Anatomy Exam 2 Study Sheet Pt. 2 PDF

Anatomy Exam 2 - - - - - Ch. 22A The respiratory system supplies the body with oxygen and disposes of carbon dioxide through the processes of pulmonary ventilation (moving air in and out), gas exchange (exchange of oxygen and carbon dioxide: internal (in tissues) and external (in lungs) respiration,...

Anatomy Exam 2 - - - - - Ch. 22A The respiratory system supplies the body with oxygen and disposes of carbon dioxide through the processes of pulmonary ventilation (moving air in and out), gas exchange (exchange of oxygen and carbon dioxide: internal (in tissues) and external (in lungs) respiration, and cellular respiration (cells use oxygen to make ATP). The respiratory system consists of two zones, conducting and respiratory, for moving air and facilitating gas exchange in the lungs and tissues. The principal organs of the respiratory system include the nose, paranasal sinuses, pharynx, larynx, trachea, bronchi, and lungs (alveoli) in the conducting and respiratory zones. The nose and nasal cavity function to warm, cleanse, and humidify inhaled air, amplify the voice, and aid in the sense of smell. The pharynx, or throat, is a muscular funnel extending from the nasal cavity to the larynx, consisting of the nasopharynx (lined with respiratory epithelium), oropharynx (stratified squamous epithelium), and laryngopharynx (lined with stratified squamous epithelium) regions. The larynx, or voice box, is a cartilaginous chamber with the primary function of keeping the airway open and guarding the superior opening of the larynx with the epiglottis. It has evolved to also facilitate phonation and sound production. - Epiglottis: flap of tissue that guards the superior opening of the larynx The larynx contains vocal ligaments and is covered with stratified squamous epithelium The glottis refers to the vocal cords and the opening between them, which includes the vestibular fold and vocal fold Intrinsic muscles control the vocal cords, producing different pitches and controlling loudness The trachea is a rigid tube about 10-12cm long and 2cm in diameter, reinforced by 16 to 20 C-shaped rings of hyaline cartilage - The trachea is lined with ciliated pseudostratified columnar epithelium and contains lymphatic nodules, mucous and serous glands, and the adventitia, which contains the cartilage rings and the carina - The bronchial tree is a branching system of air tubes in each lung, consisting of main (primary) bronchi, lobar (secondary) bronchi, and segmental (tertiary) bronchi - All bronchi are lined with respiratory epithelium, with cells growing shorter and the epithelium thinning distally, and a well-developed layer of smooth muscle in the mucosa - The bronchial tree relaxes to constrict or dilate the airway, regulating airflow - All divisions of the bronchial tree contain a large amount of elastic connective tissue, contributing to the recoil that expels air from the lungs - Cartilage becomes irregular and disappears entirely by the time the bronchioles are reached - The bronchioles lack cartilage, are 1mm or less in diameter, and have a well-developed layer of smooth muscle - The terminal bronchioles have no mucous glands or goblet cells and have cilia that move mucus draining into them back by the mucociliary escalator - Respiratory bronchioles have alveoli budding from their walls, divide into alveolar ducts, and end in alveolar sacs - There are 150 million alveoli in each lung, providing about 70m2 of surface for gas exchange - Alveoli contain squamous (type I) alveolar cells, great (type II) alveolar cells, and alveolar macrophages - Each alveolus is surrounded by a mesh of capillaries supplied by the pulmonary artery and contains a respiratory membrane, which is the barrier between the alveolar air and blood - Lungs are cone-shaped organs with a broad concave base resting on the diaphragm and a costal surface pressed against the ribcage - The lungs consist of the right and left lungs, each with different features and lobes. - The right lung is shorter due to the higher position of the liver and has three lobes separated by fissures. - The left lung is taller and narrower due to the position of the heart, with two lobes separated by a single oblique fissure. - The pleurae consist of the visceral pleura that covers the lungs, and the parietal pleura that adheres to the mediastinum, rib cage, and diaphragm. - The pleural cavity is a potential space between the pleurae containing pleural fluid, which reduces friction and creates a pressure gradient to assist lung inflation. - - Ch. 22B Atmospheric pressure (AP) is 760 mm Hg (1 atm) Intrapulmonary pressure (IP) is