Human Respiratory System

Human Respiratory System - 1 The Human Respiratory System...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1 The Human Respiratory System NPB 101L I ntro The respiratory system exchanges gas between the environment and the body. o There are two primary processes: internal respiration the utilization and production of gas in the mitochondria and external respiration gas exchange across respiratory epithelia in the lungs o While this system has many functions, including vocalization, regulation of temperature and regulation of pH, this lab focuses on pulmonary ventilation - the movement of air into and out of the lungs (i.e. breathing) The Lungs Located in the thorax, which is the compartment found between the neck and the abdomen o The thorax is completely separated from the abdomen by the diaphragm. o The walls of the thorax are formed by the spinal cord, ribs, sternum, and intercostal muscles A pleural sac surrounds each lung. This sac has two layers separated by a fluid-filled cavity. This intrapleural fluid lubricates the pleural surfaces so they can slide over one another during breathing The Airways When you breath in, air passes through either your nose or mouth and enters the pharynx o The pharynx divides into two tubes, the esophagus and larynx. Air enters the larynx, which then opens into a long tube known as the trachea. The nose, mouth, pharynx, and larynx comprise the upper airways. The trachea branches into two bronchi, one of which enters each lung. 2 o Within the lung, there are over 20 generations of branching, each resulting in shorter, narrower, and increasing numbers of tubes Branches are as follows: Bronchi bronchioles terminal bronchioles respiratory bronchioles alveolar ducts alveolar sacs The conducting zone contains no alveoli so there is no gas exchange within these airways The respiratory zone is the region where gas exchange occurs with the blood Major site of gas exchange is at the alveoli The pulmonary blood vessels also undergo numerous branching o The smallest vessels branch into networks of capillaries that surround the alveoli Lung Volumes Tidal volume (TV) is the volume of air inspired and expired with a normal breath o I t is approximately equal to 500 ml The additional volume of air that can be taken into the lungs following tidal inspiration is known as inspiratory reserve volume (IRV). ~ 3000 ml 3 Expiratory reserve volume (ERV) is the additional amount of air that can be expelled from the lungs after a passive expiration. ~ 1000 ml Residual volume (RV) is the volume of air remaining in the lungs after a maximal, forced expiration. ~ 1200 ml Total Lung Capacity (TLC) = TV + RV + ERV + IRV Functional Lung Capacity (FRC) = RV + ERV o This capacity is functional because it provides a reservoir for oxygen during expiration when oxygen rich air is not being delivered to the lungs o I t is also acts as a buffer to minimize inspiratory and expiratory swings in alveolar and blood CO2....
View Full Document

This note was uploaded on 03/15/2010 for the course NPB101L 83009 taught by Professor Liets during the Winter '09 term at UC Davis.

Page1 / 11

Human Respiratory System - 1 The Human Respiratory System...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online