Question 1

Ammonia is likely to be the primary nitrogenous waste in living conditions that include

Accepted Answer

A) lots of fresh water flowing across the gills of a fish. 
B) lots of sea water, such as a bird living in a marine environment. 
C) lots of sea water, such as a marine mammal (e.g., a polar bear). 
D) a terrestrial environment, such as that supporting crickets. 
E) a moist system of burrows, such as those of naked mole rats. 
A) lots of fresh water flowing across the gills of a fish. 
B) lots of sea water, such as a bird living in a marine environment. 
C) lots of sea water, such as a marine mammal (e.g., a polar bear). 
D) a terrestrial environment, such as that supporting crickets. 
E) a moist system of burrows, such as those of naked mole rats.

Question 2

Processing of filtrate in the proximal and distal tubules

Accepted Answer

A) achieves the sorting of plasma proteins according to size. 
B) achieves the conversion of toxic ammonia to less toxic urea. 
C) maintains homeostasis of pH in body fluids. 
D) regulates the speed of blood flow through the nephrons. 
E) reabsorbs urea to maintain osmotic balance. 
A) achieves the sorting of plasma proteins according to size. 
B) achieves the conversion of toxic ammonia to less toxic urea. 
C) maintains homeostasis of pH in body fluids. 
D) regulates the speed of blood flow through the nephrons. 
E) reabsorbs urea to maintain osmotic balance.

Question 3

In a laboratory experiment with three groups of students,one group drinks pure water,a second group drinks an equal amount of beer,and a third group drinks an equal amount of concentrated salt solution,all during the same time period.Their urine production is monitored for several hours.Which groups are expected to have the greatest and least amounts of urine,respectively?

Accepted Answer

A) Beer drinkers have the most; salt solution drinkers have the least. 
B) Salt solution drinkers have the most; water drinkers have the least. 
C) Water drinkers have the most; beer drinkers have the least. 
D) Beer drinkers have the most; water drinkers have the least. 
E) There will be no significant difference between these groups. 
A) Beer drinkers have the most; salt solution drinkers have the least. 
B) Salt solution drinkers have the most; water drinkers have the least. 
C) Water drinkers have the most; beer drinkers have the least. 
D) Beer drinkers have the most; water drinkers have the least. 
E) There will be no significant difference between these groups.

Question 4

Which of the following most accurately describes selective permeability?

Accepted Answer

A) An input of energy is required for transport. 
B) Lipid-soluble molecules pass through a membrane. 
C) There must be a concentration gradient for molecules to pass through a membrane. 
D) Only certain molecules can cross a cell membrane. 
E) Water-soluble molecules pass through a membrane. 
A) An input of energy is required for transport. 
B) Lipid-soluble molecules pass through a membrane. 
C) There must be a concentration gradient for molecules to pass through a membrane. 
D) Only certain molecules can cross a cell membrane. 
E) Water-soluble molecules pass through a membrane.

Question 5

In its native habitat,the sea lamprey (Petromyzon marinus)has a diadromous lifecycle.When preparing to migrate from fresh water to the sea,the lamprey must metamorphose so that it can survive the change in salinity.To achieve osmoregulation in the sea,the lamprey must

Accepted Answer

A) decrease water uptake and decrease solute excretion. 
B) increase water uptake and increase solute excretion. 
C) decrease water uptake and increase solute excretion. 
D) increase water uptake and decrease solute excretion. 
E) decrease water uptake and decrease solute absorption. 
A) decrease water uptake and decrease solute excretion. 
B) increase water uptake and increase solute excretion. 
C) decrease water uptake and increase solute excretion. 
D) increase water uptake and decrease solute excretion. 
E) decrease water uptake and decrease solute absorption.

