DSA Neuroanatomy of Gustation & Olfaction Flashcards
Via _______ _______ neurons, humans can recognize thousands of airborne odors, many at extremely low concentrations. This plays a role in the pleasure associated with eating and helps us recognize environments.
Olfactory receptor
The bones of the nasal cavity are very (THICK/THIN). This makes the olfactory receptor neurons very sensitive to facial trauma.
Thin
The taste system has a very limited range of sensation. The four basic tastes are…
Sweet
Salty
Sour
Bitter
Umami sensation may be important for the identification of…
Amino acids
T/F. The combinations of taste qualities are important in acceptance or rejection of foods.
True
What can recognize a wider variety of sensations?
A. Tongue
B. Nose
C. They are the same
B. Nose
How are we able to recognize different tastes other than the 4 basic ones?
A. There are thousands of types of taste receptors.
B. Few taste receptors in different combinations result in different taste sensations.
C. I have no idea.
B. Few taste receptors in different combinations result in different taste sensations.
1.5 yo male presents with a cold. Their parent reports they are completely stopped up. The parent also reports that the child put coffee beans in their mouth and did not spit it up. Why?
A. Young children put stuff in their mouth all the time.
B. The child obviously likes coffee.
C. Olfaction and taste are intimately related.
C. Olfaction and taste are intimately related.
This is a critical anatomical structure that helps humans smell. It lies in the cribriform plate of the ethmoid bone.
Olfactory Bulb
This helps transmit sensory information from the environment to the brain.
Olfactory Tract
The olfactory bulb sits here. This is the rostral end of the olfactory sulcus and the rostral portion of the anterior cranial fossa.
Cribriform Plate
These neurons are located on the roof of the nasal cavity. They are located on the inferior surface of the cribriform plate, along the nasal septum, and on the medial wall of the superior turbinate (concha).
Olfactory Receptor Neurons
The Olfactory Receptor Neuron is CN 1. It has a single _______ _______ that receives information from the environment. These receptors are found in olfactory mucosa of the superior portion of the nasal cavity.
Dendritic process
This is what keeps the nasal cavity moist.
Ducts and glands within the olfactory epithelium
Olfactory nerve bodies are surrounded by _________ cells. The dendrites and receptors of these cells will extend into the olfactory epithelium where they will have good exposure to smell molecules.
Supporting
The cilia of an Olfactory Receptor Neuron are _________ and contain _________ receptors.
Non-motile
Odorant
What type of receptors are odorant receptors?
GPCRs
An odorant receptor is activated by a ligand odor molecule binding to its specific GPCR. This causes a signal to be sent from the Olfactory Receptor Neuron to the…
Olfactory Bulb
This layer of CT holds lots of immune cells. This is important because the mucosa is directly exposed to the external environment.
Lamina Propria
These cells are just superficial to the basement membrane. These act as stem cells for Olfactory Receptor Neurons and supporting cells. They continuously turn over and as a result, most cells in the olfactory mucosa have a life span of 30-60 days.
Basal cells
The cell bodies of Olfactory Receptor Neurons lie in one layer, while their single dendrite extends to the ________ layer. The axons travel up to the olfactory bulb through the _______ _______.
Mucus
Lamina Propria
These cells offer physical and metabolic support to the surrounding cells in the olfactory mucosa.
Supporting/Sustentacular cells
These are ciliated columnar epithelial cells in olfactory mucosa.
Brush Cells
This is made and secreted by the glands and ducts in the Olfactory Epithelium.
Mucus
What are the layers of the olfactory mucosa?
Lamina Propria Basal Cells Olfactory Receptor Neurons (cell bodies) Supporting/Sustentacular cells Brush cells Cilia Mucus
Describe the process of smell.
At the back of the nasal cavity is olfactory epithelium that has olfactory receptors (GPCRs). We breathe in, and odorant molecules get trapped in mucus and bind to these receptors. This activates the neurons and send a signal through the olfactory bulb, then olfactory tract and into your brain.
***We can distinguish between odors because one odor will bind to certain olfactory receptor neurons, while another odor will bind to different neurons.
Smell molecules are transmitted into sensory information when they act as a ligand and interact with the GPCR of an Olfactory Neuron Receptor. Initially, the smell molecule will contact the ________ layer that covers the Olfactory Epithelium. There it will interact with odorant-binding proteins.
Mucus
The smell molecule acts as a ligand and binds a GPCR. This activates _______ ______ which results in an increase in _______.
Adenylyl Cyclase
cAMP
After smell molecules have lead to the increase in cAMP, cAMP binds ion channels which leads to an increase in _______ and _______ influx into the cell. This causes a depolarization and an action potential. The action potential travels up the Olfactory Receptor Neuron where it synapses with neurons in the ________ ________.
Calcium
Sodium
Olfactory Bulb