Digestive System Lab Manual Flashcards
2 components of the oral cavity
teeth and tongue
components of “digestive tubes”
esophagus, stomach, small intestine, large intestine
accessory glands
salivary glands, liver, gall bladder, pancreas
the oral mucosa, aka the ___ ___ is composed of ____ ___ epithelium with an underlying loose connective tissue layer called ___ ____
the oral mucosa, aka the MUCOUS MEMBRANE is composed of STRATIFIED SQUAMOUS epithelium with an underlying loose connective tissue layer called LAMINA PROPRIA
the submucosa is aka the ___ ___. What does it contain?
RETICULAR LAYER. Contains blood vessels, neres, sensory receptors and lymphatics
3 different types of oral mucosa
lining mucosa, masticatory mucosa, specialized mucosa.
most of the oral cavity such as the cheeks, soft palate, lips, floor of tongue, alveolar surfaces etc. are lined with ___ mucosa and ___ ___. What kind of epithelium composes this type of mucosa?
most of the oral cavity such as the cheeks, soft palate, lips, floor of tongue, alveolar surfaces etc. are lined with LINING mucosa and LAMINA PROPRIA. Lining mucosa is composed of non-keratinized stratified squamous epithelium.
sense connective tissue ___ underlies the lamina properia
submucosa.
accessory salivary glands can be found in the ___ layer
submucosa.
in addition to accessory salivary glands, what kind of features are housed in the submucosa?
skeletal muscles such as the orbicularis oris surrounding the mouth.
where would you find masticatory mucosa?
in regions where abrasion due to chewing is most severe. Therefore, gums and inside of cheeks and HARD PALATE
what are gingivae
gums
Connective tissue ___ project into the base of the epithelium. Why?
PAPILLAE. anchors the lining mucosa’s epithelium to the LAMINA PROPRIA and prevents separation of the two layers.
Difference between the epithelium of masticatory and lining mucosa’s epithelium?
masticatory mucosa has keratinized epithelium (or parakeratinized when the cells retain their nuclei) and the papillae are deeper and more abundant than in lining mucosa. the masticatory mucosa has more papillae because it must resist more shearing forces associated with chewing.
What kind of adaptation does the lamina propria of masticatory mucosa have to provide further anchorage?
the lamina propria may have fibers to intertwine directly with the periosteum of the mandible to provide firm anchorage.
specialized mucosa is found on:
the tongues dorsal surface.
main functions of oral cavity
1) digestion of carbs/starch by saliva 2) mechanical digestion of food by breaking up by teeth to form bolus
baby teeth are aka
deciduous teeth
how many deciduous teeth
20
the 20 deciduous teeth are replaced by ___ permanent teeth
32
Discuss the distribution of adult teeth
2 incisors, one canine, two premolars, and three molars on each side.
portion of the tooth that projects above the gingivae
crown
the crown is covered by ___
enamel
what is enamel composed of?
95% calcium salts, 5% organic substacnes.
below the gumline, roots project into ___.
roots project into ALVEOLI (sockets) in the bone.
roots of a tooth are covered by ___
CEMENTUM.
TF: cementum contains haversian systems like normal bone
false. it does not have haversian systems and blood vessels like normal bone.
the fibrous ___ ___ connects the cementum with the alveolar bone and acts as its ___
the fibrous PERIODONTAL LIGAMENT connects the cementum with the alveolar bone and acts as its PERIOSTEUM
the constriction at the junction of the crown and roots is known as the __
neck
internally, the tooth consists of bone-like ___, and a ___ cavity. What are both components made of?
bone-like DENTIN (70% calcium salts) and a PULP CAVITY (loose connective tissue with NERVES of DENTAL PULP)
what nerves are located in the loose connective tissue of the pulp cavity?
dental pulp
the ____ is a mucous membrane that covers the bone tissue of the maxilla and mandible up to the tooth’s enamel. what epithelium is it composed of?
GINGIVA- a mucous membrane made of KERATINIZED stratified squamous epithelium.
