Transcript Chptrs.25-26

The Respiratory System
• Pulmonary ventilaton-movement of air in
and out of lungs;ventilation/breathing.
• External respiration-gas exchange between
blood and alveolar sacs.
• Transport of respiratory gasescardiovascular transport of oxygen/carbon
dioxide between lungs and tissue cells.
• Internal respiration
Functional Anatomy of the
Respiratory System
• Organs-Nose,nasal cavity,pharynx,larynx,
trachea, bronchi,smaller branches,
lungs,alveoli.
• Respiratory zone-respiratory
bronchioles,alveolar ducts,alveoli.
• Conducting zone-entrance, nasal
cavity,bronchioles.
The Nose and Paranasal Sinuses
• Nose provides: airway, moistens/warms entering
air,filters,speech resonating chamber,olfactory
receptors.
• External nose-nasal bones, maxillary bone, lateral
cartilage,greater & lesser alar cartilages,external
nares
• Nasal cavity-septum(septal cartilage,
perpendicular plate, vomer),conchae,meati,
respiratory epithelium
• Paranasal sinuses-frontal,sphenoid,
ethmoid,maxillary.
The Pharynx
• Connects nasal cavity and mouth to larynx
and esophagus.
• Nasopharynx, oropharynx, and
laryngopharynx
• Nasopharynx-posterior to nasal
cavity,inferior to sphenoid bone, superior to
soft palate level;auditory tubes
The Pharynx (cont’d)
• Oropharynx-lies posterior to oral
cavity;extends from soft palate to
esophagus; epithelium transitions from
pseudostratified to strat. squamous;
palatine, lingual tonsils
• Laryngopharynx-lies directly posterior to
epiglottis and extends to larynx
The Larynx
• Voice box extends 2 inches from C4-C6;attaches
to hyoid bone superiorly
• Functions in providing patent airway and to route
air and food into proper channels;voice
production.
• Laryngeal framework-thyroid cart., laryngeal
prominence,cricoid cart., arytenoid,
corniculate,cuneiform,vestibular fold,vocal
fold,epiglottis
• Laryngeal musculatureextrinsic(stabilization);intrinsic(regulate vocal fold
tension).
The Trachea
• Descends from larynx into mediastinum
• 10-12 cm (4 inches) long,2.5cm diameter(1
inch)
• Tracheal walls-mucosa, submucosa,
adventitia
• Trachealis muscle
• Carina
The Bronchi and Subdivisions:
The Bronchial Tree
The Conducting Zone
• Right/left primary bronchi(extrapulmonary)
• Secondary(lobar),tertiary(segmental),
terminal bronchioles
• Structural changes occur as bronchi
diameter diminish:(1)cartilage rings
replaced by irregular cartilaginous plates;
(2)pseudostratified>columnar>cuboidal;
and (3)smooth muscle increases.
The Bronchial Tree
The Respiratory Zone
• Terminal bronchioles feed into into
respiratory bronchioles.
• Alveolar ducts
• Alveolar sacs
Gross Anatomy of the Lungs
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Apex, base, root
Lobes: Superior, middle, inferior
Fissures:Horizontal,oblique
Surfaces: Costal, mediastinal, cardiac notch
Connective tissue, trabeculae, elastic
fibers, smooth muscles, and lymphatics.
Blood Supply and Innervation of
the Lungs
• Pulmonary arteries,arterioles, pulmonary
capillary network, venules, veins
• Bronchial arteries
• Pulmonary plexus-parasympathetic motor,
visceral sensory fibers
The Pleurae
• Parietal
• Visceral
• Pleural cavity
Respiratory Muscles
• Diaphragm
• External,internal intercostal
• Accessory muscles:
Sternocleidomastoid,serratus anterior,
pectoralis minor, scalenes (inspiration)
Respiratory Muscles (cont’d)
• Accessory muscles:external/internal
intercostals, abdominal obliques, and rectus
abdominis(expiration)
Respiratory movements:
• Eupnea (diaphragmatic breathing/costal
breathing)
• Hyperpnea
Respiratory membrane
• Type I cells (epitheliocytes)-alveolar walls;
angiotensin converting enzyme(ACE)
• Type II cells-secrete surfactant (interferes
w/H20 molecule cohesiveness
• Alveolar macrophages
• Respiratory membrane-fused basal laminas
of alveolar epithelium & capillary
endothelium
Pulmonary Ventilation
• Inspiration-diaphragm,intercostals
• Expiration-quiet vs. forced
Medullary Respiratory Centers
• Dorsal respiratory group-root of Cn
IX;pacesetting; inspiratory center
• Ventral respiratory group-extends within
ventral brain stem to pons-medulla
junction;forced breathing
• Pons respiratory centers-fine tunes
inspiration/expiration transition;deters
overinflation
Pathologies
Chronic Obstructive Pulmonary Disease
• Obstructive emphysema-alveolar
enlargement,alveolar wall deterioration
• Chronic bronchitis-inhaled irritants
• Asthma
• Tuberculosis
• Lung Cancer
Digestive System
• Alimentary canal(digestion/absorption)mouth, pharynx,esophagus, stomach, small
intestine,large intestine.
• Accessory organs-teeth, tongue,salivary
glands, gall bladder,liver, and pancreas.
Digestive Process
• Ingestion
• Propulsion
• Mechanical digestion
• Chemical digestion
• Absorption
• Excretion
* Digestive lining protects against corrosive effects
of enzymes/acids,abrasions, and pathogens.
Mesenteries
• Fused double sheets of peritoneal
membrane;provides routes for blood
vessels, lymphatics, and nerves.
