Digestive System Flashcards
- derived from stomodeal ectoderm
- involved in prehension, mastication, ingestion and physical and enzymatic digestion
Digestive Organs
Adult fate of stomodeum?
Oral cavity
Adult fate of foregut?
Pharynx, esophagus, stomach
Cranial duodenum
Adult fate of midgut?
Caudal duodenum, jejunum, ileum, caecum, ascending colon, cranial half of transverse colon
Adult fate of hindgut?
Caudal half of transverse colon, descending colon and cloaca
Derivatives of oral cavity
lips, gums, teeth and tongue
Derivatives of cranial duodenum
Liver, gall bladder and pancreas
Derivatives of cloaca?
Rectum and part of anal canal
Derived from stomodeum and neural crest?
Teeth
Derived from stomodeum and pharynx
Tongue
Derived from stomodeum
Salivary glands
A thin membrane formed by fusion of the stomodeal ectoderm and pharyngeal endoderm
Oral plate
- forms the roof of the oral cavity
Hard palate
- with branched tubuloalveolar mucous or mixed palatine glands
T. submucosa of horse
- palatine bone
T. muscularis of hard palate
- separates the nasopharynx and oropharynx
Soft palate
- a mucotaneous junction between the skin and the mucous membrane of oral cavity
Lip
- thin skin with ordinary or sinus hair
- think hypodermis blends with skeletal muscle and fibroelastic c.t.
External surface or skin surface
- skin with no hairs, thin transparent epidermis that thickens toward the mucuous membrane
Transition zone or free margin
- mineralized structures embedded in the alveolar sockets of the lower and upper jaws
Teeth
- a type of teeth that stops growing after eruption
- present in carnivores and humans
Brachydont
- comprises most of the crown, the visible part of the tooth.
Enamel
- main bulk to the tooth that fills up the root, part of the crown and encloses the dental pulp
Dentin
- thin bone-like encrustation of the root immediately external to the dentin
Cementum
- sensitive part of the tooth located in the cavity of the dentin
Dental pulp
- columnar cells that line the inner surface of the cup
Ameloblasts
- Flat or columnar cells that covers the outer surface of enamel organ
outer epithelium of enamel organ
- loose aggregation of cells located between the inner ameloblast layer and outer epithelium of enamel organ
Stellate reticulum
Contains a mass of neural crest and mesenchymal cells from VA 1 (denral papilla)
Cavity of enamel organ
- outer columnar cells of dental papilla
- secretes dentin (outwardly)
Odontoblasts
- remaining cells of dental papilla
- invaded by blood vessels and nerves sensitive part of tooth
Dental pulp
- produce periodental ligament
Fibroblasts
- form alveolar bone
Osteogenic cells
- neck to roof
- form the cementum of tooth
Cementoblasts
- projects above the gum or gingiva
- one or more roots
- fits into the alveolar socket formed by alveolar bone
Erupted brachydont teeth
- expanded portion of the pulp cavity located in the crown, contains the dental pulp
Pulp chamber
- sensitive part of the tooth
- loose connective tissue
Dental pulp
- hardest substance in the body
- covers the dentine
Enamel
- forms the bulk of the tooth
Dentin
movable part of the tongue
Body