Anatomy Flashcards
What are the 4 vertical lines of the chest wall called?
- Mid-clavicular.
- Anterior axillary line.
- Mid axillary line.
- Posterior axillary line.
What is the origin and insertion of a muscle?
The origin is the fixed attachment of the muscle, where the muscle starts. The insertion will move with contraction and is where the muscle ends.
What is the innervation of pectoralis major?
Medial and lateral pectoral nerves.
What is the action of pectoralis major?
Adduction and medial rotation of the humerus at the shoulder.
What is the innervation of pectoralis minor?
Medial pectoral nerve.
What is the action of pectoralis minor?
Protraction of the shoulder.
What is the innervation of serratus anterior?
Long thoracic nerve.
What is the action of serratus anterior?
Protraction of the scapula.
What is the function of the lungs?
Oxygenates blood by bringing inspired air into contact with O2 poor blood in the pulmonary capillaries.
What is the innervation of the intercostal muscles?
The intercostal nerves.
What does the internal thoracic artery branch into?
- Musculophrenic - supplies the diaphragm.
2. Superior epigastric arteries - supplies the front of the abdomen.
What is the pleural cavity?
A potential space between the visceral and parietal pleura.
Name 2 functions of the serous fluid within the pleural cavity?
- Lubricates the pleurae.
2. Creates a surface tension helping the lungs to expand on inspiration.
Name the 4 main structures that are found at the hilum of the lung.
- Pulmonary artery x1.
- Bronchus x1.
- Pulmonary vein x2.
What branch does the right main bronchus give off outside of the right lung?
Superior lobar bronchus.
What other smaller vessels are found at the hilum of the lung?
- Bronchial arteries.
- Pulmonary plexus of autonomic nerves.
- Lymph nodes.
Which lung are inhaled foreign bodies most likely to be found in and why?
The right lung. The right main bronchus is shorter and more vertical.
How many lobes does the right lung have and what are they called?
3 lobes.
Superior, middle and inferior.
How many lobes does the left lung have and what are they called?
2 lobes.
Superior and Inferior.
What is the fissure in the left lung called?
Oblique (lies along 6th rib).
What are the fissures in the right lung called?
Horizontal (extends from mid-axiallry line anteriorly along the 4th rib) and Oblique (lies along 6th rib).
Name the 3 surfaces of the lungs.
- Costal.
- Mediastinal.
- Diaphragmatic.
Name the 3 borders of the lungs.
- Anterior.
- Posterior.
- Inferior.
Describe the innervation of the lungs?
- Parasympathetic innervation derived from vagus nerve.
- Sympathetic innervation derived from sympathetic trunks.
- Visceral afferent - conducts pain impulses to sensory ganglion.
What is the action of parasympathetic innervation in the lung?
Bronchoconstriction and vasodilation of pulmonary vessels.
What is the action of sympathetic innervation in the lung?
Bronchodilation and vasoconstriction of vessels that are poorly ventilated.
What are the 3 branches of the arch of the aorta?
- Brachiocephalic trunk.
- Left common carotid artery.
- Left subclavian artery.
What are the branches of the brachiocephalic trunk?
Right common carotid (LHS). Right subclavian (RHS).
What is the ligamentum arteriosum a remnant of and what was its function in the foetus?
Remnant of the ductus arteriosum.
It’s function was to shunt blood between the pulmonary trunk and the aorta in order to bypass the non-functioning lungs.
What branch does the left vagus nerve give off as it crosses the arch of the aorta?
The left recurrent laryngeal nerve.
What spinal roots is the phrenic nerve derived?
C3, 4 and 5 (cervical plexus).
What does the phrenic nerve supply?
Motor innervation to the diaphragm.
Sensory innervation to the pleura, peritoneum and pericardium.
Does the phrenic nerve enter the diaphragm? If so where?
Yes. It pierces the central tendon of the diaphragm alongside the IVC on the right (T8).
Does the vagus nerve enter the diaphragm? If so where?
Yes. Through the oesophageal hiatus (T10).
What are the layers of the pericardium?
- Outer fibrous layer.
- Parietal serous layer.
- Visceral serous layer.
What structures form the left border of the heart?
- Left pulmonary artery.
- Left auricular appendage.
- Left ventricle.
What is the surface marking for the apex of the heart?
5th intercostal space in the mid-clavicular line.
What forms the right border of the heart?
The right sternal edge.
On what aspect of the heart would you find the left atrium?
The posterior aspect. It is closely related to the oesophagus.
Where is the RCA found?
In the atrio-ventricular sulcus.
Name the 3 main branches of the RCA.
- Sino-atrial nodal branch.
- Right marginal branch.
- Posterior inter-ventricular branch.
In 90% of hearts where does the posterior inter-ventricular artery arise from?
RCA.
In 30% of hearts where does the posterior inter-ventricular artery arise from?
The circumflex artery.
Name the 2 main branches of the LCA.
- Circumflex.
2. Left anterior descending (LAD).
In what sulcus does the circumflex artery lie? What other large vessel can be found here?
Left atrio-ventricular sulcus.
The coronary sinus can also be found here. IT passes posteriorly and drains into the RA.
Where is the SAN located?
The upper aspect of the crista terminalis in the RA.
Where is the AVN located?
Inter-atrial septum.
Name the artery that supplies:
a) The SAN
b) The AVN
a) Sino-atrial nodal branch of RCA.
b) Posterior inter-ventricular branch, usually RCA.
At what phase of the cardiac cycle do the coronary arteries fill?
Diastole; when the ventricles are relaxed.
