flashcards

where are Special sensory receptors located?

receptors are localized and cofined to the head region. they are not free ending of sensory nuerons but distinct receptor cells.

these are neuronlike epithelial cells or small peripheral neurosn that transfer sensory information to other neurons in afferent pathways to the brain.

special sensory receptors

sense of smell and taste receptors are classified as?

chemoreceptors

Taste buds

occur in the peglike projections of the tongue mucosa called papillae. Taste bubs occur within the epithelium that covers the papillae.

what are the two major cell types in a taste bud?

gustatory epithelial cells and basal epithelial cells. (long microvilli called gustatory hairs project from the gustatory epithelial cells and extend through a taste pore.

Name the sensory fibers carrying taste information ?

The facial nerve: transmits impulses from taste receptors in the anterior two-third of the tongue.

the glossopharyngeal nerve (lx) carries sensations fromt posterior third of the tongue.

The vagus nerve (x) carries taste impulses from the few taste buds on the epiglottis and lower pharynx.

Solitary nucleus.

part of the medulla where all gustatory neurons synapse and then are transmitted to the thalamus and ultimaly to the gustatory area of the cerebral cortex.

where do smell receptors lie?

in a pathc of epithelium on the roof of the nasal cavity. the receptors are part of the olfactory epithelium.

What are the only neuron that can undergo replacement?

the olfatory sensory neurons

where are the cell body of smell sensory neurons located?

They are found in the olfactory epithelium, a specialized tissue found in the roof of the nasal cavity.

cilia in the olfatory system

The olfactory cilia are tiny, hairlike extensions of sensory neurons located in the olfactory epithelium at the roof of the nasal cavity.

Their main function is to detect odor molecules in the air, allowing us to smell by binding odor molecules to receptors proteins located in the plasma membrane of the cilia.

filaments of the olfactory nerve

the olfatory sensory neuron’s axons gather into the nerve bundle called filaments fo the olfatory nerve. (cranial nerve i)

Mitral neuron cells

the cells to which the olfatory neurons synap after passing through the cribriform plate. these signal then get relayed to other parts of the brain.

The mitral cells sent impulses where?

1) the limbic region, where smelss elicit emotions

2) the primary olfactory cortex