Cells lining respiratory tract histology hand drawn
Answers
Explanation:
RESPIRATORY SYSTEM
The complex of organs and tissue which are necessary to exchange blood carbon dioxide (CO2) with air oxygen (O2) is called the respiratory system. It consists of
structures, which function as ducts, and which together are called the conductive portion of the respiratory system
structures which form the respiratory portion of the respiratory system, in which the exchange of CO2 and O2 is occurring and
the parts of the thoracic musculo-skeletal apparatus and specialisations of the lung which allow the movement of air through the respiratory system - the ventilating mechanism.
Nasal Cavity
The Nasal cavity is divided into three structurally and functionally different parts.
The vestibules (the first ~1.5 cm of the conductive portion following the nostrils) are lined with a keratinised stratified squamous epithelium. Hairs, which filter large particulate matter out of the airstream, and sebaceous glands are also present.
At the transition from the vestibule to the respiratory region of the nasal cavity the epithelium becomes first stratified squamous and then pseudostratified columnar and ciliated. This type of epithelium is characteristic for all conductive passages dedicated to the respiratory system and therefore also called respiratory epithelium. Mucus producing goblet cells are present in the epithelium.
The surface of the lateral parts of the nasal cavity is thrown into folds by bony projections called conchae. These folds increase the surface area of the nasal cavity and create turbulence in the stream of passing air, both of which facilitate the conditioning (warming, cooling and filtration) of the air. Mucous and serous glands in the connective tissue underlying the epithelium, the lamina propria, supplement the secretion of the goblet cells. Veins in the lamina propria form thin-walled, cavernous sinusoids, also called cavernous bodies.
Tissues on the superior concha and the nasal septum form the olfactory region of the nasal cavity. Cilia in the epithelium of the olfactory region arise from olfactory cells. Although their internal structure resembles largely that of normal cilia they do not move, because they lack dynein arms which are necessary for cilial motility. The cell membrane covering the surface of the cilia contains olfactory receptors which respond to odour-producing substances, odorants, dissolved in the serous covering the epithelium. The axons of the olfactory cells collect into bundles in the lamina propria. The olfactory cells and their processes receive mechanical and metabolic support from supporting cells (or sustentacular cells). Basal cells can divide and differentiate into either olfactory or supporting cells.