What 2 spaces does the crista terminalis divide in the RA?
It divides the smooth walled atrium from the trabeculated auricle - ridges = musculi pecanti.
What is the Fossa Ovalis a remnant of?
The Foramen Ovale. In the foetus the foramen ovale shunted blood from the RA to the LA so as to bypass the lungs.
In the ventricles, what are the chordae tendinae attached to?
The valves (mitral or tricuspid) and the papillary muscles.
How do the mitral and tricuspid valves work?
They open passively when the atria contract and then close afterwards to prevent backflow. The papillary muscles and chordae tendinae work to keep the valves closed during ventricular contraction.
How do the atrial and pulmonary valves work?
They open passively when the ventricles contract. Towards the end of systole they close to prevent the back flow of blood. The pressure of blood on the valves keeps them closed.
How would you know if the atrial and pulmonary valves were incompetent?
You would get regurgitation of blood into the ventricles. This could be heard as a diastolic murmur.
Where can you hear the pulmonary valve?
Left of the sternum, 2nd intercostal space.
Where can you hear the aortic valve?
Right of the sternum, 2nd intercostal space.
What is the midline connection called of the two lateral thyroid gland lobes?
Isthmus.
What tracheal rings does the isthmus of the thyroid gland lie in front of?
2nd, 3rd and 4th.
Where do the thyroid arteries arise from?
- Superior thyroid artery - External carotid artery.
2. Inferior thyroid artery - Thyrocervical trunk, a branch of the Subclavian artery.
What vessels are contained within the carotid sheath?
- Carotid artery.
- Jugular vein.
- Vagus nerve.
What nerve(s) are related to the superior thyroid arteries?
The external laryngeal nerves.
What nerve(s) are related to the inferior thyroid arteries?
The recurrent laryngeal nerve crosses the inferior thyroid artery.
How many parathyroid glands are there?
4.
Where are the parathyroid glands located?
Posterior surface of thyroid glands.
How are the parathyroid glands developed?
From the pharyngeal pouches.
Name 3 functions of the larynx.
- Phonation.
- Cough reflex.
- Protection of the lower respiratory tract.
What is the epithelium of the vocal folds? and why?
Stratified squamous epithelium. This is more robust and can withstand the vibrations and wear and tear.
What is the blood supply to the larynx?
Superior and inferior laryngeal arteries (branches of the thyroid arteries).
What does the recurrent laryngeal nerve supply?
Motor innervation to intrinsic muscles of the larynx (except cricothyroid).
What does the internal branch of the superior laryngeal nerve supply?
Sensory innervation to laryngopharynx and larynx.
What does the external branch of the superior laryngeal nerve supply?
Motor innervation to the cricothyroid muscle.
Name the 3 unpaired cartilages in the larynx.
- Epiglottis (elastic cartilage).
- Thyroid (hyaline cartilage).
- Cricoid (hyaline cartilage).
What do the two sheets of thyroid cartilage form in the midline?
The laryngeal prominence (Adam’s apple).
What do the inferior horns of the thyroid cartilage articulate with?
They form a synovial joint with the cricoid cartilage.
What do the superior horns of the thyroid cartilage articulate with?
The hyoid bone.
What vertebral level is the inferior border of the larynx at?
C6.
Name the 3 paired cartilages in the larynx.
- Arytenoid.
- Cuneiform.
- Corniculate.
What do the arytenoid cartilages articulate with?
The base articulates with the cricoid cartilage and the apex articulates with the corniculate cartilages.
Where are cuneiform cartilages located?
Within the ary-epiglottic folds. They strengthen the folds.
What is the space between the vocal cords called?
Rima glottidis.
What is the superior vestibular folds also known as?
False vocal folds.
What are the extrinsic muscles of the pharynx?
The suprahyoids, infrahyoids and stylopharyngeus.
What is the function of the extrinsic muscles of the larynx?
They move the larynx superiorly and inferiorly during swallowing.
Name the 4 infrahyoid muscles.
- Omohyoid (scapula to hyoid).
- Sternohyoid (sternum to hyoid).
- Sternothyroid (sternum to thyroid).
- Thyrohyoid (thyroid to hyoid).
What is the function of the intrinsic muscles of the larynx?
They control the shape of the rima glottidis, and the length and tension of the vocal folds.
What is the innervation of the intrinsic laryngeal muscles?
Recurrent laryngeal nerve.
What intrinsic laryngeal muscle is not innervated by the recurrent laryngeal nerve?
Cricothyroid.
What is the innervation of the cricothyroid muscle?
External branch of the superior laryngeal nerve.
What is the function of the cricothyroid muscles?
Stretches and tenses the vocal cords. Important for the creation of speech.
What is the function of the thyroarytenoid muscles?
Relaxes the vocal ligament, allowing for a softer voice.
What is the function of the posterior cricoarytenoid muscles?
Abduction of the vocal cords; the only muscles capable of widening the rima glottidis.
What is the function of the lateral cricoarytenoid muscles?
Adduction of the vocal folds; narrow the rima glottidis.
What is the function of the transverse arytenoids muscles?
Adduction of the arytenoid cartilages, narrows the laryngeal inlet.
What nerve passes through the parotid gland?
The facial nerve - Cn 7.
What are the 5 branches of Cn 7.
- Temporal.
- Zygomatic.
- Buccal.
- Mandibular.
- Cervical.
Where does the pharynx extend from and to?
The base of the skull to the cricoid cartilage (C6).
What are the 3 sections of the pharynx called?
- Nasopharynx.
- Oropharynx.
- Laryngopharynx.
What is the function of the pharyngeal constrictor muscles?
