Final Exam Flashcards
What are spinal nerves? How are spinal nerves connected to the spinal cord? What is located in each of these “connections”?
Spinal nerves originate in the spinal cord and are mixed nerves of sensory and motor neuron fibers that separate to spinal cord. They are connected to the spinal cord via dorsal and ventral roots.
Dorsal Root: afferent sensory axons of somatic and visceral sensory neurons extend here.
Ventral Root: somatic motor axons that extend from motor neuron cell bodies in ventral horn of grey matter in spinal cord.
How many cervical spinal nerves are there and where are they located?
There are 8 cervical spinal nerves. They are located cranial to each cervical vertebra (CSN 1 is cranial to C1). CSN 8 however is caudal to C7 and cranial to T1.
Cervical spinal nerves emerge through intervertebral foramina and branch into dorsal and ventral branches. What do each of these branches of nerves supply?
The dorsal branch of the cervical spinal nerves supplies the epaxial musculature. The ventral branch supplies the hypaxial musculature.
Where do thoracic and lumbar spinal nerves emerge in relation to their same numbered vertebra?
Caudal to their corresponding vertebra.
Where does the first pair of cervical spinal nerves emerge from?
The lateral vertebral foramina of the atlas.
Where do the 3 sacral spinal nerves emerge from?
The first 2 sacral spinal nerves emerge through the sacral foramina. The third sacral spinal nerve emerges between the intervertebral foramen between the sacrum and the first caudal vertebra.
Describe the ventral branches of cervical spinal nerve 2. Where does it emerge? What are the names of its ventral branches?
It emerges between the cleidomastoideus and the omotransversarius. It has 2 ventral branches: The Great Auricular Nerve and The Transverse Cervical Nerve.
What do the ventral branches of all cervical spinal nerves (except CSN 2) penetrate?
The omotransversarius.
What is another name for Cranial Nerve XI? Where does it pass? What muscle does it supply?
CN XI is also called the Accessory Nerve. Its dorsal branch crosses CSN1 to supply the trapezius muscle. It passes between the brachiocephalicus and the trapezius; dorsal to the omotransversarius.
What is the CNS composed of? What does the CNS do?
CNS relays and integrates information received from the periphery of the body. It is composed of the brain (Grey Matter: Nuclei, White Matter: Tracts) and spinal cord.
What is the PNS composed of? What does the PNS do?
PNS transmits sensory input to the CNS and relays motor output from the CNS to the periphery of the body. Composed of nerves and ganglia.
What are nuclei in the CNS? What do they make up?
Nuclei are collections of neuron cell bodies within the CNS. They make up the grey matter of the CNS
Pre-synaptic Autonomic (Sympathetic and Parasympathetic) cell bodies are located in nuclear regions of….?
PSNS = Brain SNS = Spinal Cord (Thoracolumbar) PSNS = Spinal Cord (Sacral)
What are tracts in regards to the CNS? What do they make up?
Tracts are formed by axonal processes of neurons that travel collectively together to common destination within the CNS. They make up the majority of white matter.
What are afferent sensory neurons? When are afferent sensory neurons bipolar and when are they unipolar?
Relay sensory input to the CNS.
Bipolar Neurons = special sensory systems (olfaction, vision, taste)
Unipolar Neurons = general sensory info from periphery to CNS
What are somatic afferent neurons vs. visceral afferent neurons?
Somatic Afferent Neurons = From skeletal muscle (voluntary) and proprioceptors.
Visceral Afferent Neurons = From involuntary tissue (cardia, smooth muscle, glands)
What are efferent motor neurons? What type of neurons are they? Where are their cell bodies located (be specific in regards to somatic, visceral (PSNS, SNS)?
Relay motor output from the CNS.
Multipolar neurons.
Cell bodies are located within the CNS in nuclei (grey matter):
Somatic: Cell bodies are in the ventral horn of spinal cord grey matter.
SNS pre-synaptic cell bodies: Lateral horn of spinal cord (thoracic and lumbar regions)
PSNS pre-synaptic cell bodies: Ventral horn/dorsal aspect of spinal cord (sacral region)
What are somatic efferent neurons vs. visceral efferent neurons? State whether or not each of these synapse before reaching their target tissue.
Somatic Efferent Neurons = to skeletal (voluntary) muscle. Do not synapse before reaching target tissue.
Visceral Efferent Neurons = to involuntary tissues (comprises ANS). Synapse onto a second neuron (pre-synaptic and post-synaptic)
What are interneurons? Where are they located? What do their axons travel via?
