Mucociliary system of lungs Functions of mucociliary system Aerosol is the collection of particles/lipid droplets which are small enough to remain suspended in the air for a period of time. Aerosols suspended in air are inhaled Aerosols are classified as inhalable/PM 10 (10µ or less) and respirable/PM 2.5 (2.5µ or less) These inhaled particles are […]

Functions of lungs other then respiration Animals are exposed to pollutants like dusts, ammonia, pungent gases carbon monoxide, products of plant and animal origin, parasites, bacteria, viruses, spores, endotoxins, diesel fumes, ozonized oxides of nitrogen. During transport the animals and animals reared under intensive housing are exposed to stressor promoting agents like pneumonia/pleuritis. Non-infectious stress

Role of respiratory system in Acid–base balance Blood PCO2 can be varied extensively because the partial pressure of CO2 in alveoli determines the amount of CO2 dissolved in blood. The respiratory mechanism depends upon the sensitivity of respiratory control systems to change in blood PCO2 and pH. A small increase in PCO2 or decrease in pH stimulates pulmonary ventilation, so

Carbon dioxide equilibration curve and hypoxia CO2 equilibration curve The total quantity of CO2 combined with blood in all forms of transport of CO2 depends on PCO2, which can be expressed through the CO2 equilibration curve. The PCO2 ranges between 40mm. Hg in the atrial blood and 45mm. Hg in venous blood. At the capillary bed the concentration of

Carbon dioxide transport in respiration The CO2 produced during metabolism is a waste product and has been eliminated. The flow of CO2 is effected under a continuous pressure gradient. The transport of CO2 is effected in the following ways as physically dissolved CO2 and transport in chemical combination. 1. Physically dissolved CO2 Compared with O2, CO2 is 24 times

Transport of Oxygen in respiration Oxygen is transported in blood in two forms as physically dissolved O2 and O2 in combination with hemoglobin. 1. Physically dissolved O2 The O2 diffuses across the alveolar membrane and the lung capillary endothelium into the blood plasma where it is physically dissolved according to its solubility co-efficient and partial pressure. 0.003ml

Humoral Control of respiration Humoral control refers to those factors in the body fluids that influence ventilation like CO2, O2 and H+. The respiratory system functions to bring in O2 and eliminate CO2 from the body. This function is assisted by specialized receptors called chemoreceptors that monitor the levels of CO2, O2 and H+, and then send such information

Hering-breuer reflex The receptors for these reflexes are located in the lungs, particularly in the bronchi and bronchioles. The nerve impulses generated by these receptors are transmitted by fibers in the vagus nerves to the respiratory center. The effect of inflation-receptor stimulation is to inhibit further inspiration (stimulation of neurons in the dorsal respiratory group)

Neural Control of respiration Pulmonary ventilation is regulated closely to maintain the concentrations of H+, CO2, and O2 at relatively constant levels while meeting the needs of the body under varying conditions. If either the H+ or the CO2 concentration increases or if the O2 concentration decreases, their levels will be returned to normal by increasing ventilation. Conversely, if

Dead Space Ventilation The tidal volume is used to ventilate not only the alveoli, but also the airways leading to the alveoli. Because there is little or no diffusion of oxygen and carbon dioxide through the membranes of most of the airways, they com­pose part of dead space. The other part of dead space ventilation