From American bison to rhinoceros and over Very fast, similar to modern whales ; but about half that of a scaled-up altricial bird one that is born helpless — if one could scale up a bird to 25, kilograms 25 long tons; 28 short tons Whales A graph showing the hypothesized growth curves body mass versus age of four tyrannosaurids. Tyrannosaurus rex is drawn in black. Based on Erickson et al.
A deeper look into the anatomy and the physiological mechanisms of the human lungs requires using the knowledge gained from research, lab and coursework of the respiratory system.
The respiratory system begins with respiratory airways that lead into the lungs. These airways include nasal passages, pharynx, trachea, larynx, right and left bronchi, bronchioles and clusters of alveoli.
The lungs themselves occupy most of the thoracic cavity and each lung is divided into several lobes. The diaphragm and pleural sac are important components to the respiratory system as well.
The pleural sac is a thin layer of tissue covering the lungs and the wall of the chest cavity to protect and cushion the lungs. The diaphragm is a sheet of skeletal muscle that lies inferior to the lungs. When this sheet of muscle contracts, air is pulled into the lungs and when the muscle relaxes air is pushed out of the lungs.
Alternate contractions and relaxations of the diaphragm and other inspiratory muscles indirectly produce inflation and deflation.
Breathing is mechanically accomplished by alternately shifting the direction of the pressure gradient for airflow between the atmosphere and alveoli through the cyclic expansion and recoil of the lungs.
Changes in intra-alveolar pressure produce flow of air into and out of the lungs. If this pressure is less than atmospheric pressure, air enters the lungs. If the opposite occurs, air exits from the lungs Sherwood ; Sherwood The air and blood undergo a gas exchange which occurs in these alveolar air sacs.
This occurs through the capillary network around each alveolus, a gas exchange occurs where carbon dioxide is released into the alveolar sacs and into the air LabTutor Basically, the body takes in oxygen and expels carbon dioxide.
Through the process of breathing, a technique known as spirometry can be performed in order to record respiratory variables. Asthma is a condition in which the airway occasionally constricts, becomes inflamed, and is lined with excessive amounts of mucus, often in response to one or more triggers Taylor Pulmonary fibrosis is a chronic progressive interstitial lung disease of unknown etiology Sherwood ; Sherwood COPD is the 12th leading cause of death in the world, and the 5th leading cause of death in Western countries LabTutor There are many different lung capacities and volumes that should be taken into consideration when using spirometry.
Forced vital capacity FVC is the total amount of air that can forcibly be blown out after full inspiration, measured in liters.
Vital capacity VC is the maximum amount of air that can be expelled in a single breath following FVC. Forced expiratory volume in one second FEV1 is the amount of air that you can forcibly blow out in one second, measured in liters.This is a review of the psychological field of psychoneuroimmunology (PNI) and how psychopathology has an impact on the immune system.
Two areas of study of PNI are examined: first, how the psychosocial environment affects the health of an individual along with the impact stressors play on the.
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Respiratory System Research. The respiratory system consists of the lungs, airways, diaphragm, trachea (windpipe) and pharynx (throat) and its primary function is the exchange of oxygen and carbon dioxide- breathing in and out.
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