Organ Architecture II - Solid Organs Flashcards
What are the two types of exocrine glands?
Simple and Compound
Simple exocrine glands are _____ and _____.
Simple exocrine glands are TUBULAR and UNBRANCHED.
What are the functions of the proximal and distal parts of simple exocrine gland tubes.
Proximal: the proximal part of the tube is a duct, to carry the secreted material
Distal: the distal part of the tube is the secretory portion
What is unique about compound exocrine glands in contrast to the simple exocrine glands?
The ducts of compound exocrine glands branch off leading to many round acini.
They look like bundles of grapes (acini)!
Acini are the secretory parts of the gland.
What is the parenchyma of solid organs?
The part that does the main work of the organs. Invagination of epithelium.
Glands are part of the parenchyma.
What is the stroma of solid organs?
It is the supporting CT of the parenchyma. It includes the CT, blood vessels, and nerves.
The pancreas contains both endocrine and exocrine cells. What is the most common?
Most of the cells of the pancrease are exocrine and produce digestive enzyme precursors.
Pancreatic acini have clusters of ______ cells surrounding a central lumen.
secretory
The pancreas is a lobular organ, divided by _____ filled with _____________.
septa; connective tissue
Ducts of the pancreas are lined by what cells?
cuboidal cells
These ducts collect what?
Digestive enzyme precursors
These ducts join to form larger ducts which will eventually lead to the duodenum where the enzymes will be activated to aid in digestion
The endocrine portion of the pancreas are small “islands” of lighter-staining cells called what?
Islets of Langerhans
Islets of Langerhans secrete what several hormones, name two.
Insulin and Glucagon
these control glucose levels in the blood
Deoxygenated blood from the systemic circulatory system leaves the stomach, pancreas, and intestines, and travels to the liver via what vessel?
Hepatic Portal Vein
The hepatic portal vein (HPV) is responsible for what percentage of blood supply to the liver? What is responsible for the remainder of the blood supply?
HPV supplies 80%
Hepatic artery supplies the other 20%
The HPV and hepatic artery enter or leave from the liver? Where?
The HPV and hepatic artery enter the liver at the hilus.
This is also where the bile duct leaves the liver.
Both the HPV and hepatic artery branch into smaller peices and eventually spill into sinusoids (small capillary beds) that surround hepatocytes.
The blood in the liver drains through the sinusoids into what?
a central vein
central veins join to form short hepatic veins that join and empty to the inferior vena cava
Central veins join to form short hepatic veins that join and empty to the _____
inferior vena cava
Bile travels in the opposite or same direction as blood in the liver?
opposite
What creates bile?
hepatocytes
bile does not mix with blood
Bile in the liver is secreted from the endothelial/hepatocyte cells into what?
bile caniliculi
What are bile caniliculi?
small grooves between each hepatocyte
the caniliculi drain into larger ducts and eventually the bile duct
What are the three major parts of portal tracts in the liver?
hepatic portal veins, hepatic arteries, and bile duct
What are glomeruli (kidney)?
small tufts of blood vessels (capillaries) at which blood is under high pressure
there are fenestrations in the endothelium of the blood vessels and podocyte cells that form the epithelium of Bowman’s capuse, allowing materials that are small enough to pass through the holes for filtration
Where is the site of plasma filtration in the kidney?
Glomeruli
Kidney tubules make up most of the cells of the kidney. The tubules selectively reabsorb material that is in the filtrate. What type of epithelium do these kidney tubules have?
cuboidal epithelium
Where are the blood vessels of the kidney located?
in the glomeruli for plasma filtration
blood cells also run long the tubules to pick up filtrate that was reabsorbed
How much interstitium is visible in a healthy kidney?
very little
What are the main, basic functions of the digestive tract?
- to break down and absorb nutrients from food
- contains smooth muscle to move food through tract
- release of enzymes in order to break down food
- small itetstine has villi to increase surface area for absorption, while large intestine has no villi but has more goblet cells to create more mucus to move drier material through
What are the main, basic functions of the lung?
- to remove CO2 from the cells and deliver oxygen to them
- many alveoli with very thin septa separating air from capillaries; this allows gas exchange to occur easily
What are the main, basic functions of the airways?
- to transmit air to alveoli
- they have thicker epithelium, and in some cases cartilage to hold them open
- they branch many times in order to increase the surface area for gas exchange at the alveoli
What are the main, basic functions of the pancreas?
- to produce digestive enzymes and to produce hormones regulating glucose in the body
- digestive enzymes come from exocrine glands and are carried through ducts to the duodenum
- hormones, insulin and glucagon, are secreted from Islets of Langerhans and make their way into the blood where they can affect the storage and release of glucose, depending on the body’s needs
What are the main, basic functions of the liver?
- to process nutrients, remove toxins, secrete bile, and synthesize plasma proteins
- hepatocytes fill a circular bed around a central vein
- blood pours in around the edges from the portal veins and hepatic arteries, filters through sinusoids, and drains out of the central vein to hepatic veins and out of the liver
- ->this exposes the blood to many different cells which have the ability to perform all of the listed functions
What are the main, basic functions of the kidney?
- to filter the blood and remove waste
- the glomerulus is fenestrated to allow filtrate through the holes
- the tubules are long and dip deep into the medulla, allowing the body to recover needed ions from the filtrate while leaving waste untouched
- the tubules drain into collecting ducts, which eventually drain into the pelvis of the kidney into ureters and finally into the bladder for excretion