• Organ reinforcement, prevent
entanglement
• Lesser/greater omentum,
mesocolon(transverse,sigmoid)
• Retroperitoneal(pancreas,large
intestine);intraperitoneal(stomach)
Histological Organization
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Mucosa
Submucosa
Muscularis externa
Serosa
The Mucosa and Submucosa
• Mucus secretion, absorption, protection
• Submucosa-loose CT surrounding
muscularis mucosae;contains
blood/lymphatic vessels,nodules, nerve
fibers.
Muscularis Externa
• Responsible for peristalsis/segmentation
• Circular(inner)layer,longitudinal(outer)lay
er-sphincters
• Myenteric plexus (of Auerbach)
The Serosa
• Protective outermost layer of
intraperitoneal organs(visceral
peritoneum);areolar CT; pharyngeal,
esophageal,rectal serosa replaced by
adventitia (fibrous CT)
Peristalsis/Segmentation
• Peristaltic wave-rhythmic contractions of
circular and longitudinal muscles;
pacesetter cells
• Segmentation-churn and fragment
digested materials;circular contractions
Functional Anatomy of the Digestive
System
Oral Cavity
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Bounded by lips, cheeks, palate, tongue
Vestibule, labial frenulum
Hard/soft palate(uvula)
Palatopharyngeal, palatoglossal arches
• Tongue;dorsum with papillae;frenulum
The Teeth
• Primary(deciduous),permanent dentitions
• Incisors,canines, premolars, molars
• Formula: 2I, 1C, 2PM,3M x 2 =32
2I, 1C, 2PM,3M
• Structure:Enamel,dentin, pulp cavity, root
canal,periodontal ligament, cementum,
gingival sulcus.
Salivary Glands
• Saliva: 99% water +buffers, metabolites,
enzymes.
• Saliva cleanses mouth, moistens/dissolves
food.
• Extrinsics: parotid, submandibular,
sublingual; intrinsics: buccal
The Pharynx
• Pharyngeal constrictors-initiates bolus
movements
• Palato/Stylopharyngeus-elevate larynx
• Palatal muscles-raise soft palate & portions
of pharyngeal wall
• Swallowing process/phases: buccal,
pharyngeal, esophageal
The Esophagus
• Hollow, muscular tube:25 cm.long,2 cm
diameter
• C6 to T7
• Angiology: esophageal,thyrocervical trunk,
external carotids, bronchials, celiac trunk &
inferior phrenic artery
• Innervation: Vagus & esophageal plexus
The Esophagus (cont’d)
• Mucosal stratified epithelium
• Esophageal glands
• Superior 1/3 has skeletal muscles fibers,
middle third has skeletal/smooth
mixture;bottom third has smooth;visceral
reflexes
• No serosa
The Stomach
• Stomach functions in: storage of ingested food,
mechanical breakdown, and chemical
digestion(chyme formation).
• T7-L3
• 15-25 cm long; empty(50ml),full(up to 4L).
• Rugae
• Cardia, body, fundus, lesser/greater curvatures
• Pylorus, sphincter.
The Stomach (cont’d)
• Angiology: left gastric (lesser curve & cardia),
splenic(fundus & greater curve),common
hepatic(lesser/greater curves of pylorus)
• Innervation:Thoracic splanchnic
nerves(sympathetic fibers) from celiac
plexus;parasympathetics supplied from vagus
nerve.
• Musculature:circular, longitudinal
Stomach Histology
• Gastric pits/glands
• Gastric glands have three cell types:(1)
parietal-HCL/intrinsic factor;(2) chiefpepsinogen, rennin/gastric
lipase(newborns);(3) enteroendocrinegastrin
The Small Intestine
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Body’s major digestive organ
6m long, 4cm-2.5 cm diameter
Accounts for 90% of nutrient absorption
Plicae circulares
Three subdivisions: duodenum, jejunum,
ileum
Small Intestine (cont’d)
• Duodenum is retroperitoneal; (L1-L4)
• Hepatopancreatic ampulla and sphincter,
major duodenal papilla.
• Jejunum;2.5 m long
• Ileum(peritoneal);3.6m long;ends at valve
Intestinal Histology
• Intestinal villi-contain lacteals,
microvilli,enterocytes
• Intestinal crypts-secrete intestinal juice
• Peyer’s patches -lymphoid follicles found
in submucosa
• Brunner’s glands-occur in duodenal
submucosa
Large Intestine
• Frames small intestine on three sides and
extends from ileocecal valve to anus
• 1.5m long
• Functions:(1) resorption of water/
electrolytes;compaction of feces(2)vitamin
absorption(bacterial flora)
Large Intestine (cont’d)
• Cecum,vermiform appendix
• Colon:haustra,taenia coli, epiploic
appendages
• Colon regions:Ascending>hepatic
flexure>transverse>splenic
flexure>descending>sigmoid
flexure>sigmoid
• Rectum: Anal canal/ columns,
internal/external anal sphincter, anal orifice.
The Liver
• Largest visceral organ
• Functions:metabolic/hematological
regulation, bile production.
• Falciform ligament,ligamentum teres, lobes
(right,left,caudate, quadrate),porta hepatis
• Angiology: hepatic artery proper,portal vein
Liver Histology(cont’d)
• Lobules(central vein),hepatocytes
• Portal triad:hepatic artery branch, portal
vein branch, bile duct
• Sinusoids(hepatic macrophages)
Gall Bladder
• Stores/modifies bile
• Fundus, body, neck
• Cystic duct
The Pancreas
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Exo/endocrine gland
Head, body, tail
Retroperitoneal
Pancreatic/accessory pancreatic duct
Exocrine product-pancreatic juice
Islets of Langerhans