Chapter 44

The movement of substances out of the glomerulus and into Bowman’s capsule is referred to as _____.

filtration

The movement of substances from the blood into the proximal tubule is known as _____.

secretion

Which of these is reabsorbed from filtrate?

all of these

As filtrate moves down the loop of Henle, the surrounding interstitial fluid becomes _____ concentrated than the filtrate, so _____ leaves the filtrate.

more … water

The most abundant solute in urine is _____.

urea (and other nitrogenous wastes)

Glucose is removed from filtrate by _____.

active transportation

You just received a freshwater aquarium as a gift and decide to add more fish. When you get to the pet store, you find that the most beautiful fish are saltwater animals, but you decide to buy them anyway. What will happen when you put your expensive saltwater fish in your freshwater aquarium?

The cells of the fish will take up too much water, and the fish will die.

Terrestrial animals are _____.

osmoregulators that must obtain water from the environment

Freshwater fish excrete nitrogenous wastes as _____.

ammonia

Urine formed by a kidney collects in the _____ before being drained from the kidney by the _____ and transported to the _____.

renal pelvis … ureter …urinary bladder

The _____ are the major blood vessels transporting blood to the kidneys.

renal arteries

The outer part of the kidney is the _____.

cortex

Which of these is the functional unit of a kidney?

nephron

Under the influence of antidiuretic hormone (ADH), _____ is produced.

more concentrated urine

Antidiuretic hormone (ADH) makes the _____ permeable to water.

collecting duct

What is the driving force for the filtration of blood by the renal corpuscle?

Higher pressure in glomerular capillaries than in the surrounding Bowman’s capsule.

Which regions of the nephron function independently of hormonal control for the most part?

Renal corpuscle, proximal tubule, and loop of Henle.

In which region of the nephron is a steep osmotic gradient created?

Loop of Henle.

Which of the following statements best describes the actions of the hormone ADH on the nephron?

ADH causes the collecting duct to increase water reabsorption by the surrounding tissue under conditions of dehydration.

Which of the following represents the correct sequence of flow through the nephron?

Renal corpuscle > proximal tubule > loop of Henle > distal tubule > collecting duct

Organisms categorized as osmoconformers are most likely

marine.

The body fluids of an osmoconformer would be ________ with its ________ environment.

isoosmotic; saltwater

Compared to the seawater around them, most marine invertebrates are

isoosmotic.

Many marine and freshwater bony fish achieve osmoregulation via

gain of water through food.

Urea is produced in the

liver from NH3 and CO2.

Materials are returned to the blood from the filtrate by which of the following processes?

selective reabsorption

Excretory structures known as protonephridia are present in

flatworms

Excretory organs known as Malpighian tubules are present in

insects

The osmoregulatory process called secretion refers to the

selective elimination of excess ions and toxins from body fluids.

The transfer of fluid from the glomerulus to Bowman’s capsule

is mainly a consequence of blood pressure in the capillaries of the glomerulus.

Juxtamedullary nephrons can concentrate salt effectively in the renal medulla because of their long

loops of Henle.

Human urine is usually more acidic than most other body fluids because

hydrogen ions are actively moved into the filtrate.

Aldosterone is _____.

a steroid hormone that reduces the amount of fluid excreted in the urine

Increased ADH secretion is likely after

sweating-induced dehydration increases plasma osmolarity.

ADH and RAAS work together in maintaining osmoregulatory homeostasis through which of the following ways?

ADH regulates the osmolarity of the blood by altering renal reabsorption of water, and RAAS maintains the osmolarity of the blood by stimulating Na+ and water reabsorption.

Unlike an earthworm’s metanephridia, a mammalian nephron

receives filtrate from blood instead of coelomic fluid.

Select the correct statement about osmolarity.

If two solutions are separated by a selectively permeable membrane, water flows by osmosis from a hyperosmotic solution to a hypoosmotic one.
The contents of an animal cell are hyperosmotic.
Osmolarity measures the moles of solute per liter of solution.

Osmolarity measures the moles of solute per liter of solution.