Lecture 24

Question 1

Spleen

Answer 1

Largest lymphatic organ; develops in dorsal mesentery of stomach (not an embryological derivative of gut tube); lies against diaphragm in left hypochondriac region along the long axis of ribs 9-11

Question 2

Gastrosplenic (Gastrolienal) Ligament

Answer 2

Attaches spleen to stomach; contains left gastroepiploic artery and vein; short gastric arteries and veins

Question 3

Phrenicosplenic (Phrenicolienal) Ligament

Answer 3

Attaches spleen to diaphragm

Question 4

Lienorenal Ligament

Answer 4

Attaches spleen to left kidney

Question 5

Vascular Supply of the Spleen

Answer 5

Splenic artery via 4 branches: superior polar, superior middle, inferior middle, and inferior polar

Question 6

Impressions of the Spleen

Answer 6

Stomach, large intestine, and kidney

Question 7

Functions of the Pancreas

Answer 7

Exocrine function is to produce pancreatic juice that aids in digestion (digestive enzymes and bicarbonate ions); endocrine function is to produce hormones (insulin and glucagon)

Question 8

Pancreas

Answer 8

Divided into 4 parts (head, neck, body, tail); located in epigastric and left hypochondriac regions; blood supplied by branches of splenic artery and superior/inferior pancreaticoduodenal arteries

Question 9

Head of Pancreas

Answer 9

Lies in curvature of duodenum; lies anterior to inferior vena cava; transversed by common bile duct; contains uncinate process (posteromedial projection from head of pancreas)

Question 10

Neck of Pancreas

Answer 10

Constricted where crossed posteriorly by superior mesenteric artery

Question 11

Tail of Pancreas

Answer 11

Ends at hilus of spleen

Question 12

Body of Pancreas

Answer 12

Triangular in cross-section; extends across midline across aorta and left renal vein; anterior surface is covered by peritoneum and lies in floor of omental bursa; posterior surface is devoid of peritoneum and contacts aorta, superior mesenteric artery, left kidney, and left suprarenal gland

Question 13

Main Pancreatic Duct

Answer 13

Begins in tail of pancreas; runs through pancreatic parenchyma; exits gland at head; turns inferiorly and meets bile duct

Question 14

Hepatopancreatic Ampulla

Answer 14

Junction of main pancreatic duct and common bile duct; empties into duodenum via major duodenal papilla

Question 15

Accessory Pancreatic Duct

Answer 15

Drains uncinate process and inferior head of pancreas; empties into duodenum via minor duodenal papilla

Question 16

Duodenum

Answer 16

Section of small intestine extending from pylorus to jejunum; surrounds head of pancreas; retroperitoneal; begins at right of midline at level of lumbar vertebra 1 and ends at left of midline at level of lumbar vertebra 2; divided into four parts (superior part, L1, descending part, L1-3, horizontal part, L3, and ascending part, L2-3)

Question 17

Superior Part of Duodenum

Answer 17

First part distal to pylorus

Question 18

Descending Part of Duodenum

Answer 18

Consists of major duodenal papilla and minor duodenal papilla

Question 19

Major Duodenal Papilla

Answer 19

Empties hepatopancreatic ampulla into duodenum; expanded area proximal to major duodenal papilla; opening of common bile duct and main pancreatic duct where common bile duct and main pancreatic duct unite; sphincter of oddi controls emptying of common bile duct

Question 20

Minor Duodenal Papilla

Answer 20

Empties accessory pancreatic duct into duodenum

Question 21

Horizontal Part of Duodenum

Answer 21

Travels to the left

Question 22

Ascending Part of Duodenum

Answer 22

Meets with jejunum at duodenojejunal junction

Question 23

Blood Supply of Duodenum

Answer 23

Gastroduodenal artery via smaller named arteries; superior mesenteric artery via smaller named artereis

Question 24

Jejunum and Ileum

Answer 24

Begins at duodenojejunal flexure in upper left quadrant and ends at ileocecal junction in lower right quadrant; approximately 20 feet in length; attached to posterior abdominal wall by mesentery (proper) of small intestine that is 15 inches long where it attaches to the posterior abdominal wall

Question 25

Jejunum

Answer 25

Deeper red, thicker walled, and shorter than ileum; contains long vasa recta; blood from superior mesenteric artery; venous drainage via superior mesenteric vein

Question 26

Tenia Coli of Large Intestine

Answer 26

Thickened bands of smooth muscle

Question 27

Haustra of Large Intestine

Answer 27

Pouches between tenia

Question 28

What does the large intestine consist of?

Answer 28

Tenia coli, haustra, epiploic appendages, cecum, appendix, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum

Question 29

Cecum and Appendix

Answer 29

Cecum is large, blind-ended pouch continuous with ascending colon; ileocecal orifice with ileocecal valve

Question 30

McBurney’s Point

Answer 30

2/3 distance from umbilicus to ASIS

Question 31

Ascending Colon

Answer 31

From cecum to right colic (hepatic) flexure

Question 32

Transverse Colon

Answer 32

From right colic flexure (hepatic) to left colic flexure (splenic); suspended by transverse mesocolon; arterial supply via middle colic artery from superior mesenteric artery

Question 33

Descending Colon

Answer 33

From left colic flexure to pelvic brim (sigmoid colon); mostly covered by peritoneum but posterior wall is fused to posterior abdominal wall; arterial supply via branch from inferior mesenteric artery

Question 34

Sigmoid Colon

Answer 34

Begins at pelvic brim; “S” shaped; becomes continuous with rectum at sacral vertebra 3; suspended by sigmoid mesocolon; arterial supply via inferior mesenteric artery

Question 35

Rectum

Answer 35

Fixed terminal portion of colon; begins at level of sacral vertebra 3; follows curvature of sacrum and coccyx

Question 36

Internal Anal Sphincter

Answer 36

Thick ring of circular smooth muscle; surrounds upper part of anal canal; controlled by reflexively and involuntarily by ANS; parasympathetic system promotes relaxation; sympathetic system promotes contraction

Question 37

External Anal Sphincter

Answer 37

Three rings of skeletal muscle; extends entire length of anal canal; controlled voluntarily via branches of pudendal nerve

Question 38

Anal Columns

Answer 38

5-10 longitudinal folds of mucosa in upper half of canal

Question 39

Pectinate Line

Answer 39

Marks junction between endoderm portion of anal canal and ectoderm portion of anal canal; marks division between visceral and somatic (arterial, venous, lymphatic, and nerve supply)