Interneurons integrate information between the CNS and PNS. They are located within the CNS (cell bodies are in nuclei in grey matter). Their axons travel via tracts.
What are ganglia in the PNS? What are nerves?
Ganglia are collections of neuronal cell bodies in the PNS.
Nerves are neuron processes of several neurons travelling together in the PNS
How many pairs of cranial nerves are there? Which 4 contain autonomic neurons & give their common names?
12 pairs. Pairs containing autonomic neurons: CN III: Oculomotor CN VII: Facial CN IX: Glossopharyngeal CN X: Vagus
Discuss the physiological and pharmacological differences between SNS vs. PSNS
SNS: Fight or Flight
Increase energy consumption to prepare for an action, adjust to stress
Adrenergic - release adrenaline
PSNS: Rest and Digest
Enhances activities that gain and conserve energy.
Cholinergic - release acetylcholine
Discuss the anatomical differences between SNS and PSNS.
SNS:
Thoracolumbar Division (Presynaptic Fibers exit T1-L5)
Presynaptic Fibers are SHORT and synapse with sympathetic chain of ganglia (paravertebral) located on either side of spinal cord.
PSNS:
Craniosacral Division (CN III, VII, IX, X) & S2-4
Pre-synaptic Fibers are LONG and synpase in ganglia located within organs they innervate.
Discuss the differences between the SNS and PSNS in regards to the synapse of pre-synaptic neurons onto post-synaptic neurons.
SNS:
Synapse of pre onto post neurons occurs at:
Paravertebral ganglia
Prevertebral ganglia (caudal to diaphragm: celiac, cranial and caudal mesenteric)
Cervicothoracic, middle cervical, cranial cervical ganglia Adrenal Medulla (not ganglion but pre-synaptic fibers can stimulate chromaffin cells resulting in hormonal release of adrenaline)
PSNS:
Synapse of pre onto post synaptic neurons at:
Cranial ganglia (visible in head)
Terminal ganglia (located within muscular walls of viscera (not visible)
Discuss the SNS innervation of sweat glands, cutaneous vessels and erector pili muscles.
Pre-ganglionic neuron cell body is in lateral horn of thoracolumbar spinal cord. Axon (pre-ganglionic fiber) passes back through a ramis communicans to a paravertebral ganglion.
Post-ganglionic neuron cell body is in a chain ganglion (paravertebral). Axon (post-ganglionic fiber) passes back through a ramus communicans to join a spinal nerve and is distributed to skin via cutaneous branch of a dorsal/ventral ramus branch of a spinal nerve.
Discuss the SNS innervation of cranial visceral structures.
Pre-ganglionic = lateral horn of upper thoracic spinal cord. Axon ascends via vagosympathetic trunk to cranial cervical region.
Post-ganglionic = cranial cervical ganglion.
Axon follows blood vessels to visceral structures of the head.
Discuss the SNS innervation of the thoracic viscera.
Pre-ganglionic = lateral horn of thoracic spinal cord.
Axon joins sympathetic chain/trunk via ramus communicans.
Post-ganglionic = cervicothoracic ganglion or middle cervical ganglion. Axon leaves in a cardiac nerve.
Discuss the SNS innervation of the abdominal viscera.
Pre-ganglionic = lateral horn of the lower thoracic or upper lumbar spinal cord. Axon joins the sympathetic chain via a ramus communicans and leaves in a sphanchnic nerve without synapsing onto a paravertebral ganglion. Post-ganglionic = pre-vertebral ganglion. Axon follows a blood vessel to an organ.
Discuss the SNS innervation of the adrenal medulla
Pre-ganglionic = lateral horn of the lower thoracic spinal cord. Axon joins the sympathetic chain via ramus communicans and leaves it in a thoracic (major or minor) splanchnic nerve, which passes over the lumbocostal arch of the diaphragm parallel to the sympathetic trunk to reach the adrenal gland.
Discuss the SNS innervation of the pelvic viscera.
Pre-ganglionic = lumbar spinal cord. Axon joins the lumbar sympathetic trunk via a communicating ramus from a lumbar spinal nerves and leaves the sympathetic trunk via a lumbar splanchnic nerve. Post-ganglionic = caudal mesenteric ganglion. Axon either follows a branch of the caudal mesenteric artery or runs in a R or L hypogastric nerve to the pelvic plexus and then to a pelvic viscus.
Discuss in general the PSNS innervation for cervical, thoracic and abdominal viscera.