They contract sequentially to propel food into the oesophagus.
What is the origin of the superior constrictor?
Pterigoid plate and pterygomandibular raphe.
What is the origin of the middle constrictor?
Hyoid bone.
What is the origin of the inferior constrictor?
Thyroid and cricoid cartilages.
What is the innervation of the pharyngeal constrictors?
The pharyngeal branch of the Vagus nerve.
What is the function of the longitudinal pharyngeal muscles?
They shorten and widen the pharynx. They also elevate the pharynx during swallowing.
What are the 3 longitudinal pharyngeal muscles called?
- Stylopharyngeus.
- Salpingopharyngeus.
- Palatopharyngeus.
What is the origin of the stylopharyngeus and what is its innervation?
Origin: Styloid process of temporal bone.
Innervation: Glossopharyngeal, Cn 9.
What is Killian’s dehiscence?
The weakest part of the pharyngeal wall. Located inferiorly in the midline. It is the commonest site for a pharyngeal diverticulum.
What vessels are found in the carotid sheath?
- Common carotid artery.
- Vagus nerve.
- Internal jugular vein.
Where is the carotid sinus located?
At the bifurcation of the common carotid artery.
Where does the glossopharyngeal nerve exit the cranial cavity?
Through the jugular foramen.
What nerve supplies sensory and taste innervation to the posterior 1/3 of the tongue.
The glossopharyngeal nerve.
What does elevation of the soft palate do?
It closes the orifice between the nasopharynx and oropharynx. This occurse during swallowing to prevent food refluxing into the nose. It also occurs in phonation.
What nerve supplies sensory sensation to the anterior 2/3 of the tongue?
The trigeminal nerve, Cn 5.
What nerve supplies taste sensation to the anterior 2/3 of the tongue?
The facial nerve, Cn 7.
What folds bind the tonsilar fossa?
Palatoglossal (anterior) and Palatopharyngeal (posterior) folds.
What is the function of the tonsils?
The tonsils are a consolidation of lymphoid tissue. They prevent infection by stopping germs entering the mouth and nose.
Give 4 functions of the nasal cavity.
- Warms and humidifies air.
- Olfaction.
- Removes and traps pathogens.
- Drains and clears para-nasal sinuses.
What is the function of the nasal conchae?
They increase the SA of the nose and they disrupt the fast flow of air. This means the air spends more time in the nasal cavity so it can be humidified.
What opens into the inferior meatus?
Nasolacrimal duct.
What opens into the middle meatus?
The frontal, maxillary and anterior ethmoid sinuses open at the hiatus semilunaris. The middle ethmoid sinus opens onto the ethmoidal bulla.
What opens into the superior meatus?
The posterior ethmoid sinus.
Where does the sphenoid sinuses open into the nasal cavity?
At the spheno-ethmoidal recess.
Why does the nose have a rich vascular supply?
This means it can change the humidity and temperature of inspired air.
What nerve supplies general sensation to the nose?
Branches of the trigeminal nerve.
What vertebral level is the tracheal bifurcation?
T4.
What is the function of the thoracic duct?
It drains all the lymph from the lower half of the body and bowel back into the blood stream.
Where does the thoracic duct drain into?
The confluence between the left jugular vein and left subclavian vein.
Where does the azygous vein drain into?
The superior vena cava.
What are the names of the three splanchnic nerves?
The greater (T5-9), the lesser (T10-11) and the least (T12).
What is the function of the splanchnic nerves?
They provide sympathetic innervation to the foregut, midgut and hindgut.
Occlusion of which vessel is most likely to result in a fatal heart attack?
The left main coronary artery.
Which artery provides the main blood supply to the left ventricle?
The left anterior descending artery.
Which vessel is most likely to become occluded without producing any symptoms?
Right marginal artery.
What is stenosis?
Narrowing.
Which artery most frequently supplies the AVN?
The right main coronary artery.
What 2 vertical lines divide the abdomen into it’s 9 nine regions?
Mid-clavicular lines that extend to the mid-inguinal point.
What 2 horizontal lines divide the abdomen into it’s 9 nine regions?
Upper - Subcostal: joins lower costal margins.
Lower - Intertubercular: connects the iliac crests.
How would you draw the transpyloric plane?
Half way between the suprasternal notch and the pubic symphysis.
What vertebral level is the transpyloric plane found?
L1.
Name 5 structures found on the transpyloric plane.
- Pylorus of stomach.
- Fundus of gall bladder.
- Pancreas.
- Hilum of Kidneys.
- Duodenojejunal flexure.
How would you draw the transtubercular plane?
Joins the iliac crests of the pelvis.
What vertebral level is the transtubercular plane found at?
L4. (Same level as the bifurcation of the abdominal aorta).
What is the intercristal plane?
It joins the highest points of the pelvis at the back.
What vertebral level is the intercristal plane found at? Why is this important?
Between the L4 and L5 vertebrae. This is important for lumbar punctures and epidurals.
What is the subcostal plane and at what vertebral level does it lie?
It joins the lower points of the costal margins and lies at the L2 level.
What can the subcostal plane (L2) be a marker for?
- The end of the spinal cord.
- The superior mesenteric artery.
What is McBurney’s point?
2/3 of the way along a line extending from the umbilicus to the right anterior superior iliac spine.
What is the significance of McBurney’s point?
Marks the base of the appendix and can act as a guide for the location of the caecum.
Name the 3 flat muscles of the Abdominal wall.
- External Oblique.
- Internal Oblique.
- Transversus Abdominis.
In what direction do the fibres of the flat muscles run in?
