Where are sensory epithelium, germinal epithelium, ciliated epithelium, and glandular epithelium found?

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ashley227 eNotes educator| Certified Educator

Sensory epithelium can be found in sense organs like the ear and nose. The sensory epithelium found in the cochlea (associated with hearing) give rise to the hair cells and supportive cells. It is these hair cells, when bent due to fluid vibrations in the inner ear, that transmit signals associated with sound to the brain. The sensory epithelium found in the nose (nasal epithelium) is just inferior to the cribriform plate of the ethmoid bone in the skull. It includes receptor cells that detect "odorants" and supportive cells. When an odorant is trapped in the mucous of the nasal cavity, the receptor cells are activated and send signals to the brain via the olfactory nerve.

Germinal epithelium can be found in the reproductive organs of males and females. In males, germinal epithelium lines the seminiferous tubules found in the testes and gives rise to mature spermatozoa. The germinal epithelium can also be found lining the ovaries of females. However, unlike in males, the germinal epithelium in females doesn't contribute to maturation of follicles containing oocytes (eggs).

Ciliated epithelium is located throughout the respiratory tract and in female fallopian tubes. In the respiratory tract (trachea and bronchi), the cilia attached to the pseudostratified columnar epithelium move mucus up toward the mouth and away from the lungs. The mucus is secreted by goblet cells in the epithelium and traps microbes and dust particles. The cilia are also responsible for movement in the female fallopian tubes. During ovulation a mature oocyte is released and drawn into a fallopian tube due to movement of fimbriae. Once in the fallopian tube, movement toward the uterus (where implantation occurs after fertilization) is due to the movement of the cilia.

Glandular epithelium is found throughout the body. Two types of glands are found in the body: endocrine and exocrine and they are all lined with glandular epithelium. Endocrine glands are associated with production and release of hormones, typically into the blood. Endocrine glands can be found in the pancreas, the thyroid, the anterior pituitary, the adrenal glands, and other organs in the body. Exocrine glands release their products through a duct and can be found in the skin (sweat glands), the pancreas (release digestive juices), and other parts of the body.