Question 6

The osmoregulatory process called secretion refers to the

Accepted Answer

A) formation of filtrate at an excretory structure. 
B) reabsorption of nutrients from a filtrate. 
C) selective elimination of excess ions and toxins from body fluids. 
D) formation of an osmotic gradient along an excretory structure. 
E) expulsion of urine from the body. 
A) formation of filtrate at an excretory structure. 
B) reabsorption of nutrients from a filtrate. 
C) selective elimination of excess ions and toxins from body fluids. 
D) formation of an osmotic gradient along an excretory structure. 
E) expulsion of urine from the body.

Question 7

Use the following information to answer the next few questions.
While spelunking,you have discovered a new species deep inside the cave.This animal does not have easy access to water.It has a dense coat of fur,a four-chambered heart,and a closed circulatory system.
-You expect the animal's urine to be

Accepted Answer

A) isoosmotic to body fluids. 
B) hypoosmotic to body fluids. 
C) hypotonic to body fluids. 
D) hyperosmotic to body fluids. 
E) isotonic to body fluids. 
A) isoosmotic to body fluids. 
B) hypoosmotic to body fluids. 
C) hypotonic to body fluids. 
D) hyperosmotic to body fluids. 
E) isotonic to body fluids.

Question 8

Birds secrete uric acid as their nitrogenous waste because uric acid

Accepted Answer

A) is readily soluble in water. 
B) is metabolically less expensive to synthesize than other excretory products. 
C) requires little water for nitrogenous waste disposal, thus reducing body mass. 
D) excretion allows birds to live in desert environments. 
E) costs less to produce than other excretory products 
A) is readily soluble in water. 
B) is metabolically less expensive to synthesize than other excretory products. 
C) requires little water for nitrogenous waste disposal, thus reducing body mass. 
D) excretion allows birds to live in desert environments. 
E) costs less to produce than other excretory products

Question 9

Antidiuretic hormone (ADH)functions at the cellular level by

Accepted Answer

A) stimulating the reabsorption of glucose through channel proteins. 
B) triggering the synthesis of an enzyme that makes the phospholipid bilayer more permeable to water. 
C) causing membranes to include more phospholipids that have unsaturated fatty acids. 
D) causing an increase in the number of aquaporin molecules of collecting duct cells. 
E) decreasing the speed at which filtrate flows through the nephron, leading to increased reabsorption of water. 
A) stimulating the reabsorption of glucose through channel proteins. 
B) triggering the synthesis of an enzyme that makes the phospholipid bilayer more permeable to water. 
C) causing membranes to include more phospholipids that have unsaturated fatty acids. 
D) causing an increase in the number of aquaporin molecules of collecting duct cells. 
E) decreasing the speed at which filtrate flows through the nephron, leading to increased reabsorption of water.

Question 10

Use the following information to answer the next few questions.
After a long week,you join a few friends at a local pub to enjoy a meal and have a few beers.After a few hours and several beers,you find yourself to be quite thirsty.
-You feel thirsty because

Accepted Answer

A) you ate very salty pub food. 
B) you abstained from alcohol and drank water. 
C) you drank a few beers. 
D) you ate salty pub food and drank a few beers. 
E) you drank water and ate salty pub food. 
A) you ate very salty pub food. 
B) you abstained from alcohol and drank water. 
C) you drank a few beers. 
D) you ate salty pub food and drank a few beers. 
E) you drank water and ate salty pub food.

Question 11

Use the following information to answer the next few questions.
After a long week,you join a few friends at a local pub to enjoy a meal and have a few beers.After a few hours and several beers,you find yourself to be quite thirsty.
-Unlike an earthworm's metanephridia,a mammalian nephron

Accepted Answer

A) is intimately associated with a capillary network. 
B) forms urine by changing fluid composition inside a tubule. 
C) functions in both osmoregulation and excretion. 
D) receives filtrate from blood instead of coelomic fluid. 
E) has a transport epithelium. 
A) is intimately associated with a capillary network. 
B) forms urine by changing fluid composition inside a tubule. 
C) functions in both osmoregulation and excretion. 
D) receives filtrate from blood instead of coelomic fluid. 
E) has a transport epithelium.