- External oblique - inferiorly and medially (down and in).
- Internal oblique - superiorly and medially (up and in).
- Transversus abdominis - transversely.
What is the origin of external oblique?
Lower 8 ribs and thoraco-lumbar fascia.
What is the insertion of external oblique?
Pubic crest, pubic tubercle, iliac crest and linea alba.
What is the origin of internal oblique?
Thoraco-lumbar fascia, iliac crest, lateral 1/2 of the inguinal ligament.
What is the insertion of internal oblique?
Linea alba, pubic tubercle.
What is the origin of transversus abdominis?
Thoraco-lumbar fascia, iliac crest, lateral 1/3 of the inguinal ligament.
What is the insertion of transversus abdominis?
Linea alba, pubic tubercle.
What are the fibrous intersections of the rectus abdominis called?
Tendinous intersections.
What are the attachments of rectus abdominis?
Rectus sheath, pubis, costal cartilages.
Name 5 structures contained within the rectus sheath.
- Rectus Abdominis.
- Sup and inf epigastric arteries.
- Sup and inf epigastric veins.
- Nerves.
- Lymphatics.
What is the inferior epigastric artery a branch of?
The external iliac artery.
What is the internal thoracic artery a branch of? And what does it supply?
It is a branch of the subclavian artery and it supplies the anterior chest and abdominal wall and also the breasts.
Define dermatome.
An area of skin supplied by nerves from a single spinal root.
What are the dermatomes of the abdominal wall?
T7 to L1.
If a disease process involves the peritoneum of the abdominal wall, then the pain is localised. Why is this?
The peritoneum covering the inside of the abdominal wall has the same sensory nerve supply as the overlying skin.
What is the epithelium lining of the abdominal cavity?
Simple squamous epithelium.
What is the peritoneal cavity?
A potential space between the visceral and parietal peritoneum. It is filled with peritoneal fluid.
What is a retroperitoneal organ?
An organ that only has it’s anterior surface covered by peritoneum. These organs lie behind the peritoneum.
Name 6 retroperitoneal organs.
Duodenum, ascending colon, descending colon, pancreas, oesophagus, kidneys. (DADPOK).
What is an intraperitoneal organ?
An organ fully covered in visceral peritoneum. It is suspended in the peritoneal cavity.
Name 6 intraperitoneal organs.
Sigmoid colon, appendix, liver, transverse colon, stomach, small intestine. (SALTSS).
What connects the lesser sac to the greater sac?
The epiploic foramen.
What does the lesser omentum attach to?
It extends from the liver and attaches to the lesser curvature of the stomach and the first part of the duodenum.
What is found in the right free border of the lesser omentum?
- Common bile duct.
- Hepatic artery.
- Hepatic portal vein.
Where is attached to the greater curvature of the stomach?
The greater omentum.
Describe the position and folding of the greater omentum in the peritoneal cavity.
It hangs down like an apron and then folds back on itself meaning there are 4 layers. The posterior 2 layers go on to enclose the transverse colon (transverse mesocolon) and then form the parietal peritoneum of the posterior abdominal wall.
What is it called when the peritoneal cavity becomes distended by fluid?
Ascites.
With a patient in a supine (lying down) position, where might fluid collect in the abdomen?
In the right retrohepatic space.
What embryological structure forms the ligamentum teres?
The umbilical vein.
Which structures surround the epiploic foramen?
- Anteriorly: lesser omentum.
- Posteriorly: IVC.
- Inferiorly: duodenum.
- Superiorly: caudate lobe of liver.
What connects the jejunum to the posterior abdominal wall?
Small intestine mesentery.
What parts of the large intestine are intraperitoneal?
The transverse and sigmoid colon.
Define lesser sac.
A peritoneal sac that lies posteriorly to the stomach and lesser omentum. It communicates with the greater sac through the epiploic foramen.
What lies in the free border of the lesser omentum?
The hepatic artery, hepatic portal vein and common bile duct.
What structures lie posteriorly to the stomach?
Pancreas, diaphragm, splenic artery and vein.
Name the 4 main regions of the stomach.
- Cardia.
- Fundus.
- Body.
- Pylorus.
What vertebral levels does the stomach lie between?
T7 to L3.
What are the folds of the internal stomach surface called?
Rugae.
Name the 2 sphincters of the stomach.
- Inferior oesophageal sphincter.
2. Pyloric sphincter.
Which sphincter of the stomach is physiological (containing no sphincteric muscle)?
The inferior oesophageal sphincter.
What forces act on the inferior oesophageal sphincter?
- The diaphragm exerts a pressure on the hiatus.
- The lumen is collapsed in the normal state.
- The oesophagus enters the stomach at a right angle; when the stomach is full this is closed off.
What is the function of the pyloric sphincter?
Controls the exit of chyme from the stomach.
What vertebral level is the coeliac trunk found?
T12.
Where does the foregut begin and end?
The mouth to the 2nd part of the duodenum (major duodenal papilla).
What is the blood supply to the greater curvature of the stomach?
The short gastrics, and the right and left gastro-epiploic arteries.
What is the blood supply to the lesser curvature of the stomach?
The left and right gastric arteries.
What is the right gastric artery a branch of?
The proper hepatic artery which arises from the common hepatic artery from the coeliac trunk.
What is the right gastro-epiploic artery a branch of?
It is the terminal branch of the gastroduodenal artery, this arises from the common hepatic artery which arises from the coeliac trunk.
What is the left gastro-epiploic artery a branch of?
The splenic artery which arises from the coeliac trunk.
