Histology of trachea

Histology Study Guide Respiratory Tract These notes are an ancillary resource, NOT a substitute for scheduled resource sessions or for textbooks.If you use this on-line study aid, please refer to your • • • • • • • • • • Respiratory region • • • • RESPIRATORY IMAGE INDEX SAQ Self Assessment Questions Preparation Before studying the histology of any particular system or organ, one should appreciate the basic concepts and tools of histology, as presented in the Introduction to Histology at this website. In particular, one should be familiar with the Overview of Respiratory Tract Histology The lung is one of several organs that packs a large epithelial surface area into a compact volume. The basic organizational pattern is that of a • Both in large glands and in the respiratory system, a system of conducting passageways form a branching "tree," with functional units at the end of each twig. • In the respiratory system, the tree's "trunk" is the • In the The pleural cavity is lined by mesothelium. This includes both the outer surface of lung and the adjacent inner surface of the chest wall. ( Note that "outer surface" in the above paragraph refers to the surface that a surgeon encounters upon opening the ribcage, while "inner surface" refers to the gas-exchange membranes "inside" the lung. These "inner" surfaces actually face inspired air, and are therefore more properly the "outer" surfaces of alveolar epithelium. The conducting passageways of the respiratory system (nasal ca...

• Know the basic components of the conducting and respiratory portions of the system and describe distinctive structural features of each component related to particular functions in respiration. • Know the types of cells present in the respiratory epithelium and their functions in respiration. • Be able to identify the trachea, bronchi, terminal bronchioles, respiratory bronchioles, alveolar ducts and alveoli of the respiratory tract on the basis of: • epithelial cell types present, and • relative amounts of glands, cartilage, smooth muscles and connective tissue fibers present in the wall of the tubes. • Be able to name the cellular and structural elements that form the blood-air barrier. • Know the vascular supply of lungs and be able to identify the pulmonary artery, pulmonary vein, and the bronchial artery on the basis of location, structure, and tissues supplied. For descriptive purposes the respiratory system is divided into (a) conducting and (b) respiratory portions. The conducting part consists of passageways which carry air to the respiratory portion. The respiratory portion begins at the level where alveoli first appear in the final branches of the bronchioles. Respiration (gaseous exchange between blood and air) occurs across the walls of the alveoli. The conducting portion includes parts which are outside the lung or extrapulmonary (nasal cavities, nasal pharynx, larynx, trachea and primary bronchi), and those which are inside the lung or intrapulmonary (rest...

• Be able to describe the layers in the wall of the digestive tract (mucosa, submucosa, muscularis (propria), and adventitia/serosa), and explain how they differ in the pharynx, esophagus, and stomach. • Know the histological differences in the pharynx and the upper, middle and lower portions of the esophagus. • Be able to recognize gastric glands, identify their constituent cells, and know their secretory products. • Be able to differentiate gastric glands, cardiac glands, and pyloric glands. The wall of the gastrointestinal tube consists of 4 major layers (W pgs 263-266): the mucosa, the submucosa, the muscularis (also called muscularis propria or muscularis externa) and the serosa (if covered by peritoneum) or adventitia (if retroperitoneal). The mucosa, in turn, consists of an epithelium, a supporting lamina propria of loose connective tissue and a thin, usually double, layer of smooth muscle, themuscularis mucosae. The four major layers will be examined in each region of the digestive system. The mucosa differs considerably from region to region, reflecting changing functional activity. Be sure to identify these differences. The other layers in the wall change rather little, although there are subtle differences also in these layers that can also help you identify particular regions of the GI tract. To help you keep track of changes in the various layers, you can fill in this spreadsheet as you work through today's and next week's labs. Slide 152 40x (H&E) Slide 152 t...

Basic Tissue Types Histology is the study of tissues. All of the various tissues of the human body can be categorized into four basic tissue types (see four basic tissue types can greatly simplify your understanding of the cellular composition of the many organ systems. • OVERVIEW ( • • Descriptions of the four basic tissues • • • • • • • • Useful terms: • • See AnatomyLove for a less-formal, more chatty presentation of the four basic tissue types (and more). Overview of the Four Basic Tissue Types epi, on + thelium, surface). Epithelial tissue consists of cells attached to one another to form an uninterrupted layer of cells that separates the underlying tissues from the outside world. The body's epithelium not only covers the body's obvious surfaces (such as the epidermis of the skin and the linings of respiratory, urinary, and digestive tracts) but also extends into all of the complex invaginations which form lungs, kidneys, sweat glands, digestive glands, liver, etc. Epithelial tissue provides the essential functions of protection, containment, absorption, and secretion. It keeps bad stuff out, keeps bodily fluids in, and moves materials in and out. Embryonically, most epithelial tissues are derived either from ectoderm (e.g., epidermis) or endoderm (e.g., epithelium of trachea and lung). [ Muscle Tissue is specialized for gross movement by means of cellular contraction. Embryonically, muscle derives from mesoderm or mesenchyme. [ A note on pathology nomenclature: The n...

Eukaryotic cell Histology is the science of the microscopic structure of Key facts about histology Histology Microanatomy or microscopic anatomy, The study of cells and tissues, from their intracellular components to their organization into organs and Cell structure Cellular membrane, cytoplasm, organelles, nucleus Tissues A unity of cells with a similar structure that as a whole express a definite and unique function. Epithelial, connective, muscle, nervous Organs A unity of tissues with a more complex set of functions, defined by the combination of structure and function of the comprising tissues Systems of organs A group of organs united by similar functions. Cardiovascular, nervous, integumentary, musculoskeletal, respiratory, digestive, excretory, endocrine, lymphatic, reproductive Histology techniques Tissue preparation, tissue staining, microscopy, hybridisation + Show all Cells and tissues A nucleus and cytoplasm. The cytoplasm contains specialized subunits called Thoroughly learn the parts of a cell using our The DNA is condensed and coiled up into chromosomes. All cells are enveloped by a semipermeable two-layered membrane, which serves as a dynamic medium for the cell’s interaction with the external environment. Kind of like border police, it controls everything that comes in or out of the cell. Cells are categorized into various types, all of which perform different functions. These include epithelial cells, Cells and tissues Explore study unit Epithelial ti...