the thorax. When the diaphragm contracts, it moves inferiorly a few inches into the abdominal cavity, expanding the space within the thoracic cavity and pulling air into the lungs.
Relaxation of the diaphragm allows air to flow back out the lungs during exhalation. Between the ribs are many small intercostal muscles that assist the diaphragm with expanding and compressing the lungs. These muscles are divided into 2 groups: the internal intercostal muscles and the external intercostal muscles. The internal intercostal muscles are the deeper set of muscles and depress the ribs to compress the thoracic cavity and force air to be exhaled from the lungs.
The external intercostals are found superficial to the internal intercostals and function to elevate the ribs, expanding the volume of the thoracic cavity and causing air to be inhaled into the lungs.
Pulmonary ventilation is the process of moving air into and out of the lungs to facilitate gas exchange. The respiratory system uses both a negative pressure system and the contraction of muscles to achieve pulmonary ventilation. The negative pressure system of the respiratory system involves the establishment of a negative pressure gradient between the alveoli and the external atmosphere.
The pleural membrane seals the lungs and maintains the lungs at a pressure slightly below that of the atmosphere when the lungs are at rest. This results in air following the pressure gradient and passively filling the lungs at rest. As the lungs fill with air, the pressure within the lungs rises until it matches the atmospheric pressure. At this point, more air can be inhaled by the contraction of the diaphragm and the external intercostal muscles, increasing the volume of the thorax and reducing the pressure of the lungs below that of the atmosphere again.
To exhale air, the diaphragm and external intercostal muscles relax while the internal intercostal muscles contract to reduce the volume of the thorax and increase the pressure within the thoracic cavity. The pressure gradient is now reversed, resulting in the exhalation of air until the pressures inside the lungs and outside of the body are equal. At this point, the elastic nature of the lungs causes them to recoil back to their resting volume, restoring the negative pressure gradient present during inhalation.
External respiration is the exchange of gases between the air filling the alveoli and the blood in the capillaries surrounding the walls of the alveoli. Air entering the lungs from the atmosphere has a higher partial pressure of oxygen and a lower partial pressure of carbon dioxide than does the blood in the capillaries.
The difference in partial pressures causes the gases to diffuse passively along their pressure gradients from high to low pressure through the simple squamous epithelium lining of the alveoli. The net result of external respiration is the movement of oxygen from the air into the blood and the movement of carbon dioxide from the blood into the air. Internal respiration is the exchange of gases between the blood in capillaries and the tissues of the body. Capillary blood has a higher partial pressure of oxygen and a lower partial pressure of carbon dioxide than the tissues through which it passes.
The difference in partial pressures leads to the diffusion of gases along their pressure gradients from high to low pressure through the endothelium lining of the capillaries. The net result of internal respiration is the diffusion of oxygen into the tissues and the diffusion of carbon dioxide into the blood.
The 2 major respiratory gases, oxygen and carbon dioxide, are transported through the body in the blood. Blood plasma has the ability to transport some dissolved oxygen and carbon dioxide, but most of the gases transported in the blood are bonded to transport molecules. Hemoglobin can also carry a small amount of carbon dioxide from the tissues back to the lungs.
However, the vast majority of carbon dioxide is carried in the plasma as bicarbonate ion. When the partial pressure of carbon dioxide is high in the tissues, the enzyme carbonic anhydrase catalyzes a reaction between carbon dioxide and water to form carbonic acid. Carbonic acid then dissociates into hydrogen ion and bicarbonate ion.
When the partial pressure of carbon dioxide is low in the lungs, the reactions reverse and carbon dioxide is liberated into the lungs to be exhaled. Under normal resting conditions, the body maintains a quiet breathing rate and depth called eupnea. Autonomic chemoreceptors in the body monitor the partial pressures of oxygen and carbon dioxide in the blood and send signals to the respiratory center of the brain stem. The respiratory center then adjusts the rate and depth of breathing to return the blood to its normal levels of gas partial pressures.
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