Pre-ganglionic = Medulla. Axon leaves the brain in CN X (Vagus Nerve). Post-ganglionic = Terminal ganglion
Which Cranial Nerve is the Vagus Nerve? Which types of fibers does it contain?
CN X (Vagus Nerve) Contains both somatic and autonomic fibers.
When do somatic fibers leave the vagus nerve? When do parasympathetic fibers leave the vagus nerve?
They leave the vagus nerve just past the thoracic inlet (at the level of the middle cervical ganglion). The R and L vagus nerves leave the vagosympathetic trunk and release the R and L recurrent laryngeal nerves (containing the somatic fibers).
Parasympathetic fibers don’t leave! They continue on as the dorsal and ventral vagus nerve trunks to supply the abdominal viscera
Discuss the path travelled by the L recurrent laryngeal nerve and the R recurrent laryngeal nerve.
L recurrent laryngeal nerve leaves the L vagus nerve at the level of the middle cervical ganglion. It wraps around the ligamentum arteriosium and aortic arch and then continues back cranially.
R recurrent laryngeal nerve leaves the R vagus nerve at the level of the middle cervical ganglion and wraps around the R subclavian artery and then continues back cranially.
Describe the path of the vagus nerve.
R and L vagus nerves continue past the base of the heart and then each divides into dorsal and ventral branches. Ventral branches unite cranial to diaphragm to form the ventral vagal trunk (ventral to esophagus, caudal to heart). Dorsal branches unite cranial to diaphragm to form dorsal vagal trunk. Both dorsal and ventral vagal trunks travel with esophagus through the esophageal hiatus to abdominal cavity.
Also gives off celiac branch to celiacomesenteric plexus.
Discuss the PSNS innervation of pelvic viscera.
Pre-ganglionic = lateral region of sacral spinal cord. Axon courses in the ventral root of a sacral spinal nerve and joins the pelvic nerve. Post-ganglionic = terminal ganglion of pelvic viscera.
List the skeletal boundaries of the thorax.
Dorsal: Thoracic Vertebrae Lateral: Ribs and Costal Arches Ventral: Sternebrae and Costal Cartilages Cranial: Thoracic Inlet Caudal: Diaphragm
Discuss the muscular and tendinous parts of the diaphragm.
Muscular Parts: R and L costal parts, Sternal part, Lumbar part with L and R crura.
Tendinous Parts: Central tendon, L and R crural tendons (attach muscular crura to lumbar vertebral bodies)
What is the diaphragmatic line of pleural reflection?
Junction between the costal pleura and the diaphragmatic pleura. Cranial to this line is the costodiaphragmatic recess. Caudal to this line the diaphragm is directly attached to the thoracic wall.
What is the plica venae cavae?
Pleural covering from diaphragm. Envelopes caudal vena cava and right phrenic nerve.
What are the 4 openings through the diaphragm? What goes through each?
Lumbocostal Arch - area between the crura and the vertebrae (not a true opening), potential for herniation. Passage of splanchnic nerve.
Aortic Hiatus - passage of aorta, azygous vein, thoracic duct
Esophageal Hiatus - passage of esophagus, dorsal/ventral vagal trunks
Caval Foramen - passage of caudal vena cava
What is the costodiaphragmatic recess? Where is it located?
Junction where costal pleura reflects onto the surface of the diaphragm. Located between the basal border of the lung and the diaphragmatic line of reflection.
What is the lumbodiaphragmatic recess? Where is it located?
Region where the pleura extends ventrally from the caudal and dorsal thoracic wall to the crura of the diaphragm. Susceptible to herniation.
Which arteries supply the diaphragm? Which nerves supply the diaphragm?
Blood Supply: Musculophrenic artery (branch of internal thoracic artery) & Caudal phrenic artery.
Innervation: R and L phrenic nerves (originate from ventral branches of spinal nerves C5-C7; somatic)
What are serous membranes (aka tunica serosa)? What are they composed of?
Protective layers that secrete serous fluid to reduce friction of organs.
Composed of secretory epithelial layer (mesothelium) and a CT layer that provides blood vessels and nerves.
What are the 3 serous cavities within the thoracic cavity?
- Left pleural cavity
- Right pleural cavity
- Pericardial cavity
What is parietal pleura? What is visceral pleura?
Parietal pleura is pleura that lines the walls of the thoracic cavity and the mediastinum.
Visceral (pulmonary) pleura is pleura that is adhered to the surface of the lung.
