ANA124 ABDOMINAL MIDTERM: A5

what is the cortex

the outer layer if the kidney

what does the cortex contain

contains nephrons and blood vessels

what are nephrons

parts of the kidney responsible for..

• filtering blood 

• producing urine

function of the cortex

filters blood + starts the formation of urine

• separates waste from useful substances

• main site of filtration

what is the medulla

inner region of the kidney 

what does the medulla contain

renal pyramids + renal columns + collecting ducts (calyses)

function of the medulla

aids in water reabsorption 

• maintains hydration + electrolyte balance

• concentrates urine 

what does it mean to concentrate urine

to make the urine less watery and more packed with waste

• ESSENTIALLY.. less water, more waste = darker urine

• maintains fluid balance

what are the renal pyramids

cone-shaped structures (triangular structures) in the medulla

what do do the renal pyramids contain

nephrons + collecting ducts

function of the renal pyramids

to concentrate urine by collecting and transporting it through nephrons + ducts

what are the renal columns

tissue found between the renal pyramids which support the cortex

function of the renal columns

• support the renal pyramids

• facilitate blood flow 

  • to the medulla + renal pyramids 

• stabilizes the kidney’s internal structure (the cortex) 

what are the minor calyxes

small, cup -shaped structures

location of the minor calyxes

at the tip of each renal pyramid

functon of the minor calyxes

to collect urine from renal pyramids

what are the major calyxes

larger structure that is formed when the minor calyxes merge together 

• urine channels into the renal pelvis

function of the major calyxes

to collect urine from minor calyxes → channel it into the renal pelvis

what is the renal pelvis

funnel-shaped structure

function of the renal pelvis

to collect urine from the major calyxes → ureter → bladder

what is the renal hilum (hilus)

area on the medial surface of the kidney

• the entry + exit point 

function of the renal hilum

to allow blood vessels, nerves, + ureters to enter and exit the kidney

• for the.. renal A, renal V, renal pelvis 

• controls the flow of blood + urine both in and out the kidney 

relationship between the ureter, renal V + renal A

1. renal pelvis (most posterior)

2. renal artery (in the middle)

3. renal vein (most anterior)

location of the renal artery

it branches off of the abdominal aorta → renal hilum

function of the renal artery

carries oxygenated + unfiltered blood from aorta → kidneys

location of the renal vein

leaves the kidney through the renal hilum

function of the renal vein

drains deoxygenated + filtered blood from the kidneys → IVC → heart

location of the abdominal aorta

the main artery that runs down the posterior abdomen

• extends from the diaphragm → L4

function of the abdominal aorta

distributes oxygenated blood to the abdominal organs + lower limbs

location of the inferior vena cava (IVC)

runs alongside the abdominal aorta

• extends from L5 → diaphragm → RA of the heart

function of the inferior vena cava (IVC)

returns deoxygenated blood from the lower body → heart

location of the thoracic aorta

a continuation of the arch of aorta → passes through the diaphragm at T12

function of the thoracic aorta

supplies oxygenated blood to the thoracic wall + lungs + esophagus

relationship between the abdominal + thoracic aorta

the thoracic aorta transitions into the abdominal aorta

location of the celiac trunk

arises from the abdominal aorta (~ around T12)

function of the celiac trunk

supplies oxygenated blood to the..

• stomach

• duodenum

• pancreas

• spleen

• liver

location of the superior mesenteric artery (SMA)

arises from the abdominal aorta (~ around L1)

function of the superior mesenteric artery (SMA)

supplies oxygenated blood to the..

• small intestine (jejunum/ileum)

• area between the ileum + cecum

• appendix

• ascending colon

• proximal 2/3 of the transverse colon

location of the inferior mesenteric artery (IMA)

arises from the abdominal aorta (~ around L3)

function of the inferior mesenteric artery (IMA)

supplies oxygenated blood to the..

• distal 1/3 of the transverse colon 

• descending colon

• sigmoid colon

• rectum + anal canal

what is the anatomical nutrcracker

describes how the SMA and aorta form a tight angle + how the left renal vein gets caught between them

what does the anatomical nutcracker tell us

that the renal vein lies between the abdominal aorta (posteriorly) and SMA (anteriorly)

• causing potential compression = renal vein is “squished”

main branches of the celiac trunk

1. common hepatic artery (to the right)

2. left gastric artery (in the middle)

3. splenic artery (to the left)

branches of the common hepatic artery (+ what they supply)

1. gastro-duodenal artery - greater curvature of the stomach, duodenum, pancreas

2. right gastric artery - lesser curvature of the stomach

3. hepatic artery proper - liver

branches of the gastro-duodenal artery (+ what they supply)

1. right gastro-omental artery - greater curvature of the stomach

2. superior pancreatico-duodenal artery - head of pancreas + duodenum 

branches of the hepatic artery proper (+ what they supply)

1. right hepatic artery - right lobe

2. left hepatic artery = left lobe

where does the splenic artery run

runs along the superior part of the pancreas + towards the left

branches of the splenic artery (+ what they supply)

1. short gastric artery - fundus of the stomach

2. left gastro-omental artery - greater curvature of the stomach

branches of the superior mesenteric artery (+ what they supply)

1. jejunal/ileal arteries - jejunum + ileum 

2. ileocolic artery - end of ileum + cecum + 1st part of ascending 

3. right colic artery - ascending colon

4. middle colic artery - proximal 2/3 of transverse colon 

branches of the ileocolic artery (+ what they supply)

appendicular artery - appendix 

branches of the inferior mesenteric artery (+ what they supply)

1. left colic artery - distal 1/3 of transverse colon + descending colon

2. sigmoid artery - sigmoid colon

3. rectal artery - rectum + upper anal canal

what is the portal vein system 

network of veins that drains blood from the gastrointestinal tract + organs → liver

how does the portal vein system work

1. 1st capillary bed → digestive organs absorb nutrients from food

2. blood enters portal vein through..

   1. SMV

   2. IMV

   3. splenic v - which joins the splenic v

3. 2nd capillary bed → liver (hepatic sinusoids) → filters blood + adjusts nutrients

4. blood leaves via hepatic veins → IVC → heart 

location of the superior mesenteric vein (SMV)

goes behind the pancreas + alongside the SMA

function of the superior mesenteric vein (SMV)

drains blood (with nutrients) from everything the SMA supplies

• joins w/ the splenic vein → portal vein

location of the splenic vein

goes behind the pancreas

function of the splenic vein

• drains the spleen, pancreas + stomach

• joins w/ the SMV → portal vein 

• receives blood from the IMV

location of the inferior mesenteric vein (IMV)

begins in the rectum/sigmoid colon

function of the inferior mesenteric vein (IMV)

• drains everything the IMA supplies

• joins w/ the splenic vein → portal vein 

flowchart of the venous drainage in the digestive system

1. digestive organs (1st capillary bed)

2. SMV, IMV → splenic vein

3. portal vein 

4. hepatic sinusoids (2nd capillary bed) → liver

5. hepatic veins → IVC

location of the gonadal vein

veins that come from the gonads → either into the IVC (males) or left renal vein (females)

function of the gonadal vein

• carries deoxygenated blood from the gonads (ovaries or testes) → heart

• regulates blood flow + temperature 

location of the arterial arcades (of the SMA)

• found within the mesentary of the small intestine

• between the SMA and intestinal wall 

what are the arterial arcades formed by

formed by the jejunal/ileal branches of the SMA

function of the arterial arcades

loops of small arteries that connect neighbouring branches of the SMA

• continuous blood supply → intestines even if 1 branch is blocked