How do baby teeth develop? Explain the process
from an invagination of thickened EMBRYONIC oral epithelium called the DENTAL LAMINA in each jaw. 1) dental lamina dilates and forms an enamel organ 2) in the enamel organ, mesenchyme begins to form the dental papilla. Enamel organ becomes CAP SHAPED and grows AROUND the dental papilla. 3) it now comprises continuous layers of epithelium: inner and outer enamel epithelium. 4) ameloblasts differentiate from the INNER enamel epithelium. 5) Odontoblasts form between ameloblasts and dental papilla, to secrete DENTIN 6) enamel organ continues to grow to form the crown. 7) connective tissue around the enamel forms the DENTAL FOLLICLE: precursor of the periodontal ligament and cementum 8) odontoblasts secrete dentin between the odontoblast and ameloblast layer
What is the precursor of the periodontal ligament?
Dental follicle, made from differentiated connective tissue around the enamel.
odontoblasts secrete ___ between the odontoblast and ____ layer
odontoblasts secrete dentin between the odontoblast and ameloblast layer
odontoblasts have cytoplasmic processes that stay in th dentin known as
dentinal tubules.
ameloblasts deposit ____ next to the dentin, which are secreted by:
depost ENAMEL next to the dentin, which are secreted by odontoblasts.
T/F: You can grow your enamel as an adult
false. ameloblasts die about the time a tooth erupts through the gum surface, and no new enamel can be formed.
How is skeletal muscle arranged in the tongue?
arranged in horizontal, transverse, and longitudinal bands.
what is in the between the muscle and epithelial (mucous) layers of the tongue?
LOOSE connective tissue LAMINA PROPRIA. Has occasional mucous and serous salivary glands.
Label
B= alveolar socket bone
GP= gingival pocket
P= pulp cavity containing dental pulp
D= dentin
E= ennamel
G= gingivae (gums) C= cementum (between dentin and periodontal ligament/bone)
BV= blood vessel
PL= periodontal ligaments.
periodontal ligaments are made of:
collagenous connective tissue. Collagen fibers are anchored in the cementum surrounding the dentin, and penetrate the cone as SHARPEYS FIBERS
T/F: periodontal ligaments are vascular
true.
4 types of papillae on the dorsal surface of tongue
1) filiform
2) fungiform
3) circumvallate
4) foliate
most keratinized type of tongue papillae. What is its function?
filiform papillae. Very keratinized and gives the tongue a grey coloration. Lacks taste buds. Has rough surface to assist in mixing of food during mechanical digestion
Why are fungiform papillae red?
because they have VERY little keratinized/not keratinized at all surfaece, making it relatively transparent. It is then very vascularized, so the blood vessels show up, giving it the characteristic red apparance.
which type of papillae contains the most taste buds? what kind of glands are present?
circumvallate papillae near the sulcus terminalis. Surrounded by a cleft where SEROUS VON EBNERS GLANDS drain.
3 types of cells of taste buds
1) gustatory cells (taste neuroepithelial cells)
2) support cells
4) basal cells
which cell of the tastebud is innervated? Which nerves are involved?
gustatory cells are innervated by the facial, glosopharyngeal, and vagus nerves
which cell of the tastebud produce the other type of taste bud cells
basal cells are STEM CELLS that produce both gustatory and support cells.
4 layers of the digestive tube walls (lumen to outside)
1) mucosa
2) submucosa
3) muscularis externa
4) serosa/adventitia.
which epithelium is the mucosa composed of? what is the lamina propria composed of?
mucosa is composed of stratified squamous epithelium. Deep to it is the lamina propria, which is made of VASCULAR LOOSE CONNECTIVE TISSUE.
the __ and ___ ___ form the mucous membrane of the gut. After the lamina propria lies the ___ ___, which is one or two thin layers of smooth muscle.
epithelium (stratified squamous) and lamina propria. after the lamina propria, there is a muscularis mucosae made of smooth muscle.BUT it is made of skeletal muscle in the PROXUMAL end of the ESOPHAGUS.