What vein does venous blood from the GI tract, liver and spleen drain into?
The hepatic portal vein (goes to the liver).
What supplies sympathetic innervation to the stomach (foregut)?
The greater splanchnic nerve (T5-T9).
What supplies parasympathetic innervation to the stomach (foregut)?
The Vagus nerve Cn 10.
Is contraction of the stomach sphincters a sympathetic or parasympathetic action?
Sympathetic. (Parasympathetic = rest and digest).
At what vertebral level does the oesophagus pass through the stomach?
T10.
What structures pass through the diaphragm along side the oesophagus?
Vagus nerves and the oesophageal arteries and veins.
What does the left gastric artery supply?
The superior part of the lesser curvature of the stomach.
What structures lie anterior to the stomach?
The anterior abdominal wall and the left lobe of the liver.
What nerve lies anterior to the abdominal oesophagus and which posterior?
Left vagus - anterior.
Right vagus - posterior.
(LARP)
What are the 3 divisions of the small intestine called?
- Duodenum.
- Jejunum.
- Ileum.
What is the principle function of the small intestine?
Digestion and absorption of food.
What are the folds of mucosa inside the small intestine called?
Plicae circulares.
What are Peyer’s patches?
Large, sub-mucosal, lymph nodules.
Where in the small intestine would you find Peyer’s patches?
Ileum.
Is the duodenum intraperitoneal or retroperitoneal?
Retroperitoneal.
The first part of the duodenum is prone to peptic ulceration. What artery can this affect?
The gastro-duodenal artery. This artery lies in direct contact with the posterior wall of the first part of the duodenum.
Would you describe the jejunum and ileum as intraperitoneal or retroperitoneal?
Intraperitoneal.
What part(s) of the small intestine can become twisted? This results in strangulation and ischaemia.
Jejunum and ileum.
Which has a thicker intestinal wall, the jejunum or the ileum?
Jejunum.
Describe 5 characteristics of the Jejunum.
- Thick intestinal walls.
- Longer vasa recta.
- Less arterial arcades.
- Pronounced plicae circulares.
- Red in colour.
Describe 5 characteristics of the Ileum.
- Thin intestinal walls.
- Shorter vasa recta.
- More arterial arcades.
- Peyer’s patches.
- Pink in colour.
Where might you find Meckel’s diverticulum?
1 meter from the termination of the ileum.
What is Meckel’s diverticulum an embryonic remnant of?
The attachment of the mid-gut to the yolk sac.
Where does the mid-gut begin and end?
3rd part of duodenum to 2/3 along the transverse colon.
What is the blood supply to the midgut?
Superior mesenteric artery (L1).
What is the first branch of the SMA?
Inferior pancreaticoduodenal artery?
Name 3 major branches of the SMA.
- Ileo-colic.
- Right colic.
- Middle colic.
What does the right colic artery supply?
The ascending colon.
What does the middle colic artery supply?
The transverse colon.
Into which vein does blood from the jejunum and ileum drain and what is the final destination of the blood?
Drains into the superior mesenteric vein.
This vein combines with the splenic vein to form the hepatic portal vein which then goes on to the liver.
Which foodstuffs are absorbed through the lymphatic system?
Fats.
What is the innervation of the small intestine?
Sympathetic: Lesser splanchnic (T10-11). Parasympathetic: Vagus. No somatic innervation.
Name 4 mechanisms that ensure a high surface area for absorption of nutrients in the intestine.
- Pliae circularis.
- Coiled length.
- Villi.
- Microvilli.
What is the main function of the large intestine?
Water absorption and the formation of faeces.
State whether the caecum is intraperitoneal or retroperitoneal and describe the blood supply and venous drainage.
- Intraperitoneal.
- Ileocolic artery.
- Ileocolic vein; drains into superior mesenteric vein.
State whether the ascending colon is intraperitoneal or retroperitoneal and describe the blood supply and venous drainage.
- Retroperitoneal.
- Ileocolic and right colic arteries.
- Ileocolic and right colic veins.
State whether the transverse colon is intraperitoneal or retroperitoneal and describe the blood supply and venous drainage.
- Intraperitoneal.
- Middle colic artery.
- Superior mesenteric vein.
State whether the descending colon is intraperitoneal or retroperitoneal and describe the blood supply and venous drainage.
- Retroperitoneal.
- Left colic and superior sigmoid arteries.
- Inferior mesenteric vein.
State whether the sigmoid colon is intraperitoneal or retroperitoneal and describe the blood supply and venous drainage.
- Intraperitoneal.
- Sigmoid arteries.
- Inferior mesenteric vein.
What is the marginal artery of Drummond?
An artery that forms important anastomosis between SMA and IMA. It extends the length of the colon.
What vertebral level is the inferior mesenteric artery found at?
L3.
Name 3 characteristic features of the large intestine that allow it to be distinguished from other abdominal organs.
- Haustrations.
- Tenia coli.
- Appendices epiploicae.
What are appendices epiploicae?
Small pouches of peritoneum filled with fat. They mark where blood vessels enter the bowel to supply the mucosa.
What are tenia coli?
3 strips of longitudinally running muscle on the outer surface of the large intestine.
What are haustrations?
Sacculations produced from where the tenia coli contract to shorten the wall of the bowel.
Where does the hind gut begin and end?
Distal 1/3 of the transverse colon to the anal canal.
What is the innervation of the hind gut?
Sympathetic: least splanchnic nerve (T12). Parasympathetic: S2-4. No somatic innervation.
What artery normally supplies the descending colon?
The left colic artery.
What is the importance of the marginal artery of Drummond?