What is the mediastinum?
Space between the 2 pleural sacs - where they meet medially. It is continuous with the cervical visceral space.
What are the 4 recesses of the pleura in the thoracic cavity? Describe where they are.
Pleural Cupula: located at the thoracic inlet where pleura reflects from the costal wall to the cranial mediastinum (dog L pleural cupula extends further cranially than R)
Costomediastinal Recess: at junction where the costal pleura reflects from the ventral thoracic wall and extends dorsally bilaterally
Costodiaphragmatic Recess: at junction where the costal pleura reflects onto the surface of the diaphragm, bilateral.
Mediastinal Recess: located between the R mediastinal pleura and the plica venae cavae (accessory lobe of R lung is in this recess)
What are the 3 components of the pericardium (pericardial cavity/sac)? Where does it develop?
Develops within the mediastinum.
3 components:
1. Parietal Pericardium: innermost layer of pericardial sac
2. Fibrous Pericardium: middle layer of pericardial sac (continues as the phrenicopericardial ligament in dog/cat or the sternopericardial ligament in LA)
3. Pericardial Mediastinal Pleura: outermost layer - formed by mediastinal pleura.
What is located within the mediastinum?
Trachea
Esophagus
Aorta (ascending, aortic arch, descending thoracic)
Lymphatic Structures (thoracic duct, sternal/mediastinal/tracheobronchial lymph nodes)
Thymus
Right azygous vein (R only in dog/horse, R and L in ox)
Paravertebral/sympathetic chain of ganglia (R and L)
R and L vagus nerves (dorsal/ventral branches/trunks)
Right recurrent laryngeal nerve
Left recurrent laryngeal nerve
R and L phrenic nerve
Pericardium and Heart
What are the components of the conducting portion of the respiratory system and the exhange portion?
Conducting Portion: Trachea (incomplete cartilaginous rings connected by tracheal annular ligaments, trachealis m. completes ring dorsally) Bronchial Tree: Principal bronchi (originate where trachea bifurcates - CARINA = partition between L and R principal bronchi at their origin from trachea), Lobar bronchi (branch from principal bronchi and supply lobes of lungs), Segmental bronchi (branch from lobar bronchi and supply bronchopulmonary segments), Bronchioles (branches of segmental bronchi that terminate as respiratory bronchioles) Exchange Portion: Respiratory Bronchioles Alveolar Ducts Alveolar Sacs Alveolus
Describe the differences in the lobes of the lungs between carnivores, ruminants and the horse.
Carnivores:
L lung: Divided cranial lobe, caudal lobe
R lung: Cranial lobe, middle lobe, caudal lobe, accessory lobe
Ruminants:
L lung: Divided cranial lobe, caudal lobe
R lung: Divided cranial lobe, middle lobe, caudal lobe, accessory lobe
Horse:
L lung: Cranial lobe, caudal lobe
R lung: Canial lobe, caudal lobe, accessory lobe
Horse has NO middle lobe
Where do you listen to the Left Lung and Right Lung in Canine, Ruminant and Horse?
Left Lung:
Canine: Between cranial and caudal parts of cranial lobe. Between 3 and 4 intercostal spaces.
Ruminant: Between 3 and 4 intercostal spaces.
Horse: Between 3 and 6 intercostal spaces
Right Lung:
Canine: Between ventral aspect of the cranial lobe and middle lobe. Within the 4 intercostal space, extends to 5
Ruminant: Spans 3 and 4 intercostal space.
Horse: Spans 3 and 4 intercostal space.
What is the hilus of the lung?
Region of lung that is perforated by vessels, nerves and bronchi
What is the functional blood supply of the lungs? What is the nutritional blood supply of the lungs?
Functional: Pulmonary arteries/veins
Nutritional: Bronchoesophageal artery, azygous vein
All species have deep fissures separating the lobes (external lobations) EXCEPT…?
The horse.
List the branches off of the L and R subclavian arteries and describe what they supply.
- Vertebral Artery - extends through transverse vertebral foramina to supply the brain
- Costocervical Trunk - supplies cranial intercostal spaces and muscles of the neck.
- Superficial Cervical Artery - supplies superficial structures of the neck
- Internal Thoracic Artery - Ventral intercostal arteries (intercostal spaces), musculophrenic artery (diaphragm), then continues as cranial epigastric artery
Describe the ductus arteriosus and the ligamentum arteriosum.
