Internal Organs Flashcards
1
Q
Oral Cavity
A
- divided into vestibule and oral cavity proper
- vestibule: part lying between lips and cheeks, and the teeth. In it the canal of the parotid gland is opened at the level of the upper 2nd molar tooth
- oral cavity proper: bound by hard and soft palates superiorly, and the tongue and floor of the mouth inferiorly; the entrance of the oropharynx posteriorly. Ducts of submandibular and sublingual empty
- lymphatic tissue which surrounds the oropharynx:
- palatine tonsils
- lingual tonsils
- pharyngeal tonsils
- tubal tonsils
2
Q
Lip (labium)
A
- core of striated muscle (m. orbicularis oris) embedded in fibroelastic CT
- outer surface covered with skin- stratified squamous keratinised, containing many hair follicles and sebceous glands, and sweat glands
- red transitional zone between outer skin and inner mucous membane
- inner surface covered with mucous membrane and is stratified squamous nonkeratinised. Labial glands seen
3
Q
Hard Palate
A
- containing bone, bisected into right and left halves by raphe
- anteriory the hard palate contins fatty tissue in the submucosa, posteriorly there are mucous glands
- The maxillary nerve branch of the trigeminal nerve supplies sensory innervation to the palate.
4
Q
Soft Palate
A
- posterior border in the midline: uvula
- two folds: palatoglossus and palatopharygeus; between them palatine tonsils
- muscle fibres:
- m. palatoglossus
- m. palatopharyngeus
- m. tensor veli palatini
- m. levator veli palatini
- m. uvulae
- The tensor veli palatini is innervated by the medial pterygoid nerve, a branch of mandibular nerve, the third branch of the trigeminal nerve (CN V) - the only muscle of the palate not innervated by the vagus nerve.
- the mucous membrane lining the oral surface is stratified squamous nonkerat. The pharyngeal surface is pseudostrat cilliated columnar
5
Q
Tongue
A
- mucous membrane of upper surface us divided into anterior two thirds (corpus linguae) and posterior pharyngeal part (radix linguae). Divided by sulcus teminalis; the apex of this sulcus projects back to a small pit (foramen cecum)
- 4 types of papillae:
- filliformes: most numerous and smallest, keratinised stratified without taste buds
- fungiformes: on dorsal surface, mostly at the apex. Taste buds present in the covering strat squam nonkerat
- vallatae: 10 to 12 in number, in a row immediately in front of sulcus terminalis. Surrounded by moat-like invagination lined with nonkerat strat squam that contains numerous tastebuds. Von Ebners glands (lingual salivary) emty their serous secetions andflush material from the moat.
- folliatae: parallel low ridges separated by deep mucosal clefts, aligned at right angles to the longitudinal axis of the tongue. Occur on lateral edge of tongue. May not be recognised in aged humans. Taste buds
- mucosa of the pharyngeal part of the dorsum contains many lymphoid follicles that form the lingual tonsils in the lamina propria
- muscles: intrinsic and extrinsic
6
Q
Salivary Glands
A
- minor salivary glands:
- labial, lingual, buccal, palatine
- located in submucosa
- empty directly into cavity via short ducts
- major salivary glands:
- paired parotid, sublingual and submandibular
- surrounded by a capsule of moderately dense CT
- acini of salivary glands contain either serous cells (protein secreting), mucous cells (mucin secreting) or mixed
- serous acini:
- spherical
- nuclei centrally located
- secretory zymogen granules
- mucous acini:
- tubular in shape
- mucous cells are polyhedral in shape and surround a large lumen
- flat nuclei, basally located
- mixed acini:
- cap of serous cells that secrete into a highly convoluted intercellular space lumen. called serous demilunes
- lumen of salivary acinus:
- continuous with that of a duct system, having 3 sequential segments; intercalated duct, striated, excretory. All with cuboidal epithelium
7
Q
Glandula Parotis
A
- largest pair of salivary glands
- below external acoustic meatus, between mandible and sternocleidomastoid
- duct opens oposite 2nd uper molar
- surounded by fibrous capsule, septa divide into lobes and lobules
- secretory portion is tubulo-alveolar serous acini
- serous cells roughly cuboidal or pyramidal in shape
8
Q
Glandula Sublingualis
A
- below the floor of the mouth, anterior to submandibular glands
- secretions enter by 8 to 20 short ducts
- not surrounded by fibrous capsule
- mucous and serous, mostly mucous acini
9
Q
Glandula Submandibularis
A
- below the floor of the mouth, beneath the body of the mandible
- ducts open on either side of the frenulum of the tongue, just behind the lower incisor teeth
- surrounded by fibrous capsule. Almost no adipose tissue within the gland
- mucous and serous types, mostly serous
10
Q
Histological Structure of Alimentary Canal
A
-
tunica mucosa:
-
lamina epithilialis: separates the lumen of the digestic tract from the body of the organism. Synthesises and secretes digestive enzymes, hormones, mucus, antibodies.
