The hearing and equilibrium system of the body. It consists of three parts

The hairs which project from the edges of the EYELIDS.

A specialized structure that serves as an organ of the sense of smell as well as part of the respiratory system; the term includes both the external nose and the nasal cavity.

Cartilage of the EAR AURICLE and the EXTERNAL EAR CANAL.

A tiny muscle that arises from the posterior wall of the TYMPANIC CAVITY of MIDDLE EAR with its tendon inserted onto the neck of the STAPES. Stapedius pulls the stapes posteriorly and controls its movement.

The muscles that move the eye. Included in this group are the medial rectus, lateral rectus, superior rectus, inferior rectus, inferior oblique, superior oblique, musculus orbitalis, and levator palpebrae superioris.

A short muscle that arises from the pharyngotympanic tube (EUSTACHIAN TUBE) and inserts into the handle of the MALLEUS. This muscle pulls the handle medially thus controlling the tension and movement of TYMPANIC MEMBRANE.

Small sensory organs which contain gustatory receptor cells, basal cells, and supporting cells. Taste buds in humans are found in the epithelia of the tongue, palate, and pharynx. They are innervated by the CHORDA TYMPANI NERVE (a branch of the facial nerve) and the GLOSSOPHARYNGEAL NERVE.

That portion of the nasal mucosa containing the sensory nerve endings for SMELL, located at the dome of each NASAL CAVITY. The yellow-brownish olfactory epithelium consists of OLFACTORY RECEPTOR NEURONS; brush cells; STEM CELLS; and the associated olfactory glands. Vomeronasal Organ;

Neurons in the OLFACTORY EPITHELIUM with proteins (RECEPTORS, ODORANT) that bind, and thus detect, odorants. These neurons send their DENDRITES to the surface of the epithelium with the odorant receptors residing in the apical non-motile cilia. Their unmyelinated AXONS synapse in the OLFACTORY BULB of the BRAIN.

A specialized part of the olfactory system located anteriorly in the nasal cavity within the nasal septum. Chemosensitive cells of the vomeronasal organ project via the vomeronasal nerve to the accessory olfactory bulb. The primary function of this organ appears to be in sensing pheromones which regulate reproductive and other social behaviors. While the structure has been thought absent in higher primate adults, data now suggests it may be present in adult humans.

INTERNEURONS of the vertebrate RETINA. They integrate, modulate, and interpose a temporal domain in the visual message presented to the RETINAL GANGLION CELLS, with which they synapse in the inner plexiform layer.

INTERNEURONS of the vertebrate RETINA containing two processes. They receive input from the VERTEBRATE PHOTORECEPTORS and send output to the RETINAL GANGLION CELLS. The bipolar cells also make lateral connections in the retina with the RETINAL HORIZONTAL CELLS and with the AMACRINE CELLS.

Cells specialized to detect and transduce light.

One of the two photoreceptor cell types of the vertebrate retina. In rods the photopigment is in stacks of membranous disks separate from the outer cell membrane. Rods are more sensitive to light than cones, but rod mediated vision has less spatial and temporal resolution than cone vision.

The portion of the retinal rod cell between the inner segment and the pigment epithelium layer of the retina.

One of the two photoreceptor cell types in the vertebrate retina. In cones the photopigment is in invaginations of the cell membrane of the outer segment. Cones are less sensitive to light than rods, but they provide vision with higher spatial and temporal acuity, and the combination of signals from cones with different pigments allows color vision.

A highly vascular ovoid body of chemoreceptive tissue lying adjacent to the TYMPANIC CAVITY. It is derived from NEURAL CREST tissue and is considered part of the diffuse neuroendocrine system. It is the site of a rare neoplasm called a GLOMUS TYMPANICUM TUMOR.