Question 12

Birds that live in marine environments and thus lack access to fresh drinking water

Accepted Answer

A) osmoregulate without using a transport epithelium for this purpose. 
B) drink sea water and secrete excess ions through their kidneys only. 
C) drink sea water and secrete excess ions mainly through their nasal salt glands. 
D) have plasma that is isoosmotic to ocean water. 
E) obtain water by eating only osmoregulating prey. 
A) osmoregulate without using a transport epithelium for this purpose. 
B) drink sea water and secrete excess ions through their kidneys only. 
C) drink sea water and secrete excess ions mainly through their nasal salt glands. 
D) have plasma that is isoosmotic to ocean water. 
E) obtain water by eating only osmoregulating prey.

Question 13

After mistakenly adding salt to your freshwater tank,all of your fish died because

Accepted Answer

A) they were isosmotic to the saltwater. 
B) they are a stenohaline species. 
C) they are a diadromous species. 
D) they are a euryhaline species. 
E) they were hyperosmotic to the saltwater. 
A) they were isosmotic to the saltwater. 
B) they are a stenohaline species. 
C) they are a diadromous species. 
D) they are a euryhaline species. 
E) they were hyperosmotic to the saltwater.

Question 14

Many marine and freshwater bony fish achieve osmoregulation via

Accepted Answer

A) loss of water through the gills. 
B) gain of salt through the gills. 
C) loss of water in the urine. 
D) no drinking of water. 
E) gain of water through food. 
A) loss of water through the gills. 
B) gain of salt through the gills. 
C) loss of water in the urine. 
D) no drinking of water. 
E) gain of water through food.

Question 15

The advantage of excreting nitrogenous wastes as urea rather than as ammonia is that

Accepted Answer

A) urea can be exchanged for Na⁺. 
B) urea is less toxic than ammonia. 
C) urea requires more water for excretion than ammonia. 
D) urea does not affect the osmolar gradient. 
E) less nitrogen is removed from the body. 
A) urea can be exchanged for Na⁺. 
B) urea is less toxic than ammonia. 
C) urea requires more water for excretion than ammonia. 
D) urea does not affect the osmolar gradient. 
E) less nitrogen is removed from the body.

Question 16

Low selectivity of solute movement in the nephron is a characteristic of

Accepted Answer

A) salt pumping to control osmolarity. 
B) H⁺ pumping to control pH. 
C) reabsorption mechanisms along the proximal tubule. 
D) filtration from the glomerular capillaries. 
E) secretion along the distal tubule. 
A) salt pumping to control osmolarity. 
B) H⁺ pumping to control pH. 
C) reabsorption mechanisms along the proximal tubule. 
D) filtration from the glomerular capillaries. 
E) secretion along the distal tubule.

Question 17

Excretory organs known as Malpighian tubules are present in

Accepted Answer

A) earthworms. 
B) flatworms. 
C) insects. 
D) jellyfish. 
E) sea stars. 
A) earthworms. 
B) flatworms. 
C) insects. 
D) jellyfish. 
E) sea stars.

Question 18

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

Accepted Answer

A) ADH regulates the osmolarity of the blood and RAAS regulates the volume of the blood. 
B) ADH regulates the osmolarity of the blood by altering renal reabsorption of water, and RAAS maintains the osmolarity of the blood by stimulating Na⁺ reabsorption. 
C) ADH and RAAS work antagonistically; ADH stimulates water reabsorption during dehydration and RAAS causes increased excretion of water when it is in excess in body fluids. 
D) Both stimulate the adrenal gland to secrete aldosterone, which increases both blood volume and pressure via its receptors in the urinary bladder. 
E) ADH and RAAS combine at the receptor sites of proximal tubule cells, where reabsorption of essential nutrients takes place. 
A) ADH regulates the osmolarity of the blood and RAAS regulates the volume of the blood. 
B) ADH regulates the osmolarity of the blood by altering renal reabsorption of water, and RAAS maintains the osmolarity of the blood by stimulating Na⁺ reabsorption. 
C) ADH and RAAS work antagonistically; ADH stimulates water reabsorption during dehydration and RAAS causes increased excretion of water when it is in excess in body fluids. 
D) Both stimulate the adrenal gland to secrete aldosterone, which increases both blood volume and pressure via its receptors in the urinary bladder. 
E) ADH and RAAS combine at the receptor sites of proximal tubule cells, where reabsorption of essential nutrients takes place.