- in the oesohagus, stratified quamous nonkeratinised
- small intestine, simple columnar
- anal part of rectum: strat squam nonkera
- lamina propria: often rich in elastic fibres. provides nutrient vessels, glands, GALT, growth factors
- lamina muscularis mucosae: boundary between mucosa and submucosa. inner circular and outer longitudinal layer can b distinguished
- lamina submucosa: strongest layer, bundles of collagen. also contains the largest arterial network of the wall. submucosal plexus (of Meissner) is a network of symp and paasymp nerves
-
lamina epithilialis: separates the lumen of the digestic tract from the body of the organism. Synthesises and secretes digestive enzymes, hormones, mucus, antibodies.
- tunica muscularis: distinct inner circular and outer longitudinal layers. Create waves of peristalsis. Myenteric (auerbachs) plexus lies between circular and long layers
-
serosa and adventitia:
- the serosa is part of the visceral peritoneum that attaches the organs to the abdominal wall. consists of thin CT layer (lamina subserosa) covered by mesothelium (simple squamous)
- the portions of the digestive tract that do not possess a serosa are attached by a loose CT, the adventitia. Blends with general CT of adjoining structures
11
Q
Pharynx
A
- musculomembranous tube extending from the base of the skull to 6th cervical vertbrae, where it becomes continuous with the oesophagus
- 3 parts:
- nasopharynx
- oropharynx
- laryngopharynx
- auditory eustachian tubes connect nasopharynx to each middle ear
- pharyngeal tonsils at posterior wall of nasopharynx
- tubal tonsils near opening of eustachain tubes
- pharynx has a musculomembranius wall that is deficient anteriorly. Replaced by:
- posterior nasal apertures
- oropharyngeal isthmus
- inlet of the larynx
- wall has 3 layers:
- mucous
- fibrous
- muscular
- part of pharynx susceptible to abrasion: nonkeratinised stratified squamous (continuous with oral cavity and oesophagus)
- respiratory portion has pseudostrst cilliated columnar
- muscular layer consists of superior, middle and inferior constrictors, stylopharyngeus, palatopharyngeus, salpingopharyngeus (levator muscles, fibres run longitudianlly)
12
Q
Oesophagus
A
- 25cm long
- pharynx to stomach
- cervical, thoracic and abdominal part
- anatomical constrictions:
- at its commencement 15 cm from incisors
- where crossed by left principle bronchus (27.5 cm)
- as it transverses the diaphragm (40 cm)
- 2 physiological constrictions:
- where crossed by aortic arch (22.5 cm)
- as it enters the stomach
- wall consists of 3 layers:
- mucous membrane
- muscular coat
- adventitia
- lamina epithilialis starts off as strat squam nonkerat, then becomes simple columnar
- lamina propria: oesophageal cardiac glands
- tunica muscularis: upper third is straited muscles, in the middle the straited nd smooth muscle are interwoven; distal third is smooth muscle
- tunica adventitia, until oesophagus enters abdominal cavity where it is covered by serosa
13
Q
Stomach
A
- 2 surfaces:
- anterior and posterior, lesser and greater curvatures
- 2 orifices: cardiac and pyloric
- intraperitoneal
- fundus: usually full of gas
- body: extends from level of cardiac orifice to the level of incisura angularis
- pyloric antrum: from incisura angularis to the proximal limit of the pylorus. Pylorus is the most tubular part; it’s thick muscular wall forms the pyloric sphincter