If there is an occlusion to the IMA, blood can still be supplied to the large intestine via the SMA through this artery.
Give 4 locations where the distal end of the appendix may lie.
- In the pouch of Douglas.
- Behind the caecum.
- Behind the umbilicus.
- Below the liver.
Name the intraperitoneal parts of the large intestine.
Caecum, transverse colon, sigmoid colon.
Give 4 functions of the liver.
- Synthesis of bile.
- Glycogen storage.
- Clotting factor production.
- Detoxification of blood.
What is the liver an embryological derivative of and in which mesentery does it develop?
Derivative of the foregut. Develops in the ventral mesentery.
What structure(s) lie anterior to the liver?
The rib cage and the anterior abdominal wall.
What structure(s) lie superior to the liver?
The diaphragm.
What structure(s) lie posterior to the liver?
Oesophagus, stomach, gall bladder, first part of duodenum. (All are foregut derived organs).
What aspects of the liver does the diaphragmatic surface refer to?
The anterior superior aspects. This surface is smooth and convex.
What aspects of the liver does the visceral surface refer to?
The posterior inferior aspects. It is moulded by the shape of surrounding organs and so is irregular.
Name the 3 liver ligaments.
- The falciform ligament.
- The right and left coronary ligaments.
- The right and left triangular ligaments.
What is the function of the falciform ligament?
To attach the liver to the anterior abdominal wall.
What is found in the free edge of this ligament?
The ligamentum teres (remnant of the umbilical vein).
What is the function of the coronary and triangular ligaments?
They attach the superior surface of the diaphragm to the liver.
Name the 4 lobes of the liver.
- Right.
- Left.
- Caudate.
- Quadrate.
What structures bind the Caudate lobe and where is it located?
The IVC and a fossa produced by the ligamentum venosum. It is located on the upper aspect of the right lobe on the visceral surface.
What structures bind the Quadrate lobe and where is it located?
The gall bladder and a fossa produced by the ligamentum teres. It is located on the lower aspect of the right lobe on the visceral surface.
What divides the liver into the right and left lobes?
The falciform ligament.
What vein supplies the liver with dexoygenated blood?
The hepatic portal vein.
What vein supplies the liver with oxygenated blood?
The hepatic artery proper.
What is the function of the gall bladder?
A temporary storage for bile.
What is the storage capacity of the gall bladder?
30-50ml.
What are the 3 divisions of the gall bladder?
Fundus, body and neck. The neck is where the gall bladder tapers and becomes continuous with the cystic duct.
Briefly describe the biliary tree.
Left and right hepatic ducts = common hepatic duct.
Common hepatic duct + cystic duct = common bile duct. Common bile duct + pancreatic duct = hepatopancreatic ampulla of Vater.
What is it called where the common bile duct and pancreatic duct meet?
The hepatopancreatic ampulla of Vater.
What is the orifice called where bile empties into the duodenum?
The major duodenal papilla.
What sphincter regulates the emptying of bile into the duodenum?
The sphincter of Oddi.
What artery supplies blood to the gall bladder?
The cystic artery.
Does parasympathetic or sympathetic innervation result in contraction of the gall bladder and the secretion of bile?
Parasympathetic.
What is the arrangement anterior to posterior of the ducts, artery and portal vein at the porta hepatis?
Anterior: Common bile duct, hepatic artery, hepatic portal vein.
(DAV)
What is Calot’s triangle?
An anatomic space bounded by the liver superiorly, the cystic duct laterally and the common hepatic duct medially.
What is the cystic artery a branch of?
The right hepatic artery - hepatic artery proper - common hepatic artery - coeliac trunk.
Where is the bare area of the liver?
Under the tendinous part of the right hemi-diaphragm. This area has no peritoneal covering.
What is the surface marking for the gall bladder?
The tip of the 9th costal cartilage. Where the lateral rectus sheath joins the costal margin.
Where do the hepatic veins drain?
Into the IVC.
What are the 3 major branches of the Coeliac trunk?
The left gastric, the splenic and the common hepatic.
What does the left gastric artery supply?
The lesser curvature of the stomach and lower oesophagus.
What branches does the splenic artery give off?
- The short gastric arteries.
- The pancreatic arteries.
- The left gastroepiploic artery.
- 5 branches just before it reaches the Spleen.
What do the short gastric arteries supply?
The greater curvature of the stomach.
What does the left gastroepiploic artery supply? What does anastomose with?
It supplies the greater curvature of the stomach. It anastomoses with the right gastroepiploic artery.
Name the 2 branches of the common hepatic artery.
- Proper hepatic artery.
2. Gastroduodenal artery.
Name the 2 branches of the Gastroduodenal artery.
- Right gastroepiploic artery (supplies greater curvature of the stomach).
- Superior pancreaticoduodenal artery (supplies head of pancreas).
Name the 3 branches of the proper hepatic artery?
- Right hepatic artery.
- Left hepatic artery.
- Right gastric artery.
What does the right gastric artery supply?
The lesser curvature of the stomach.
What is a branch of the right hepatic artery?
The cystic artery (supplies the gall bladder).
Name the 4 divisions of the Duodenum.
- Superior.
- Descending.
- Inferior.
- Ascending.
Where in the duodenum are ulcers most likely? And which artery would they affect?
Most likely in the superior duodenum (1st part). If the ulcers erode through the posterior wall they may effect the gastroduodenal artery and cause haemorrhage.
What does the descending portion of the Duodenum lie posteriorly and anteriorly to?
Posteriorly to transverse colon. Anteriorly to the right kidney.
