Respiratory System Chapter 14

Introduction https://www.youtube.com/watch?v=bHZsvBdUC2I https://www.youtube.com/watch?v=Cqt4LjHnMEA

Functions of the Respiratory System Inspiration – inhaling or breathing in Expiration – exhaling, or breathing out There are 4 respiratory jobs: Breathing: entrance and exit of air into and out of the lungs External respiration: the exchange of gases between air and blood Internal respiration: the exchange of gases between blood and tissue fluid Transport of gases to and from the lungs and the tissues These jobs are required for cellular respiration to continue

Respiratory Tract The path of air from the nose to the lungs The airway cleanses, warms, and moistens the air before it gets to the lungs

Upper Respiratory Tract Respiratory Tract – pg 277 Upper Respiratory Tract Nasal cavities Pharynx Glottis Larynx Lower Respiratory Tract Trachea Bronchi Bronchioles Lungs

The Nose Nasal conchae- warm and moisten air that is breathed in Cilia on the cells that line the nasal cavity have odor sensors The lacrimal glands drain into the nasal cavity This is why your nose gets runny when you cry!

The pharynx Connects the nasal and oral cavities Contains the tonsils which are lymphatic tissue that contain antigens which help fight off pathogens that may enter. Air passageway and food passageway cross paths

The larynx Triangular cartilaginous box Passageway into the larynx is called the glottis The glottis is surrounded by the vocal chords During puberty the growth of the larynx explains the males crackling voice and larger adam’s apple When you swallow the larynx moves upward to close the glottis The epiglottis, which is a flap above the larynx also comes down to close the passageway

Trachea (the “windpipe”) Surrounded by cartilage “C” shaped rings so that it doesn’t collapse Mucous and cilia keep this airway clean of debris Mucous is secreted by goblet cells.

Trachea (the “windpipe”) Tracheostomy – is an operation to put in an artificial breathing tube Smoking is known to destroy the cilia and this is why soot builds up in smoker’s lungs.

Bronchial Tree Trachea divides into the right and left bronchi Those primary bronchi branch off into smaller bronchioles During an asthma attack the bronchioles contract causing the characteristic wheezing Bronchitis is inflammation of the bronchi

Lungs Right lung has three lobes and the left has two lobes Each lung is enclosed in a double membrane called the pleura Between the membranes is a fluid that prevents friction The lungs are composed of alveoli – small air sacs The alveoli walls are thin and covered with capillaries Oxygen and carbon dioxide diffuse across the alveoli and capillary boundaries

Isssues with Breathing Emphysema is a degenerative disease that breaks down the walls of alveoli reducing the amount of surface area for gas exchange Often caused by smoking Makes it difficult to breathe Pneumonia is a viral or bacterial infection in which the bronchi and alveoli fill with thick fluid

Homeostasis How does the respiratory system have to work with other systems of the body? Circulatory, nervous, skeletal, muscular, digestive, etc…