Ductus arteriosus - fetal structure that serves to shunt blood from the pulmonary trunk to the aorta bypassing pulmonary circulation to nonfunctional lungs.
Ligamentum arteriosum - fibrous remnant of ductus arteriosus in adult.
What happens if there is a vascular ring anomaly in the ligamentum arteriosum?
May constrict the esophagus. PRAA - Persistent Right Aortic Arch: R aortic arch forms, L regresses, esophagus gets trapped leading to megaesophagus.
What is epicardium, myocardium and endocardium?
Epicardium: Visceral pericardium
Myocardium: Muscle of the heart
Endocardium: Endothelial lining of the heart chamber
Describe the orientation of the heart within the thoracic cavity?
Positioned obliquely.
Base = craniodorsal
Apex = caudoventral
Lies at 45 degree angle in dog
What are the 4 main surfaces of the heart and where are they located?
Sternal Surface - cranioventral (RV, conus arteriosus)
Diaphragmatic Surface - caudodorsal (LV0)
Auricular Surface - both auricles in view, L side of animal
Atrial Surface - both atria in view
Where is the paraconal interventricular groove located on the heart? What is within it?
It is adjacent to the conus arteriosus of the RV. On the auricular surface of what would be the border between the 2 ventricles.
Great cardiac vein and the Left Coronary Artery are within the groove.
Where is the coronary groove of the heart located? What is within it?
Encircles the base of the heart. Located between atria and ventricles.
Coronary vessels are within the groove.
Where is the subsinuosal interventricular groove located? What is within it?
On caudodorsal surface.
Circumflex branch of left coronary artery is within groove (dog/ox)
Describe the nutritional blood supply to the heart itself.
R coronary artery: encircles R side of heart in coronary groove and extends to the caudodorsal surface. Continues to the subsinuosal interventricular groove as the subsinuosal interventricular branch (in horse/pig)
L coronary artery: branches into the paraconal interventricular branch and circumflex branch. In dog/ox, gives off the subsinuosal interventricular branch.
Great cardiac vein: begins in paraconal interventricular sulcus and returns blood supplied to heart by the left coronary artery. Expands as coronary sinus where it empties into right atrium.
Describe the anatomy of the auricle of the RA?
Crista Terminalis - boundary between auricle and sinus
Contains pectinate muscles
List the openings into/out of the RA and describe them.
Cranial vena cava - delivers blood from upper body
Caudal vena cava - delivers blood from lower body
Coronary sinus - delivers blood from heart muscle
Foramen ovale - between L and R atria that allows blood to bypass pulmonary cirulation (Closed after birth = Fossa Ovalis)
Right Atrioventricular Orifice - closed by AV valve during ventricular systole. (Parietal Cusp: originates from outer/marginal ventricular wall, Septal Cusp: originates from the interventricular septal wall)
Azygous vein - may empty directly into RA or into cranial vena cava
List the openings into/out of the LA and describe them.
Numerous pulmonary veins open into LA.
Left Atrioventricular Orifice - closed by AV valve during ventricular systole (Parietal Cusp, Septal Cusp)
List the important anatomical features of the RV and describe them.
Papillary muscles (Chordae tendineae - extend from cusps of AV valve to the papillary muscles) Trabeculae septomarginalis - from interventricular septal wall to the parietal wall of ventricle (part of conducting system) Conus arteriosus - cone shaped portion of RC that extends craniodorsally toward the pulmonary trunk Pulmonary Semilunar Valve - guards opening between RV and pulmonary trunk (Cusps: L, intermediate, R; Pulmonary Sinuses: within cup formed by each cusp)
List the important anatomical features of the LV and describe them.
Papillary muscles (Chordae tendineae) Trabeculae Septomarginalis Aortic Semilunar Valve (guards opening between teh LV and the aorta; cusps & nodules; Aortic sinuses: L aortic sinus (origin of L coronary artery), R aortic sinus (origin of R coronary artery) Interatrial Septum Interventricular Septum
For maximum intensity where would you listen for the Pulmonary Valve, Aortic Valve, L AV Valve and R AV Valve in the dog?
Left Side:
Pulmonary Valve: 3 IC space
Aortic Valve: 4 IC space
L AV Valve: 5 IC space
Right Side:
R AV Valve: 4 IC space
For maximum intensity where would you listen for the Pulmonary Valve, Aortic Valve, L AV Valve and R AV Valve in the horse?
