Boyle's Law and The Respiratory System: Boyle's law describes the relationship between the pressure and volume of a gas; dictates the mechanics of respiration. • Boyle's Law Equation: (P1)(V1) = (P2)(V2) - Pressure and volume of a gas are inversely related (assume temperature is constant).Key anatomical/mechanical structures - Pair of lungs connected by a trachea - Lungs sit within a double-walled pleural sac, which separates lungs from thoracic wall. - Pleural space, which is the potential space within sac. - Sternum and ribs around pleural sac - The internal and external intercostal muscles lie between the ribs - Diaphragm comprises a sheet of skeletal muscle and forms bottom border of thoracic cavity. – Contraction/relaxation changes the volume of the thoracic cavity, which alters the intrapulmonary and intrapleural pressures in accordance with Boyle's law. Air pressures Dictate movement of air during inspiration and expiration - Atmospheric pressure = 760 mm Hg, external to the thoracic cavity. - Intrapulmonary pressure (intra-alveolar pressure) = atmospheric pressure at rest, refers to the pressure within the lungs - Intrapleural pressure = 756 mmHg, pressure in the pleural space.Inspiration: actively increases thoracic volume. Movements during Inspiration: • Diaphragmatic Contraction: - Diaphragm flattens and moves inferiorly as it contracts. • External Intercostal Muscle Contraction: - External intercostal muscles contract - Forces sternum to move in an anterior and superior directionEffects: • As thoracic volume increase: – Intrapulmonary pressure decreases to below atmospheric pressure; creates pressure gradient that facilitates inhalation. – Air moves down this pressure gradient: Moves from atmosphere (high P) through trachea into lungs (low P) • Gas exchange occurs in lungs ? need to exhale carbon dioxide Expiration passively decreases thoracic volume. Movements during Expiration: – Diaphragm relaxes – Ribs back to resting position (move medially) – External intercostal muscles relax – Sternum back to resting position (moves inferiorly)Effects: • As thoracic muscles relax: – Lungs elastically recoil to their pre-inspiratory volume; Lung volume decreases. – Intrapulmonary pressure increases above atmospheric pressure; creates pressure gradient that facilitates expiration. – Air moves down pressure gradient: Moves from lungs ? out trachea ? into atmosphere, CO2 exhaled.Compliance Flow Rate
Diffusion is the physical process of the natural movement of ions or molecules. It occurs in both liquids and gasses and is important to all ...
MITOCONDRIAS Y CLOROPLASTOS (Biologia Celular CBC)
Farmacología antibióticos cuadro conceptual.
Molares y Premolares
Músculo Temporal
A más de 8.600 kilómetros de casa, Carles Vilariño-Güell no imaginaba que entre aquellas trece mil muestras de ADN se encontraba el Santo Grial de la esclerosis múltiple. Cuando comenzó a trabajar con Dessa Sadovnick, la tarea titánica que ambos abordaron parecía imposible: encontrar la causa genética de una enfermedad autoinmune que afecta a más de 2,5 millones de personas en el mundo. Como si de dos Quijotes se tratara, Vilariño-Güell y Sadovnick comenzaron su particular lucha de gigantes. ¿El objetivo? Encontrar el primer gen que produjera esclerosis múltiple, algo calificado por la ciencia como imposible durante más de cuarenta años.
Articulación Temporomandibular