- cavity of pylorus is called the pyloric canal
- stomach lining thrown into longintudinal folds called rugae, prominent in the lower regions
- at higher magnifications, numerous openings called foveolae (gastric pits), into the bottom of which open 3 to 7 tube shaped gastric glands
- glands: cardiac, pyloric and fundic or gastric
- each gland has neck, body and bottom
- glands of the fundus and body:
- chief or peptic: pepsinogn and a weak lipase
- parietal or oxintic: produce HCl and intrinsic factor
- mucous neck cells
- argentaffin: enteroendocrine
- undfferentiated: stem cells
- cardiac glands: secrete mucous
- pyloric glands located in pyloric antrum, enteroendocrine and occasional parietal cells
- gastric tunica muscularis:
- outer long
- middle circular
- inner oblique
- auerbachs plexus innervates them
14
Q
Small Intestine
A
- extends from pylorus to ileocecal junction
- duodenum: 25 cm
- jejunum: 2.5 m
- ileum: 3.5 m
- principal site for digestion and absorption
- simple columnar, absorption and reabsorption. Microvilli present
- plicae circulares; permanent transverse folds. Becme reduced in size and number in the middle of the ileum
- cells:
- absorptive cells
- goblet cells
- argentaffin cells
- paneth cells: evidence that they secrete lysozyme
15
Q
Duodenum
A
- superior part (intraperi), decending, horizontal, ascending (all retroperi)
- submucosa contains Brunners glands; secrete watery fluid rich in bicarbonate, which hel neutralise the acid secretions of the stomach
19
Q
Liver
A
- lobes:
- right lobe:
- right
- caudate
- quadrate
- left lobe
- right and left lobe may be separated by:
- fissure for ligamentum teres
- fissure for ductus venosus
- right lobe:
- situated in right hypochondriac region, 1.5 kg, intraperitonesl apart from area nuda
- functional blood supply from portal vein
- nutritional blood supply from hepatic artery
- covered by thin CT capsule of Glisson that becomes thicker at the hilum (porta hepatis)
- porta hepatis: portal vein, hepatic artery, common bile duct (common heptaic duct from right and left, and cystic)
- ligaments:
- falciform: left triangular and coronary ligament which becomes right triangular lig (area nuda)
- teres
- venosum
- lesser omentum
- portal triads:
- 6 triads per lobule
- venule from portal vein
- arteriole from hepatic artery
- bile duct
- lymphatic vessels
- lobules:
- central vein
- hepatocytes
- 6 triads
- liver sinusoids
- space of disse separating endothelial cells from underlying hepatocytes
- Kupffer phagocytic cells
- fat storing Ito cells in SoD
24
Q
Larynx
A
- muscles:
- intrinsic:
- cricothyroid
- cricoarytenoid: posterior and lateral
- arytenoid: transverse and oblique
- thyroarytenoid
- all innervated by recurrant laryngeal branch of vagus; apart from cricothyroid which is innervated by external laryngeal branch of superior laryngeal nerve
- extrinsic:
- sternothyroid
- omohyoid
- sternohyoid
- inferior constrictor muscles
- thyrohyoid
- digastric
- stylohyoid
- myohyoid
- geniohyoid
- hyoglossus
- genioglossus
- intrinsic:
- irregularly shaped hyaline cartilages: paired and unpaired;
- paired: aytenoid, coniculate and cuneiform
- unpaired: cricoid, throid and epiglottis
- lined by mucous membrane, on each side are the vocal ligaments; ligaments produce vocal folds. the gap between the vocal folds is called the rima glottidis
- stratified squamous epith on oral side, and pseudostat cilliated columnar on respiratory side