Question 19

Urea is produced in the

Accepted Answer

A) liver from NH₃ and CO₂. 
B) liver from glycogen. 
C) kidneys from glucose. 
D) kidneys from glycerol and fatty acids. 
E) bladder from uric acid and H₂O. 
A) liver from NH₃ and CO₂. 
B) liver from glycogen. 
C) kidneys from glucose. 
D) kidneys from glycerol and fatty acids. 
E) bladder from uric acid and H₂O.

Question 20

Tissues of sharks are isotonic to seawater,but their concentrations of sodium ions,potassium ions,and chloride ions in cells and extracellular fluids are similar to those of freshwater fishes.What can you infer about the movement of sodium and chloride in these animals?

Accepted Answer

A) To maintain homeostasis of sodium and chloride levels, the shark must take up additional sodium and chloride from seawater. 
B) Sodium and chloride will diffuse into shark gills from seawater down their concentration gradient. 
C) Sharks conserve sodium and chloride, limiting excretion. 
D) Sodium and chloride must be eliminated through the gills. 
E) Sodium and chloride will diffuse from the sharks gills into seawater down their concentration gradient. 
A) To maintain homeostasis of sodium and chloride levels, the shark must take up additional sodium and chloride from seawater. 
B) Sodium and chloride will diffuse into shark gills from seawater down their concentration gradient. 
C) Sharks conserve sodium and chloride, limiting excretion. 
D) Sodium and chloride must be eliminated through the gills. 
E) Sodium and chloride will diffuse from the sharks gills into seawater down their concentration gradient.

Exam 44: Osmoregulation and Excretion

Ammonia is likely to be the primary nitrogenous waste in living conditions that include

Processing of filtrate in the proximal and distal tubules

Which of the following most accurately describes selective permeability?

In its native habitat,the sea lamprey (Petromyzon marinus)has a diadromous lifecycle.When preparing to migrate from fresh water to the sea,the lamprey must metamorphose so that it can survive the change in salinity.To achieve osmoregulation in the sea,the lamprey must

The osmoregulatory process called secretion refers to the

Birds secrete uric acid as their nitrogenous waste because uric acid

Antidiuretic hormone (ADH)functions at the cellular level by

Use the following information to answer the next few questions. After a long week,you join a few friends at a local pub to enjoy a meal and have a few beers.After a few hours and several beers,you find yourself to be quite thirsty. -You feel thirsty because

Use the following information to answer the next few questions. After a long week,you join a few friends at a local pub to enjoy a meal and have a few beers.After a few hours and several beers,you find yourself to be quite thirsty. -Unlike an earthworm's metanephridia,a mammalian nephron

Birds that live in marine environments and thus lack access to fresh drinking water

After mistakenly adding salt to your freshwater tank,all of your fish died because

Many marine and freshwater bony fish achieve osmoregulation via

The advantage of excreting nitrogenous wastes as urea rather than as ammonia is that

Low selectivity of solute movement in the nephron is a characteristic of

Excretory organs known as Malpighian tubules are present in

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

Urea is produced in the

Tissues of sharks are isotonic to seawater,but their concentrations of sodium ions,potassium ions,and chloride ions in cells and extracellular fluids are similar to those of freshwater fishes.What can you infer about the movement of sodium and chloride in these animals?

Introduction: Evolution and Themes of Biology

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

From Gene to Protein

Regulation of Gene Expression

Viruses

DNA Tools and Biotechnology

Genomes and Their Evolution

Descent with Modification: A Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity II: The Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Plant Structure,Growth,and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons,Synapses,and Signalling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behaviour

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

Filters