Anatomy & Physiology 2 Canale Respiratory System: Exchange of Gases
Why is it so hard to hold your breath for Discuss! : ) a long time?
Every year carbon monoxide poisoning kills 500 people and sends another 40,000 to hospital emergency rooms. Why is carbon monoxide so deadly?
LOWER RESPIRATORY TRACT UPPER RESPIRATORY TRACT Human Respiratory System Nose Passageway for air Mouth Passageway for food and air Epiglottis Covers larynx during swallowing Pleural membranes Cover the lungs and line the chest cavity Nasal cavity Filters, warms, and moistens air Pharynx (Throat) Common passageway for air, food, and liquid Larynx (Voice box) Production of sound Trachea (Windpipe) Main airway Lung Organ of gas exchange Intercostal muscle Moves ribs during respiration Bronchi Branching airways Alveoli Air sacs for gas exchange Rib Right lung Left lung Diaphragm Skeletal muscle of respiration Figure 10.1
Respiration Processes Breathing (ventilation): moving air in and out of lungs External respiration: gas exchange between air and blood Internal respiration: gas exchange between blood and tissues Cellular respiration: oxygen use to produce ATP, carbon dioxide as waste inside the cell (mitochondria! ) Animation The Human Respiratory System
The Upper Respiratory Tract Sinuses Nasal cavity External nose Opening of the auditory tube Nostril Pharynx Tongue Epiglottis Glottis Larynx Trachea Esophagus Figure 10.2
Upper Respiratory Tract Functions 1. Passageway for respiration 2. Receptors for smell 3. Filters larger foreign material from incoming air 1. Moving cilia hair-like projections the mucus traps dust and foreign particles and cilia moves this to the back of nasal cavity where we cough it or swallow it. 4. Moistens and warms incoming air 5. Resonating chambers for voice
The Lower Respiratory Tract Larynx Trachea Right bronchus Clusters of alveoli Left bronchus Bronchioles Figure 10.3
Lower Respiratory Tract Functions 1. Larynx: maintains an open airway, routes food and air appropriately, assists in sound production 2. Trachea: transports air to and from lungs 3. Bronchi: branch into lungs 4. Lungs: transport air to alveoli for gas exchange
Gas Exchange Between the Blood and Alveoli Figure 10.8a (1 of 3)
Gas Exchange Between the Blood and Alveoli Exchange due to partial pressures /concentration gradients Figure 10.8a (2 of 3) and (3 of 3)
Breathing: Pressure Gradient Inspiration AND expiration: air in AND air out cycle 1. Relaxed state Diaphragm and intercostal muscles relaxed 2. Inspiration Diaphragm contracts, pulling muscle down; intercostal muscles contract, elevating chest wall and expanding volume of chest, lowering pressure in lungs, pulling in air 3. Expiration Muscles relax; diaphragm resumes dome shape; intercostal muscles allow chest to lower, resulting in increase of pressure in chest and expulsion of air
Respiratory Cycle Figure 10.9
Lung Volumes and Vital Capacity Tidal volume Volume of air inhaled and exhaled in a single breath Dead space volume Volume of air that remains in the airways and does not participate in gas exchange Vital capacity Maximal volume that can be exhaled after maximal inhalation
Lung Volumes and Vital Capacity Inspiratory reserve volume Volume of air that can be inhaled beyond the tidal volume Expiratory reserve volume Volume of air that can be forcibly exhaled beyond the tidal volume Residual volume Volume of air remaining in the lungs, even after a forceful maximal expiration Measured by spirometer
Measurement of Lung Capacity Figure 10.10a
Gas Exchange and Transport: A Passive Process Gases diffuse according to their partial pressures External respiration: gases exchanged between air and blood Internal respiration: gases exchanged with tissue fluids Oxygen transport: bound to hemoglobin in red blood cells or dissolved in blood plasma Carbon dioxide transport: dissolved in blood plasma, bound to hemoglobin, or in the form of plasma bicarbonate
How O 2 and CO 2 are Transported in Blood Figure 10.12 (1 of 2)
How O 2 and CO 2 are Transported in Blood Figure 10.12 (2 of 2)
Regulation of Breathing: Nervous System Involvement Respiratory center in the medulla oblongata Establishes basic breathing pattern Chemical receptors Monitor carbon dioxide, hydrogen ions, and oxygen levels Medulla Sensitive to hydrogen ions in cerebrospinal fluid resulting from carbon dioxide in blood
Regulation of Breathing Figure 10.13
Regulation of Breathing: Nervous System Involvement Carotid and aortic bodies Sensitive to carbon dioxide, ph, and oxygen levels Conscious control Resides in higher brain centers Ability to modify breath
Disorders of Respiratory System Reduced air flow 1. Asthma spasmodic contraction of bronchi 2. Emphysema - alveoli are permanently impaired 3. Bronchitis inflammation of the bronchi Infections 1. Pneumonia bacterial or viral infection inflamed lungs 2. Tuberculosis bacteria Mycobacterium tuberculosis 3. Botulism - Clostridium botulinum bacteria Disorders: 1. Lung cancer 2. Congestive heart failure 3. Cystic fibrosis
True or false? Production of mucus is not a normal part of the respiratory system. True False
True or false? The pulmonary artery carries blood that is low in oxygen. True False
Doctors measure lung function by having a person inhale and then exhale forcibly into a device called a spirometer. What does a spirometer measure? A. The volume of air that a person can breathe in and out in a single breath B. How quickly air can be moved in and out of the lungs C. How much muscle the lungs have D. Both A and B
The chemicals in tobacco smoke. A. increase mucus production B. destroy cilia C. cause mucus pooling, leading to infections D. All the above
Gas exchange in the respiratory system occurs in the. A. trachea B. bronchiole tree C. alveoli D. pleural cavity
When you take a deep breath then hold it, you are using your. A. tidal volume B. inspiratory reserve volume C. expiratory reserve volume D. vital capacity
Most of the carbon dioxide carried in the blood is in the form of. A. oxyhemoglobin B. dissolved carbon dioxide C. carbonic acid D. bicarbonate
The principle chemical monitored in the respiratory system is. A. oxygen B. carbon dioxide C. carbonic acid D. oxyhemoglobin