the pressure within the alveoli Intrapulmonary pressure can be above or below atmospheric pressure Lung collapsing forces include elastic recoil of the tissue and surface tension of the alveolar fluid, opposed by the elasticity of the chest wall Pneumothorax can cause the visceral pleura to detach from the chest wall, affecting lung forces Ventilation involves volume changes leading to pressure changes, which equalize gas pressures Inspiration involves increasing the volume of the thoracic cavity and the diaphragm and external intercostals muscles Expiration is a passive process depending on lung tissue elasticity Forced ventilations involve specific muscles for deep or forced inspiration and expiration Physical factors that influence ventilation include airway resistance, alveolar surface tension, and lung compliance Respiratory volumes include total lung capacity, tidal volume, inspiratory and expiratory reserve volume, and residual volume Dead space includes anatomical and alveolar types, affecting gas exchange and total ventilation. Minute ventilation is the total amount of gas that flows in or out of the respiratory tract in one minute, and can reach up to 6L/min at rest and up to 200L/min during vigorous exercise. Alveolar ventilation rate is a better measure of gas exchange, calculated by multiplying breaths per minute by the difference between tidal volume and dead space volume. - Medullary control centers, including the ventral respiratory group and dorsal respiratory group, play a key role in generating respiratory rhythm and integrating input from stretch and chemoreceptors. - The pontine respiratory center modifies inspiratory neurons and is involved in activities such as speech, sleep, exercise, and singing. - Control of respiration is also affected by pH levels in the body. Ch. 22C - Properties of gases - Boyle’s law - Dalton’s law of partial pressure - Individual gases in a mixture each exert their own - Henry’s law - When gas is in contact with a liquid, the gas will dissolve in the liquid in proportion to its partial pressure - Gas dissolution in a liquid is proportional to its partial pressure - Molecules move between phases to reach equilibrium - Solubility determines the amount of gas that dissolves - Temperature affects solubility - Composition of Air - Alveolar air is different due to gas exchange and humidification - Consists of a mixture of old and new air - External & Internal Respiration - Pulmonary gas exchange - Oxygen moves into the blood and CO2 moves into the alveoli - Thickness and surface area of respiratory membrane are crucial - Partial pressure gradients and gas solubilities influence gas exchange - Ventilation-perfusion coupling is necessary for efficient gas exchange - Tissue gas exchange - Oxygen moves into the tissues and CO2 moves into the blood - Oxygen Transport - Ways oxygen is transported in the body - Dissolved in the plasma (1.5%) - Bound to hemoglobin (98.5%) - Oxyhemoglobin - Reversible binding regulated by several factors - Hypoxia - Inadequate oxygen delivery to tissues - Anemic: decreased RBCs, abnormal Hb - Ischemic: blocked circulation - Histotoxic: normal delivery but cells can properly use it - Hypoxemic: reduced arterial O2 - Carbon monoxide poisoning - Carbon Dioxide Transport - Ways carbon dioxide is transported in the body - Dissolved in the plasma (7-10%) - Bound to hemoglobin (~20%) - Carbaminohemoglobin - Bicarbonate ion (~70%) - Formation and regulation - Role in the carbonic acid-bicarbonate buffer system - - - Ch. 22D Chronic obstructive pulmonary disease (COPD) includes emphysema and chronic bronchitis. Emphysema involves enlarged alveoli, loss of elasticity, and damage to pulmonary capillaries. Chronic bronchitis results from inhaled irritants causing excess mucus, inflammation, and fibrosis, leading to increased infections. Smoking is a major risk factor for COPD, with different presentations known as "pink puffers" and "blue bloaters" based on symptoms and physical appearance. Asthma is characterized by episodes of coughing, dyspnea, wheezing, and chest tightness, often due to bronchospasms and allergic reactions. Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis, affecting one-third of the world's population and often contained in tubercles, with drug-resistant strains and lengthy therapy requirements. Lung cancer is a leading cause of cancer death, often related to smoking and characterized by low survival rates and types such as adenocarcinoma (peripheral lung nodules), squamous cell carcinoma (epithelium of the bronchi, causes bleeding), and small cell carcinoma (clusters of cells that grow into the mediastinum)