What vessels lie anteriorly to the inferior part of the duodenum? (3rd part)
The superior mesenteric artery and vein.
Is the duodenum retroperitoneal or intraperitoneal?
The duodenal cap is intraperitoneal but the rest of the duodenum is retroperitoneal.
Is the pancreas retroperitoneal or intraperitoneal?
The tail is intraperitoneal but the rest of the pancreas is retroperitoneal.
Name the 5 parts of the Pancreas.
- The head.
- The uncinate process.
- The neck.
- The body.
- The tail.
What does the tail of the pancreas lie in close proximity to?
The hilum of the spleen.
Why can diseases of the pancreas spread to adjacent tissues?
Because it isn’t contained within a capsule.
What is the blood supply to the head of the pancreas?
The superior and inferior pancraticoduodenal arteries.
What is the superior pancraticoduodenal artery a branch of?
The gastroduodenal artery.
What is the inferior pancraticoduodenal artery a branch of?
The SMA.
What is the blood supply to the rest of the pancreas?
Pancreatic branches of the splenic artery.
What is the venous drainage of the pancreas?
The head drains into the SMV (drains into hepatic portal vein). the pancreatic veins drain the rest of the pancreas (these drain into the splenic vein).
What is the function of the spleen?
In an adult it functions mainly as a blood filter, removing old RBC’s from circulation.
Is the spleen intraperitoneal or retroperitoneal?
Intraperitoneal.
What ligaments of the greater omentum connect the spleen to the stomach and kidney?
Gastrosplenic and Splenorenal.
How far away is the major duodenal papilla from the pylorus of the stomach?
5cm.
What is the embryological significance of the major duodenal papilla?
It marks the junction between the foregut and the midgut.
What is the importance of the plicae circularis?
They increase the intestinal SA available for absorption.
What are gyri?
Rolls of cerebral cortex.
What are sulci?
Grooves/depressions between gyri.
What sulcus separates the frontal lobe from the parietal?
The central sulcus.
What sulcus separates the temporal lobe from the frontal and parietal lobe?
The lateral sulcus (sylvian fissure).
Define insula.
A portion of cerebral cortex folded deep in the lateral sulcus; forms the floor of the lateral sulcus.
What divides the brain into right and left hemispheres?
The deep longitudinal fissure.
What white matter structure holds the hemispheres together?
The corpus callosum.
Within what lobe is broca’s area located?
The dominant (usually left) frontal lobe.
What is the function of Broca’s area?
Language production.
Within what lobe is Wernicke’s area located?
The dominant (usually left) temporal lobe.
What is the function of Wernicke’s area?
It is involved in the comprehension of written and spoken language.
Where is the primary motor cortex located?
In the pre-central gyrus of the frontal lobe.
What are the functions of the frontal lobes?
Motor function, problem solving, judgement, personality, social and sexual behaviour.
What is the pre-frontal cortex responsible for?
Higher cognitive functions e.g. personality.
Where is the primary somatosensory cortex located?
In the post-central gyrus of the parietal lobe.
What are the functions of the parietal lobes?
Somatosensory function. The dominant lobe is involved in perception, interpretation of sensory information, language and mathematical operations. The non dominant lobe has visiospatial functions.
What cortex are located in the occipital lobes?
Primary visual and vision association cortex.
What cortex is located in the temporal lobe?
Primary auditory cortex.
What are the functions of the temporal lobe?
Hearing, language comprehension (wernicke’s area). It also contains the hippocampus and amygdala.
What is the function of the hippocampus?
Important in the formation of long term memories.
What are the motor and sensory homunculi?
Proportional somatotopical representations of how much of the cortex innervates certain body parts.
How many horns does the lateral ventricle have and what are they called?
3 horns.
Anterior, posterior and inferior.
What is the foramen between the lateral ventricles and 3rd ventricle called?
The foramen of Munro.
What is the foramen between the 3rd and 4th ventricle called?
The cerebral aqueduct.
What are the foramen called that connect the 4th ventricle to the subarachnoid space?
The foramina of luschka (lateral) and the foramen of magendie (medial).
Where is choroid plexus located?
Along the choroid fissure of the lateral ventricle and in the roof of the 3rd and 4th ventricle.
How is CSF reabsorbed into dural venous sinuses?
Via arachnoid granulations. CSF drains through the endothelium into the dural venous sinus.
What are the 4 anatomical divisions of the corpus callosum?
- Rostrum.
- Genu.
- Body.
- Splenium.
Which anatomical division of the corpus callosum lies most posteriorly?
The splenium.
What gyrus lies immediately above the corpus callosum?
The cingulate gyrus.
What structure forms the roof of the lateral ventricles?
The corpus callosum.
What are commissural fibres?
Fibres linking similar functional areas of the two hemispheres together e.g. the corpus callosum is composed of commissural fibres.
What is the brainstem composed of?
The midbrain, pons and medulla oblangata.
What structure divides the midbrain into dorsal and ventral parts?
The cerebral aqueduct.
What forms the dorsal midbrain?
The tectum.
What is the tectum of the midbrain composed of?
The inferior and superior colliculi.
What forms the ventral midbrain?
The cerebral peduncle.
What is the cerebral peduncle of the midbrain composed of?
A dorsal tegmentum and a ventral crus cerebri.
What structure divides the tegmentum from the crus cerebri?
The substantia nigra.
What are the crus cerebri?
White matter bundles emerging from the cerebral hemispheres.
What is the attachment between the midbrain and cerebellum called?
The superior cerebellar peduncles.
What is the function of the pineal gland?
Synthesises melatonin.
