Respiratory System ppt 1-10

Movement of air in and out of the respiratory system

Internal respiration

internal respiration

use of oxygen by cells to generate ATP

• Air is moved thru without gas exchange
• =anatomical dead space
• From nasal passage to the terminal bronchioles

• Upper respiratory system
• =filters, warms and humidifies incoming air

alveoli(pulmonary)

-when alveoli are damaged and can not exchange gases

=physiological dead space

• Provide the major source of resistance to air flow in the respiratory system
• Brochiolar constriction -
• caused by parasympatheic stimulation
• --> Acetylcholine, or immune cells
• --> Histamine

• Sympathetic stimulation
• -->Norepinephrine, or adrenal medulla stimulation
• -->E + NE release (neurohormones)

• =region of gas exchange
• -(150million/lung) each is surrounded by capillaries

-gas diffusion occurs across single layer of alveolar epithelial cells

-fused basement membrane of alveoli + capillary, single layer of endothelial cells

• produce surfactant
• -reduced surface tension of alveolar fluid
• -keep alveoli expanded and prevent collapse

phagocytize particles that reach the alveoli (PM<2.5 Microns)

• Serous membrane made by two layers separated by pleural fluid
• -parietal pleura
• -visceral pleura

covers inner surface of thoracic wall

covers the outer surface of the lung

• pressure on the fluid between the two layers of pleura
• -plays a role in expansion and compression of the alveolar walls, air pressure in the lungs and air movement in and out of lungs

• Goblet cells in the epithelium
• Mucous glands in the lamina propria produce sticky mucous
• -increased by exposure to contaminants in air

• Cilia in the nasal cavity sweep the mucous down to the pharynx; Cillia in URT sweep mucous up to the pharynx
• =muco-ciliary escalator

• -atmospheric pressure (760 mm Hg) > alveolar pressure (759mmHg aka -1mm Hg)
• -(-1 mm Hg is adequate for quiet breathing, deep rapid inhalation requires: -20 to -30 mm Hg difference)

alveolar pressure > atmospheric pressure

• requires inspiratory skeletal muscle contration.
• increases the size of the thoracic cavity --> decreased alveolar pressure