Chatper 49 Excretory System Part 2 Flashcards
Collectively, the kidneys, ureters, urinary bladder, and urethra.
Urinary System
Depending on size of the kidney, there can be several million similar, single-cell-thick structures. This is the structure that creates filtrate, and filters.
Nephrons
Filtering process begins here. A filtrate from blood is formed that is free of cells and proteins. (A glomerulus and Bowman’s capsule.
Renal Corpuscle
A cluster of capilleries. Each is supplied by blood under pressure by afferent arteriole and efferent arteriole. The capilleries contain tiny holes for rapid flow of plasma out of capillaries.
Glomerulus
Brings blood to the glomerulus
Afferent Arteriole
Takes blood away from the glomerulus.
Efferent Arteriole
A fluid-filled space the bolmerulus resides in.
Bowman’s Capsule
The segment of the tubule that drains the Bowman’s capsule. (close to bowman’s)
Proximal Tubule
A long, hairpin-shaped loop consisting of a descending limb coming from the proximal tubule and an ascending limb. The filtrate is dumped into one of the collecting ducts in the kidney.
Loop of Henle
Capillaries that carry away reabsorbed solutes and water from the filtrate in the nephron and return them to the bloodstream.
Vasa recta capillaries
The Loop of Henle requires energy-dependent ion pumps to maintain the necessary concentration gradient. It reduces the final volume of urine produced and recaptures water along the osmotic gradient. (prevents dehydration)
Countercurrent multiplication system.
Blood from the patient’s arteries is purified by redirecting it through a dialysis machine.Filters like a kidney.
Hemodialysis
Salts and minerals that can conduct electrical impulses in the body. Common human electrolytes are sodium chloride, potassium, calcium, and sodium bicarbonate.
Electrolytes
What are the 3 forms of nitrogenous waste?
Ammonia—NH3
Urea
Uric Acid
What is the difference between osmoregulators and osmoconformers?
Osmoregulators control the amount of salt within their bodies.
Osmoconformers let the environment dictate the amount of salt within their bodies.
List and describe Filtration, Reabsorption, Secretion, and Excretion.
Filtration—ions and other substances are separated from blood and plasma. They are filtered out.
Reabsorption—takes parts of the filtrate that is still needed in the body and returns those parts to the body.
Secretion—Some organs send substances directly to the kidney to be put directly into the urine without being filtered.
Excretion—expelling waste from the body to the external environment.
Compare and contrast kidneys in Freshwater fish, Marine fish, and Desert mammals.
Fish barely have kidneys. Freshwater fish kidneys will work to remove excess water from the fish’s system and retain salt. Urine is hypoosmotic. Excretes ammonia.
Marine fish need water but filter out salt. Urine is hyperosmotic, Excretes ammonia.
Desert mammals water preservation is tantamount, urine is hyperosmotic, excretes urea. Drinks no water: very long loops of Henle; depends on water generated by cellular metabolism.
How do insects secret waste?
In the Mapighian tubules resides the secretory system of an insect. Epithelial cells transport salts and uric acid into the tubule lumen from the hemolymph. Water enters the lumen by osmosis. The fluid moves into the hindgut (intestine and rectum), where salts and water are reabsorbed into the hemolymph. Wastes are excreted with feces through the nus.
List and describe the vertebrate mechanism of osmoregulation.
Kidneys, Ureters, Urinary bladder, Urethra.
Nephron, Renal corpuscle, Glomerulus, Bowman’s capsule, Proximal tube, Loop of Henle.
