Key vocab
The term describes the total concentration of dissolved solutes in a solution.
What is osmolarity?
This type of environment has a higher solute concentration than an organism’s body fluids.
What is a hypertonic environment?
This structure is the functional unit of the kidney responsible for filtering blood and forming urine.
What is the nephron?
This process moves plasma from blood into the nephron.
What is filtration?
This hormone is released from the posterior pituitary and regulates water reabsorption in the kidney.
What is antidiuretic hormone (ADH)?
This biological concept refers to maintaining stable internal conditions despite environmental changes.
What is homeostasis?
In a hypertonic environment, water tends to move in this direction relative to the organism.
What is out of the organism?
This structure performs the initial filtration of blood in the nephron.
What is the glomerulus?
This process moves substances from the nephron back into the bloodstream.
What is reabsorption?
ADH primarily acts on this nephron structure.
What is the collecting duct?
Animals that maintain constant internal osmolarity even when the environment changes are called this.
What are osmoregulators?
This type of environment has a lower solute concentration than an organism’s body fluids.
What is a hypotonic environment?
This nephron structure reabsorbs a large portion of glucose, salts, and water.
What is the proximal convoluted tubule (PCT)?
This process moves substances from blood into the nephron to be eliminated.
What is secretion?
ADH increases this kidney process by inserting water channels into tubule membranes.
What is water reabsorption?
Animals that allow their internal osmolarity to match the surrounding environment are called this.
What are osmoconformers?
In a hypotonic environment, water tends to move in this direction relative to the organism.
What is into the organism?
This part of the Loop of Henle is permeable to water.
What is the descending limb of the Loop of Henle?
These specialized blood vessels run alongside the Loop of Henle and help maintain concentration gradients.
What are the vasa recta?
When ADH levels are high, urine becomes this.
What is more concentrated?
This type of membrane transport is required by osmoregulators to move salts against concentration gradients.
What is active transport?
Freshwater fish maintain osmotic balance by producing this type of urine.
What is large amounts of dilute urine?
This part of the Loop of Henle primarily transports salt out of the tubule.
What is the ascending limb of the Loop of Henle?
This mechanism helps maintain the kidney’s osmotic gradient to concentrate urine.
What is countercurrent exchange?
ADH has this effect on urine volume.
What is decreasing urine volume?