Actual Low Yield Anatomy Supplement

Question 1

Other than the bronchial circulation, what other structure contributes to deoxygenation of blood in the left atrium?

Answer 1

Small cardiac (Thebesian) veins also drain into left atrium

Question 2

What are the key artery / vein pairings of the heart?

Answer 2

Left anterior descending artery - great cardiac vein

Posterior descending artery - middle cardiac vein

Right coronary artery (posteriorly) - small cardiac vein

Proximal right coronary artery - anterior cardiac veins (right ventricle drainage)

Circumflex artery - posterior vein of left ventricle

Question 3

What germ layer is the adrenal cortex derived from?

Answer 3

Mesoderm

Question 4

What is the epiploic foramen? What are its anterior, superior, inferior, and posterior boundaries?

Answer 4

The opening of the lesser sac into the greater sac.
Anterior: Hepatoduodenal ligament
Superior: Caudate lobe of liver
Inferiorly: First part of duodenum
Posteriorly: Inferior vena cava and right crus of diaphragm

Question 5

Where do the left and right gastric arteries anastamose?

Answer 5

Within the lesser omentum. More specifically, within the hepatogastric ligament (part of lesser omentum, along with hepatoduodenal ligament)

Question 6

What is the relative frequency of slow waves in stomach vs duodenum vs ileum?

Answer 6

Stomach - 3 waves / min (slowest)
Duodenum - 12 waves / min (fastest)
Ileum - 8-9 waves / min

This is the intrinsic rate of the interstitial cells of Cajal in bringing smooth muscle cells closer to and away from threshold

Question 7

What is the purpose of a slow wave?

Answer 7

When they are actively depolarizing / moving towards threshold, they increase the probability that neurohormonal stimulation will cause contraction
-> slow waves are NOT action potentials, just modifications of the intrinsic excitability of the smooth muscle

Question 8

What are the circumferential submucosal folds in the small intestine? What is their function?

Answer 8

Plicae circularis

These serve to increase the surface area of the small intestine along with the mucosal folds (villi)

Only plicae semilunares (not full circles) are seen in colon, and there are NO villi

Question 9

What are the three primary branches of the celiac trunk?

Answer 9

1. Left gastric
2. Splenic
3. Common hepatic

Question 10

Where do the left and right gastroepiploic arteries come from?

Answer 10

Left - splenic artery

right - gastroduodenal artery

Question 11

What supplies blood to the gall bladder?

Answer 11

Cystic artery, which is a branch of the right hepatic artery (branch of proper hepatic, from common hepatic)

Question 12

What gives rise to the pancreaticoduodenal arteries?

Answer 12

branches of the gastroduodenal arteries (which is a branch of the common hepatic)

Question 13

Which zone does the most oxidative metabolism, gluconeogenesis, transamination, protein, cholesterol, and urea synthesis? Why?

Answer 13

Zone 1 - closest to blood inflow, has highest oxygen content and numerous mitochondria

Question 14

What are zone 3 hepatocytes important for? Where in the cell do these processes occur?

Answer 14

Have lower oxygen content, primarily function in biotransformation - phase 1 and phase 2 reactions

Phase 1 reactions - Smooth ER

Phase 2 - conjugation reactions occur in cytosol

Question 15

What zone of hepatocytes are most susceptible to drugs / toxins / hypoxia / ischemia?

Answer 15

Hypoxia / Ischemia - zone 3, furthest from blood supply

Drugs / toxins - Zone 3 as well, due to phase 1 reactions (ethanol and acetaminophen toxicity causes centrilobular necrosis)

Question 16

What zone of the liver is most susceptible to viral hepatitis, ingested toxins, and hemochromatosis?

Answer 16

Zone 1 -> sees the blood flow the earliest

These are toxins which do NOT require bioactivation

Question 17

What is the function of the ilioinguinal nerve?

Answer 17

Branch of L1 - Accompanies the spermatic cord thru the superficial inguinal ring to supply sensation to the anterior scrotum and upper medial thigh

Question 18

What forms the major structural integrity of the lower esophageal sphincter?

Answer 18

The diaphragmatic crura, which wrap around the esophagus at the T10 level

Question 19

What are the major proteins produced by eosinophils?

Answer 19

Histaminase - decrease inflammatory response
Major basic protein
Eosinophil peroxidase - (similar to MPO)
Eosinophil cationic protein - destruction of helminths, ribonuclease activity
Eosinophil-derived neurotoxin - ribonuclease activity

Question 20

What chemotactic factor to mast cells possess?

Answer 20

Eosinophilic chemotactic factor

Question 21

Which kidney is typically taken for kidney transplant surgery and why?

Answer 21

Left kidney -> has a longer renal vein so it can be easier connected in the recipient

Question 22

What is a lobe vs a lobule of the kidney?

Answer 22

Lobe - a grossly apparent medullary pyramid with its associated cortex, separated by cortical columns

Lobule - group of nephrons draining into a common collecting duct

Question 23

What is nutcracker syndrome?

Answer 23

When the left renal vein becomes cause between SMA and aorta

-> leads to fluid backup / varicocele

Question 24

How is overactive bladder treated?

Answer 24

Via solifenacin, an anticholinergic agent to block the acetylcholine receptor in detrusor, since PANS is overworking and causing overcontractility.

Solifenacin is in the same class as tolterodine / oxybutynin

Question 25

What is the course of PANS to the pelvis?

Answer 25

Preganglionic cell body: S2-S4 in intermediate gray matter
Preganglionic axons: pelvic splanchnics, passing through pelvic plexus (inferior hypogastric) to subsidiary plexuses around branches of internal iliac to walls of viscera
Postganglionic cell body: terminal ganglion in wall of viscera
Postganglionic axons: innervate smooth muscle, glands in bladder, rectum, prostate, seminal vesicles, ejaculatory ducts, urethra, uterus, and erectile tissue

Question 26

Are the Sertoli cells or Leydig cells temperature sensitive? What barrier do they form?

Answer 26

Sertoli cells -> varicocele or cryptorchidism will cause decreased sperm production and inhibin B

Form the blood-testis barrier to protect developing sperm from autoimmune attack