respiratory system
DESCRIPTION
RESPIRATORY SYSTEM. Dr Iram Tassaduq. INTRODUCTION. The respiratory system consists of paired lungs and a series of air passages that lead to and from the lungs. PORTIONS OF RESPIRATORY SYSTEM. Air passages of respiratory system consist of two portions Conducting portion - PowerPoint PPT PresentationTRANSCRIPT
RESPIRATORY SYSTEM
Dr Iram Tassaduq
INTRODUCTIONThe respiratory system consists of
paired lungs and a series of air passages that lead to and from the lungs
PORTIONS OF RESPIRATORY SYSTEM
Air passages of respiratory system consist of two portionsConducting portion Respiratory portion
FUNCTIONSAir conductionAir filtrationGas exchangeSpeech productionImmune responseEndocrine function
NASAL CAVITYNasal cavities are
paired chambers separated by bony and cartiliginous septum.
Chambers are divided into 3 regions
VestibuleRespiratory segmentOlfactory segment
VESTIBULESThe 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
RESPIATORY SEGMENT 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.
CELLS OF RESPIRATORY SEGMENT
•Ciliated cells•Goblet cells •Brush cells•Small granule cells•Basal cells
CELLS OF OLFACTORY EPITHELIUM
FUNCTIONS OF OLFACTORY EPITHELIAL CELLS OLFACTORY CELLS 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
SUSTENTACULAR CELLS . The olfactory cells and their processes receive
mechanical and metabolic support from supporting cells BASAL CELLS can divide and differentiate into either olfactory or
supporting cells. BRUSH CELLS Columnar cells with microvilli and are specialized for
transduction of general sensation
The supporting cells and the secretion of the serous glands contain lipofuscin granules, which give a yellow-brown colour to the surface of the olfactory region.
OLFACTORY GLANDS
The wall of the Larynx consists of :MucosaPoorly defined submucosaA series of irregularly shaped cartilages connected by joints of relatively dense fibroelastic tissue.A group of intrinsic skeletal muscles which act upon the cartilages.
LAYERS OF LARYNX
Short, flexible, air tube 2.5 cm 10 cm long Extent Function
TRACHEATypical respiratory epithelium -The lamina propria - contains large
amounts of elastin and aggregates of lymphoid tissue (BALT).
The submucosa - contains mucous glands.
C-shaped rings of hyaline cartilage - provide a semirigid supporting skeleton outside the submucosa to prevent collapse of the airway during inspiration.
The adventitia - outermost fibroelastic connective tissue layer.
TRACHEAL EPITHELIUM
CELLS OF RESPIRATORY EPITHELIUM
BRUSH CELL
SMALL GRANULE CELL
LAYERS OF TRACHEA
LAYERS OF TRACHEA