Left Side:
Pulmonary Valve: 3 IC space below shoulder
Aortic Valve: 4 IC space
L AV Valve: 5 IC space
Right Side:
R AV Valve: 3/4 IC space
For maximum intensity where would you listen for the Pulmonary Valve, Aortic Valve, L AV Valve and R AV Valve in the ox?
Left Side:
Pulmonary Valve: 3 IC space below shoulder
Aortic Valve: upper 4 IC space
L AV Valve: lower 4 IC space
Right Side:
R AV Valve: 3/4 IC space
What happens in patent ductus arteriosus?
Blood is shunted from left to right (foramen ovale/fossa ovalis)
Causes congestive heart failure
Treatment: thoracotomy/occlusion catheter
What is pericardial effusion?
Accumulation of fluid in the pericardial sac. Many causes.
What is dilated cardiomyopathy?
Abnormality in myocardium that leads to decreases contractility.
Common in Dobermans.
Increase in L ventricular volume and diameter which leads to congestive heart failure.
What is hypertrophic cardiomyopathy?
Disease causing LV thickening. Most common cardiac disease for cats.
What is mitral valve deficiency?
Degenerative, progresses over time.
Common in King Charles Cavalier Spaniels.
Congenital.
What are the 9 regions of the abdomen?
Cranial Abdominal Region: Middle = Xiphoid, L and R Hypochondriac
Middle Abdominal Region: Middle = Umbilical, L and R Lateral Abdominal
Caudal Abdominal Region: Middle = Pubic, L and R inguinal
What are the Specific Names for Lumbar Spinal Nerves 1-4?
L1: Cranial Iliohypogastric
L2: Caudal Iliohypogastric
L3: Ilioinguinal
L4: Lateral Cutaneous Femoral
Which nerves innervate the abdominal wall?
Ventral Branches of Spinal Nerves T13-L5
Lateral cutaneous branches - located between skin and external abdominal oblique muscles
Medial branches - located between internal abdominal oblique and transversus abdominus msucles.
What is the blood supply for the 4 mains quadrants of the abdominal wall (Craniodorsal, Caudodorsal, Cranioventral, Caudoventral)?
Craniodorsal: Phrenicoabdominal Artery
Caudodorsal: Deep Circumflex Iliac Artery
Cranioventral: Cranial Epigastric Artery, Cranial Superficial Epigastric Artery
Caudoventral: Caudal Epigastric Artery, Caudal Superficial Epigastric Artery
What is the blood supply for the mammae?
Provided by cranial and caudal superficial epigastric arteries.
Internal Thoracic Artery –> cranial epigastric –> cranial superficial epigastric
External Pudendal –> Caudal superficial epigastric
What is located within the superficial inguinal ring?
vaginal process/tunic, genitofemoral nerve, external pudendal artery and vein, cremaster muscle
What is the rectus sheath?
The aponeuroses of the abdominal oblique muscles (internal and external) and the transversus absominis that form a sheath around the rectus abdominis
What is the inguinal canal?
A flattened canal between the deep and superficial inguinal rings
What is the superficial inguinal ring?
Opening in aponeurosis of external abdominal oblique. Located between the pelvis and abdominal tendons.
What is the deep inguinal ring?
Anatomical area defined by boundaries:
Cranial: Caudal border of internal abdominal oblique muscle
Medial: Rectus abdominis
Lateral and Caudal: Inguinal ligament.
What are the boundaries of the abdominal cavity?
Cranial: Diaphragm
Caudal: Pelvic Inlet
Dorsal: Lumbar Vertebrae and transverse processes, crura of diaphragm, sublumbar muscles
Lateral: Intrathoracic - ribs and costal arch, intercostal muscles. Extrathoracic - muscles of abdominal wall.
What are mesenteries? What are dorsal mesenteries vs. ventral mesenteries?
Double layer of peritoneum that connect the viscera to the dorsal and ventral body walls.
Dorsal mesenteries are extensions from the dorsal body wall.
Ventral mesenteries are extensions from the ventral body wall.
List the dorsal mesenteries of the abdominal cavity.
Greater omentum (gastrosplenic ligament; has superficial and deep leaves that enclose the omental bursa)
Mesoduodenum (Duodenocolic fold)
Mesojejunum
Mesoileum
Mesocolon
Mesorectum
Lateral ligaments of urinary bladder: contain remnants of the umbilical arteries = round ligaments
List the ventral mesenteries of the abdominal cavity.
Falciform ligament: contains remnants of umbilical vein = round ligament of liver
Lesser omentum
Median ligament of bladder: supports urachus of fetus