What is the midline sulcus on the ventral surface of the pons called?
The basilar sulcus (where the basilar artery lies).
What is the sulcus called that forms the caudal border of the pons?
The bulbopontine sulcus.
What is the medullary striae?
Ponto-cerebellar fibres that divide the floor of the 4th ventricle into a rostral pontine half and a caudal medullary half.
What is the obex?
The inferior apex of the rhomboid fossa.
What are the midline fissures of the medulla called?
- The anterior median fissure (ventral).
- The posterior median fissure (dorsal).
What is the medullary olive?
An eminence caused by the presence of the inferior olivary nucleus underneath. Located lateral to the ventrolateral sulcus.
What lies lateral to the posterior median sulcus?
The gracile tubercle (dorsal column nuclei that participate in the sensation of fine touch and proprioception of the lower body).
What lies lateral to the gracile tubercle?
The cuneate tubercle (dorsal column nuclei that participate in the sensation of fine touch and proprioception of the upper body).
What are the functions of the kidneys?
They act to filter and excrete waste products from the blood. They are also responsible for H2O and electrolyte balance.
What are the posterior relations to the kidneys?
Diaphragm, psoas major, quadratus lumborum and transversus abdominis.
What are the anterior relations to the right kidney?
Liver and duodenum, coils of intestine.
What are the anterior relations to the left kidney?
Stomach, spleen, pancreas, coils of intestine.
What is found at the renal hilum?
Renal arteries and veins, ureter, nerves and lymphatics.
Which kidney is often positioned lower in the abdomen and why?
The right kidney, this is due to the presence of the liver.
What are the renal arteries a branch of?
The abdominal aorta just below the SMA.
Which renal artery is longer?
The right renal artery, this is due to the position of the aorta being slightly to the left.
Which artery crosses the IVC posteriorly?
The right renal artery.
Describe the branching of the renal artery.
Renal artery -> interlobar artery -> arcuate artery -> interlobular artery -> afferent arteriole.
Where do the renal veins drain?
Into the IVC.
How would you describe the shape of the:
a) right adrenal gland?
b) left adrenal gland?
a) Tetrahedral.
b) Crescent-shaped.
Which adrenal gland does the IVC lie anteriorly to?
The right adrenal gland.
What are the 3 main layers of an adrenal gland?
- An outer connective tissue capsule.
- A cortex.
- A medulla at the centre.
Adrenal glands: What are the 3 layers of the cortex?
- Zona glomerulus.
- Zona fasciculata.
- Zona reticularis.
Adrenal glands: What cells are contained within the medulla and what do they secrete?
Chromaffin cells - they secrete catecholamines e.g. adrenaline. This is a ‘fight or flight’ response.
What are the 3 arteries that supply the adrenal glands?
- Superior adrenal artery.
- Middle adrenal artery.
- Inferior adrenal artery.
What is the superior adrenal artery a branch of?
The inferior phrenic artery.
What is the middle adrenal artery a branch of?
The abdominal aorta.
What is the inferior adrenal artery a branch of?
The renal arteries.
What does the right adrenal vein drain into?
The IVC.
What does the left adrenal vein drain into?
The left renal vein (and then into the IVC).
What section of the spine is found in the posterior abdominal wall?
The lumbar section.
What muscle lies superficially to psoas major?
Quadratus lumborum.
What is the origin of quadratus lumborum?
Iliac crest and the iliolumbar ligament.
What is the insertion of quadratus lumborum?
The transverse processes of L1 to L4 and the 12th rib.
What is the action of quadratus lumborum?
Extension and flexion of the vertebral column.
What is the innervation of quadratus lumborum?
T12-L4 nerves.
What is the origin of psoas major?
T12-L5 vertebrae.
What is the insertion of psoas major?
The lesser trochanter of the femus.
What is the action of psoas major?
Flexion of the hip.
What is the innervation of psoas major?
L1-3 nerves.
What nerves lies on the anterior surface of psoas major?
The genitofemoral nerve.
Where does the femoral branch of the genitofemoral nerve go?
It passes under the inguinal ligament and supplies sensory innervation to the inner thigh.
Where does the genital branch of the genitofemoral nerve go?
It passes through the deep inguinal ring to enter the inguinal canal. It supplies the cremaster muscle.
Why can renal tumours become very large before invading adjacent structures?
The tumour has to grow through multiple tough layers: fibrous capsule, perirenal fat, renal fascia and pararenal fat.
What vein does the right gonadal vein drain into?
The IVC.
What vein does the left gonadal vein drain into?
The left renal vein (and then the IVC).
Where would you palpate an abdominal aortic aneurysm?
In the epigastrium, above the umbilicus.
What is the origin of psoas major?
T12-L5.
What is the insertion of psoas major and iliacus muscles?
Lesser trochanter of femur.
What is the origin of iliacus muscle?
Iliac fossa and anterior inferior iliac spine.
What is the innervation of iliacus muscle?
Femoral nerve (L2-4).
What nerve lies in the groove between the iliacus and psoas major?
The femoral nerve.
What nerve emerges from psoas major medially?
Obturator nerve.
What does the femoral nerve give motor innervation to?
The anterior thigh muscles that flex the hip and extend the knee.
What is the action of iliacus?
Flexion of the hip.
What does the femoral nerve give sensory innervation to?
Cutaneous branches pass to the antero-medial thigh. The terminal branch, saphenous nerve, supplies the medial side of the leg and foot.
What are the nerve roots for the femoral and obtruator nerves?
L2-L4.
What does the obtruator nerve give motor innervation to?
The medial thigh muscles inolved in adduction.
