Respiration

The Bronchi
• The bronchial tree terminates in the alveoli, which are the tiny air sacs supporting a network of capillaries from pulmonary blood vessels. • The function of the bronchi is to provide a passageway for air to and from the lungs.
Chapter 6
Respiratory System
Anatomy and Physiology Overview
• The respiratory system consists of the nose, pharynx, larynx, trachea, bronchi, and lungs. • Its primary function is to furnish O2 for use by individual tissue cells and to take away CO2. • This process is accomplished by the act of respiration.
The Lungs
• Pleura – A serous membrane composed of six layers that enclose the lungs. • Pleural Cavity – A space between parietal and visceral pleura and contains serous fluid that lubricates and prevents friction.
• Upper Respiratory Passageways • Lower Respiratory Passageways and lungs
The Nose
• The nose has five functions: – Serves as an air passageway. – Warms and moistens inhaled air. – Its cilia and mucous membrane trap dust, pollen, bacteria, and other foreign matter. – Contains olfactory receptors, which sort out odors. – Aids in phonation and the quality of voice.
The Bronchi
• Are the two main branches of the trachea. • The trachea divides into the right bronchus and the left bronchus. • Each bronchus enters the lung at a depression, the hilum. They then subdivide into the bronchial tree composed of smaller bronchi, bronchioles, and alveolar ducts.
The respiratory system: nasal cavity, pharynx, larynx, trachea, bronchi, and lungs with expanded views of the trachea and alveolar structure.
The respiratory system
Respiration
• The Vital Function of Respiration • Respiratory Rates
Vital Function
• The process of respiration is interrelated with other systems of the body. • The medulla oblongata and the pons of the CNS regulate and control respiration. • Respiration, along with temperature, pulse, and blood pressure, is a vital sign that aids in determining an individual’s state of health.
Larynx, trachea, bronchi, and lungs with an expanded view showing the structures of an alveolus and the pulmonary blood vessels.
The Lungs
• Cone-shaped, spongy organs of respiration lying on either side of the heart within the pleural cavity of the thorax. • They consist of elastic tissue filled with interlacing networks of tubes and sacs that carry air and blood vessels carrying blood. • The main function of the lungs is to bring air into intimate contact with blood so that O2 and CO2 can be exchanged in the alveoli.
Gas Transport
• O2 is carried in the blood bound to hemoglobin in RBC. • CO2 is mostly converted to an acid called carbonic acid. • Hyperventilation vs. Hypoventilation Alkalosis vs. Acidosis
The Pharynx
• known as the throat, it is a musculomembranous tube that extends from the base of the skull, anterior to the cervical vertebrae, and becomes continuous with the esophagus. • The functions of the pharynx are: – Passageway for air. – Passageway for food. – Aids in phonation by changing shape.
The Trachea
• The trachea is composed of: – Smooth muscle – Is reinforced at the front and side by C-shaped rings of cartilage. – Mucous membrane – Lining that contains cilia, which sweep foreign matter out of the passageway.
The Pharynx
• It is divided into three portions – Nasopharynx • Located behind the nose. – Oropharynx • Located behind the mouth. – Laryngopharynx • Located behind the larynx.
Nose, nasal cavity, and pharynx: nasal cartilages and external structure
Nose, nasal cavity, and pharynx: sagittal section of the nasal cavity and pharynx.
The Lungs
• The Diaphragm – The musculomembranous wall that separates the thoracic cavity from the abdominal cavity.
• Mediastinum – The central portion of the thoracic cavity, between the lungs, which contains the heart and other structures.
The Trachea
• Also known as the windpipe; a cartilaginous tube that is the air passageway extending from the pharynx and larynx to the main bronchi. • Its function is to provide an open passageway for air to the lungs.
The Larynx
• Also called the voicebox; a muscular, cartilaginous structure lined with mucous membrane. • It is the enlarged upper end of the trachea below the root of the tongue and hyoid bone.
Cleaning System
• Cells lining in the trachea and bronchial can secrete mucus, which traps foreign matters. • Cells in the bronchi containing cilia, which push the mucus up out of the airways by constant wavelike motions. • Foreign matters are ejected as sputum from the bronchi by a cough. • Macrophages can swallow up foreign particles or destroy them with enzymes.