EPIGLOTTIS
The epiglottis is a large, flat flap cartilage that controls entry to the trachea. During breathing, the epiglottis is in an upright position and keeps the entry to the trachea open. During swallowing, the epiglottis covers the entry to the trachea, redirecting food to the esophagus.
The thyroid, cricoid, and arytenoid cartilages are made of hyaline cartilage. The epiglottis, corniculate, and cuneiform are elastic cartilages.
OLFACTORY EPITHELIAL CELLS
Olfactory epithelial cells are modified neurons interspersed within the olfactory epithelium. The cell bodies of these olfactory neurons reside within the epithelium and have cilia that project onto the surface.
These cilia are not visible in the light microscope. The axons of these neurons extend to the olfactory bulb located within the cranial cavity.
GOBLET CELLS
The respiratory epithelium is primarily composed of ciliated columnar epithelial cells and interspersed with a number of goblet cells. Goblet cells are columnar epithelial cells (not ciliated) that produce and secrete mucus that is used to trap dust and pollen particles.
The cilia of regular epithelial cells beat in a constant sweeping motion, propelling the mucus and debris upwards toward the throat or the nasal cavity.
EPIGLOTTIS
The epiglottis is a large, flat flap cartilage that controls entry to the trachea. During breathing, the epiglottis is in an upright position and keeps the entry to the trachea open. During swallowing, the epiglottis covers the entry to the trachea, redirecting food to the esophagus.
The thyroid, cricoid, and arytenoid cartilages are made of hyaline cartilage. The epiglottis, corniculate, and cuneiform are elastic cartilages.
OLFACTORY EPITHELIAL CELLS
Olfactory epithelial cells are modified neurons interspersed within the olfactory epithelium. The cell bodies of these olfactory neurons reside within the epithelium and have cilia that project onto the surface.
These cilia are not visible in the light microscope. The axons of these neurons extend to the olfactory bulb located within the cranial cavity.
GOBLET CELLS
The respiratory epithelium is primarily composed of ciliated columnar epithelial cells and interspersed with a number of goblet cells. Goblet cells are columnar epithelial cells (not ciliated) that produce and secrete mucus that is used to trap dust and pollen particles.
The cilia of regular epithelial cells beat in a constant sweeping motion, propelling the mucus and debris upwards toward the throat or the nasal cavity.