Anatomy Flashcards
Define catabolism?
Nutrients from the environment are broken down to provide energy that cells need to function
What does catabolism require?
O2
organic molecules (fats, carbs, proteins)
Define anabolism?
Nutrients from the environment are used as raw materials to synthesize essential compounds
What are the 4 layers from deep to superficial?
mucosa
submucosa
muscularis externa
serosa
What generally makes up the epithelium?
- Stratified squamous epithelium
- Simple columnar epithelium
- Lamina propria
Describe the stratified squamous epithelium of the mucosa?
located in areas of high stress
-oral cavity
-pharynx
-esophagus
Describe the simple columnar epithelium of the mucosa?
located in areas with lower amounts of stress
-stomach
-small intestine
-colon
*contains mucus cells
Describe the lamina propria of the mucosa?
Layer of connective tissue
-blood/lymph vessels
-sensory nerves
-smooth muscle cells
-lymphoid tissue
-secretory cells of mucus glands
What types of cells are part of the simple columnar epithelium?
Enteroendocrine cells
-scattered amongst the columnar cells
-secrete hormones which help coordinate the activities of digestion
Pilcae
-transverse folds in the digestive tract which help to increase the surface area for absorption
Describe the submucosa?
Layer of dense irregular connective tissue
-binds the mucosa to the muscularis externa
-contain blood/lymph vessels and exocrine glands which secrete digestive enzymes
What is contained within the submucosa?
submucosal plexus:
-network of nerve fibers and neurons
-sensory, sympathetic and parasympathetic
Describe the muscularis externa?
Dominated by smooth muscle; play a role in mechanical processing and movement of materials through the digestive tract
What plexus is contained within the muscularis externa?
Myenteric plexus
-network of parasympathetic ganglia, sensory neurons, interneurons, and sympathetic postganglionic fibers
Parasympathetic - increase muscular tone and activity
Sympathetic - promote muscular inhibition and relaxation
Describe the serosa?
Serous membrane which covers the muscularis externa
Define gastroparesis?
Paralysis of the stomach and GI tract
-the submucosal and myenteric plexus both have autonomic innervation - both will slow down
-results in failure to empty due to decreased motility
What are the etiologies of gastroparesis?
diabetic autonomic neuropathy
anticholinergic drugs
Vagotomy
Signs and symptoms of gastroparesis?
Postprandial fullness
N/V
Anorexia
Bloating
Weight loss due to anorexia
What membranes are found within the peritoneum/peritoneal cavity?
visceral peritoneum - covers the organs in the peritoneal cavity
parietal peritoneum - lines the inner surface of the body wall
What is the function of peritoneum/peritoneal cavity?
production of peritoneal fluid
-provides essential lubrication in the peritoneal cavity
-reduces friction
Define ascites?
increased fluid in the peritoneal cavity
-liver disease
-kidney disease
-heart failure
What are the 4 primary abdominal muscles from superficial to deep?
external oblique
internal oblique
rectus abdominus
transverse abdominus
What are the actions and innervations of the external oblique?
actions:
-compress abdomen
-depress ribs
-flex spine
innervations:
-intercostal nerve
-iliohypogastric nerve
-ilioinguinal nerve
What are the actions and innervations of the internal oblique?
Actions:
-compress the abdomen
-depress ribs
-flex spine
innervations:
-intercostal nerve
-iliohypogastric nerve
-ilioinguinal nerve
What are the actions and innervations of the rectus abdominus?
Actions:
-compress abdomen
-depress ribs
-flex ribs
Innervation:
-intercostal nerves T7-T12
What are the actions and innervations of the transverse abdominus?
Action:
-compress abdomen
Innervations:
-intercostal nerve
-iliohypogastric nerve
-ilioinguinal nerve
Describe the abdominal aorta?
-begins inferior to diaphragm
-descends slightly to the left of the vertebral column
-posterior to the peritoneal cavity
What is the function of the abdominal aorta?
delivers blood to all abdominopelvic organs/structures:
-branches to the visceral organs UNPAIRED
-branches to the body wall, kidneys, and bladder PAIRED
What are the unpaired arteries that the AA gives rise to?
celiac trunk
superior mesenteric artery
inferior mesenteric artery
What are the branches of the celiac trunk that the AA gives rise to?
left gastric artery
splenic artery
common hepatic artery
What does the left gastric artery supply?
stomach
esophagus
What does the splenic artery give rise to/supply?
left gastroepiploic artery
-spleen
-stomach
pancreatic arteries
-pancreas
What does the common hepatic artery gives rise to?
hepatic proper artery
right gastric artery
cystic artery
gastroduodenal artery
right gastroepiploic artery
superior pancreaticoduodenal arteries
What does the hepatic proper artery supply
liver
What does the right epigastric artery supply?
stomach
What does the cystic artery supply
gall bladder
What does the gastroduodenal artery supply
duodenum
What does the right gastroepiploic artery supply
duodenum
What do the superior pancreaticoduodenal arteries supply
duodenum
What does the superior mesenteric artery supply?
