Portage Learning A&P 1 - Module 2

Portage Learning A&P 1 - Module 2 Gross Anatomy - Study of structures that can be seen with the naked eye Gross Anatomy of the Lungs - The right lung has three lobes while the left lung has two lobes. The both lungs have oblique fissures. The right lung also has a horizontal fissure separating the superior and middle lobes hilum - the root where the pulmonary blood vessels and veins enter the lung. This is also where the trachea turns into the bronchi. pleura - membranes that cover the surface of the lung and the cavity surrounding the lungs parietal pleura - covers the surfaces surrounding the lungs: the rib cage, diaphragm, and mediastinum. visceral pleura - directly covers the lungs pleural space/cavity - The space that is formed between the pleurae. Normally, this space is empty except for a scant amount of fluid. However, in the diseased state, this cavity can fill with air or fluids. anatomical organization of the respiratory system - allows the respiratory system to perform three main functions: 1) air conduction, 2) air filtration, and 3) exchange of gases - aka respiration Conducting portion of respiratory system - responsible for moving air in and out of lungs. air is filtered so that it is free of debris, warmed, and humidified. By the time the air reaches the lungs, it is at body temperature and saturated with water. nostril - have hair and cilia that filter the air , have goblet cells that trap nasal cavities - aka fossae, composed of bone and cartilage, are made up of several parts. The left and right fossae are separated by the nasal septum. vestibule - is the most external portion of the nasal cavity just inside the nostrils.It is covered with stratified squamous epithelium. Inside are short thick hairs to catch debris. Down the middle is a nasal septum. nasal conchae - found in nasal cavity. responsible for warming air as it moves past. Important so the body can do less work during respiration. We want air to be warm and moist before it enters the lungs Pharynx - Throat; the membrane-lined cavity behind the nose and mouth, connecting them to the esophagus. Has 3 parts: nasopharynx, oropharynx, laryngopharynx nasopharynx - connection area between the nasal cavity and pharynx, generally above the soft palatehas this name bc connects to nasal cavity oropharynx - caudal to the mouth and anterior to the epiglottis. Has this name bc located behind oral cavity. laryngopharynx - area where the pharynx, larynx and esophagus meet. Stratified squamous epithelium protects these tissues from frictional damage. Esophagus - lies posterior to the larynx and trachea. It is a muscular tube connecting the pharynx with the stomach. It is lined with mucosa. It is the tube that is used for food and nutrients. Trachea (windpipe) - passageway for air from larynx to the bronchi. It is composed of about 20 Cshaped, cartilaginous rings that do not completely meet on the posterior side of this tube- they help hold open airway. hard palate and soft palate - separate oral cavity from nasal cavity hard palate - roof of the mouth soft palate - closes nasal cavity when we are eating to make sure food and liquid do not enter the nasal cavity. aspiration - when food or liquid accidentally enters the trachea. This may happen because bothfood and air cross in this region. Larynx - Attached to the trachea. Can physically feel going up and down when you swallow. This tube is permanently held open to receive air. It is made up of single cartilages and paired cartilages. It is the area that includes the Thyroid, Epiglottis, glottis, cricoid cartilage and vocal cords. single cartilages - thyroid cartilage, cricoid cartilage, epiglottis paired cartilages - arytenoids, corniculates, cuneiforms- are smaller in size to the single cartilages Epiglottis - located in the oropharynx behind the oral cavity- this flap directs food and fluid away from the trachea and into the esophagus. It is a cartilage flap that moves like a trap door. glottis - an opening into the larynx, or voice box. The vocal cordsor folds are also located in the larynx. vocal folds (true vocal cords) - located at the edge of the glottis, embedded in mucous membranes. Flexible and pliable bands of connective tissue vibrate and produce sound when air is expelled past them through the glottis from the larynx. pneumonia - Bacterial infection of the lungs Bronchi - two short branches located at the lower end of the trachea that carry air into the lungs. The bronchi resemble the trachea in structure, but as the tubes divide and subdivide, their walls become thinner, and rings of cartilage are no longer present. Bronchioles - progressively smaller tubular branches of the airways respiratory epithelium - lines the entire bronchial tree. This is primarily made of ciliated, pseudostratified, columnar cells. bronchial tree - branched airways that lead from the trachea to the microscopic air sacs called alveoli primary bronchi - the two passageways that branch off the trachea and lead to the right and left lungs secondary bronchi - branches of the primary bronchi that lead to each lobe of the lung; also called lobar bronchi tertiary bronchi - branches of the secondary bronchi that divide into bronchioles; also called segmental bronchi terminal bronchioles - the smallest air conducting bronchioles. respiratory bronchioles - the transitional zone between conduction and respiratory. in the respiratory system concerned with both air conduction and gas exchange. Alveolar ducts, alveolar sacs, and single alveoli extend from the ends of the respiratory bronchioles. Alveoli - are primary way that gasses are exchanged. They are wedged between capillaries. Heavily vascularized area bc must have a lot of blood flow to be able to exchange all the gasses we need for our body. The primary function of the cells within the alveoli is to allow efficient exchange of gases between the air and blood. Histology - the study of the cellular anatomy of a tissue or organ that can be viewed through a microscope.A cellular view Cilia - small hair like projections at the apex or the top of the cells (apical side). These hairs move or "beat" in an upward sweeping motion. Their action helps to keep the respiratory tract free of debris. basement membrane - "floor" of the epithelial tissue. Pseutostratified Columnar - cells that appear to be in layers. (typical respiratory epithelium) stratified squamous epithelium - can be found at the entrance of the respiratory system. Stratified means layered and squamous means flattened. This means that stratified squamous epithelium is found in multiple flattened layers. One example of this type of epithelium in the respiratory tract is found just inside the nostril (vestibule) of the nose simple squamous epithelium - In the smaller bronchioles, the epithelium transitions into simple squamous epithelium. Simple refers to the presence of only one layer of cells. Simple squamous refers to a single layer of flattened cells. This is important for gas exchange- co2 leaves, o2 enters, the barrier must be thin, thus simple= one layer goblet cells - these cells produce mucus, catch debris and move it out. are also present within the epithelium of the respiratory tract. Named for their wineglass (or goblet) like appearance. are found in the nostrils, Trachea and bronchi columnar cells - attach to basement membrane, called columnar because they are taller than they are wide Type I alveolar cells - make up 95% of alveolar epithelium. They form the very thin, simple squamous epithelium of the alveoli in junctionwith capillaries. type 2 alveolar cells - make up 5% of alveolar epithelium and are dispersed throughout the Type I cells. Type II cells have a variety of functions. One function is to produce and secrete pulmonary surfactant, which is needed throughout the alveolar surface tokeep the alveoli open. In addition, Type II cells can divide to replace damaged Type I cells.Type 2 also produces surfactant Surfactant - A lipoprotein that covers the luminal surface and keeps the alveoli from sticking together during exhalation. Helps break up water to keep all the alveoli open alveolar macrophages - they are the most abundant cell within the alveoli.They are the primary immune defense system of the alveoli. Once a macrophage has phagocytized a particle or pathogen, it migrates toward the ciliary surface of the bronchiolar system. Once on the surface, the cilia carry the macrophage and particles to the mouth to be expectorated or swallowed.