Flashcards in Anatomy- how do we taste, chew and swallow? Deck (91)
What are the four muscles of mastication?
Specify which of these are jaw opening and jaw closing muscles.
Jaw closing: masseter, temporalis, medial pterygoid
Jaw opening: lateral pterygoid
What is the origin and insertion of the masseter?
The angle of the mandible and the zygomatic arch/zygoma.
What is the origin and insertion of the temporalis?
The coronoid process of the mandible and the lateral aspect of the neurocranium
What is the origin and insertion of the medial pterygoid?
The Medial side of the angle of the mandible
The pterygoid plates of the sphenoid bone
What is the origin and insertion of the lateral pterygoid?
The condyle of the mandible
The pterygoid plates of the sphenoid bone
What supplies the muscles of mastication?
The mandibular division of the trigeminal nerve (CNV3)
What are the muscles of facial expression?
A group of skeletal muscles, attaching between bones of the face and the superficial fascia just deep to the skin of the face.
What supplies the muscles of facial expression?
Cranial nerve VII (facial nerve)
What is the name of the circular muscle which encircles the lips?
What does it do?
Orbicularis oris. It creates a seal that prevents dribbling during chewing and swallowing.
What type of epithelium lines the oral cavity? Which parts of the epithelium are keratinised?
Stratified squamous epithelium
The epithelium lining the gingivae and the hard palate are keratinised for their protection during swallowing.
Why does the mucosa in the oral cavity appear pinker than skin?
Because it is very vascular.
How is the mucosa in the oral cavity named?
Name all the different parts.
It is named according to the area of the oral cavity it covers.
I.e. palatal mucosa, lingual mucosa, mucosa of the floor of the mouth, buccal mucosa and labial mucosa.
What are the parts of the oral cavity from which the teeth protrude named?
The upper and lower dental arches
Why is the mouth the most sensitive body area?
There is a large number of sensory receptors in the oral mucosa and there is a large area of brain dedicated to interpreting sensory signals from the mouth area.
What are the general sensations felt by the mouth?
Which nerve is responsible for these?
Pain, temperature, touch and proprioception.
Cranial Nerve V (trigeminal)
What is the special sensation sensed by the mouth?
Which nerves transmits these impulses?
Taste is the special sensation of the mouth.
Cranial nerves VII and IX (facial and glossopharyngeal)
What is the tongue made of?
Which nerve supplies it?
It is made of skeletal muscle and is supplied by CN XII (hypoglossal nerve)
What structures cover the tongue?
What are their functions?
Some papillae give surface texture which helps the tongue manipulate food.
Some papillae have the function of taste.
Which part of the tongue is in the oral cavity?
The anterior 2/3, which is the horizontal part of the tongue.
Where is the posterior 1/3 of the tongue located?
In the oropharynx
Which papillae have taste buds?
Which cranial nerves are they supplied by?
The foliate papillae, the valate papillae and the fungiform papillae.
They are supplied by cranial nerves VII and IX (facial nerve and glossopharyngeal nerves)
Which papillae do not have taste buds and just have general sensations?
Which cranial nerve are they supplied by?
CN V (trigeminal)
How is the tongue suspended in position?
By four pairs of skeletal muscles called the extrinsic muscles of the tongue. These muscles attach at one end to structures outwith the tongue and insert at the other end into the tongue.
How is the shape of the tongue modified?
By four pairs of skeletal intrinsic muscles of the tongue.
What muscle in the cheek is closely related to the orbicularis oris?
What nerve supplies this muscle?
What is the function of this muscle?
It is supplied by cranial nerve VII.
With the help of the tongue, it acts to position the food bolus between the occlusal surfaces of the premolar and molar teeth for mastication.
Where do the external muscles of the tongue originate from?
The styloid process of the temporal bone, the hard palate, the hyoid bone and the mandible.
How many teeth does an adult have?
How are they arranged?
32. They are in 4 quadrants (upper and lower right and left).
The teeth in each quadrant is number 1-8.
1-2 = incisors
4-5 = premolars
6-8 = molars ( 8 are the wisdom teeth).
What are the salivary glands classified as?
Accessory organs of the upper GI tract
What does saliva contain?
Water (99%)- solute to allow tasting to occur
Mucin- a lubricant to aid speech and swallowing and for keeping the mucosa moist
Buffer- for plaque acids
Amylase to begin CHO digestion