inferior pancreaticoduodenal artery
intestinal arteries
right colic artery
middle colic artery
Ileocolic arteries
What does the inferior pancreaticoduodenal artery supply
pancreas
What do the intestinal arteries supply
small intestine
What arteries supply the large intestine?
right colic
middle colic
ileocolic
What does the inferior mesenteric artery give rise to?
left colic artery
sigmoid arteries
rectal arteries
What does the left colic artery supply?
terminal colon
What do the sigmoid arteries supply?
terminal colon
What do the rectal arteries supply?
rectum
Describe intestinal ischemia?
range of conditions that happen when blood flow to intestine slows or stops
-blocked artery
-low blood pressure
Where foes the hepatic portal system begin and end?
begins in the capillaries of the digestive organs
ends in the liver sinusoids
What is the portal vessel and portal system?
Portal vessel: blood vessel connecting two capillary beds
Portal system: network of portal vessels
What is the difference between blood flowing in the hepatic portal system vs other systemic veins?
-contains substances absorbed from the stomach and intestines
-Delivers these substances to the liver for storage, metabolic conversion, or excretion
Describe the hepatic portal vein?
Largest vessel in the hepatic portal system
Delivers blood to the liver
Receives blood from 3 large veins draining organs in the peritoneal cavity
Which 3 veins drain into the hepatic portal vein?
inferior mesenteric vein
splenic vein
superior mesenteric vein
Describe the inferior mesenteric vein and its drainage into the hepatic portal vein?
collects blood from inferior large intestine
-left colic vein
-superior rectal veins
drains descending colon, sigmoid colon, and rectum
Describe the splenic vein and its drainage into the hepatic portal vein?
formed by the union of the inferior mesenteric vein, veins from the spleen, and veins from the lateral border of the stomach
-left gastroepiploic vein (lateral border of stomach)
-pancreatic vein (drains the pancreas)
Which veins drain into the superior mesenteric vein to be drained into the hepatic portal vein?
right gastroepiploic - stomach
intestinal - small intestine
pancreaticoduodenal - small intestine
ileocolic - 2/3 L.I.
right colic - 2/3 L.I.
middle colic - 2/3 L.I
As the hepatic portal vein proceeds, it receives blood from which vessel?
left and right gastric veins
-medial border of stomach
cystic veins
-gallbladder
Where does the hepatic portal vein end up?
passes through the liver sinusoids and collects in the hepatic veins which empty into the IVC at the level of T10
Describe portal hypertension
Scar tissue in liver (cirrhosis) compresses blood vessels and reduces blood flow
Results in increased blood pressure in portal system
Blood flow is diverted to other veins and can cause ascites
The IVC returns blood from which 6 veins?
Hepatic
Lumbar
Gonadal
Renal
Adrenal
Phrenic
What are villi covered with?
simple columnar epithelium and microvilli
What is the purpose of the lamina propria with the villi?
The lamina propria of each villus contains an extensive network of capillaries which carry nutrients to the hepatic portal circulation for delivery to the liver
What is contained in each villi and what are they?
Lacteals: prominent lymphatic capillaries in the small intestine which function in the transport of lipids absorbed by the GI tract
What are Chylomicrons?
Protein-lipid packages that are too large to diffuse into the bloodstream
-give lipids “milky” appearance
Do chylomicrons go through the liver?
No, reach the venous circulation via the thoracic duct which drains into the left subclavian vein
Where do lymphatic capillaries drain?
Superficial lymphatics: located in subcutaneous layer deep to the skin and in connective tissue
Deep lymphatics: Larger lymphatic vessels that accompany deep arteries and veins supplying skeletal muscles, organs of the neck, limbs, and trunk, and walls of visceral organs
Where does lymph go from the superficial/deep lymphatics?
converge to form lymphatic trunks which empty into either the thoracic duct or the right lymphatic duct
-thoracic duct: 75%
-right lymphatic duct: 25%
Where is the thoracic duct located?
begins inferior to diaphragm at L2 and anterior to vertebral column
Passes posterior to diaphragm alongside the aorta
Ascends along the left side of the vertebral column to the level of the clavicle
Empties into the left subclavian vein
Where does the thoracic duct collect lymph from?
Left bronchomediastinal trunk
Left subclavian trunk
Left jugular trunk
What is the cisterna chyli
In the thoracic duct
-expanded, sac-like chamber at the base of the thoracic duct
-collects lymph from the inferior abdomen, pelvis, and lower limbs
Where does the right lymphatic duct collect lymph from?
right jugular trunk
right subclavian trunk
right bronchomediastinal trunk
What is lymphedema?
Blockage of lymphatic drainage from a limb, resulting in the accumulation of interstitial fluids in the limn
-stagnant fluids = higher infection rate
-if chronic, elastic tissue in the limb will lose its elasticity and the swelling will become permanent
