Question 1

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

Accepted Answer

A) hydrogen ions are actively moved into the filtrate. 
B) the sodium transporter exchanges one hydrogen ion for each sodium ion. 
C) excreted plasma proteins are nearly all acidic ions. 
D) excreted amino acids are in abundance. 
E) potassium and sodium exchange generates lots of acidity. 
A) hydrogen ions are actively moved into the filtrate. 
B) the sodium transporter exchanges one hydrogen ion for each sodium ion. 
C) excreted plasma proteins are nearly all acidic ions. 
D) excreted amino acids are in abundance. 
E) potassium and sodium exchange generates lots of acidity.

Question 2

African lungfish,which are often found in small stagnant pools of fresh water,produce urea as a nitrogenous waste.What is the advantage of this adaptation?

Accepted Answer

A) Urea takes less energy to synthesize than ammonia. 
B) Small stagnant pools do not provide enough water to dilute the toxic ammonia. 
C) The highly toxic urea makes the pool uninhabitable to potential competitors. 
D) Urea forms an insoluble precipitate. 
E) Urea makes lungfish tissue hypoosmotic to the pool. 
A) Urea takes less energy to synthesize than ammonia. 
B) Small stagnant pools do not provide enough water to dilute the toxic ammonia. 
C) The highly toxic urea makes the pool uninhabitable to potential competitors. 
D) Urea forms an insoluble precipitate. 
E) Urea makes lungfish tissue hypoosmotic to the pool.

Question 3

When stimulated by aldosterone,the reabsorption of Na⁺ is increased along

Accepted Answer

A) the loop of Henle. 
B) the collecting duct. 
C) Bowman's capsule. 
D) the proximal tubule. 
E) the distal tubule. 
A) the loop of Henle. 
B) the collecting duct. 
C) Bowman's capsule. 
D) the proximal tubule. 
E) the distal tubule.

Question 4

Use the following structural formulas to identify the following items.
  
-Which of the following is synthesized by mammals,most amphibians,sharks,and some bony fishes,and has lower toxicity than its nitrogenous substrate?

Accepted Answer

A) A 
B) B 
C) C 
D) D 
E) E 
A) A 
B) B 
C) C 
D) D 
E) E

Question 5

A person with alkalosis will likely excrete urine that has abnormally high levels of

Accepted Answer

A) bicarbonate ions. 
B) sodium ions. 
C) glucose. 
D) ammonia. 
E) NaOH. 
A) bicarbonate ions. 
B) sodium ions. 
C) glucose. 
D) ammonia. 
E) NaOH.

Question 6

What is the function of the osmotic gradient found in the kidney?

Accepted Answer

A) to allow electrolytes to move from low to high concentrations in the absence of ATP 
B) to permit the precise control of the retention of water and electrolytes 
C) to allow the loop of Henle to deliver water to the renal vein 
D) to control the filtration of large cells at the glomerulus 
E) to permit the excretion of damaged red blood cells 
A) to allow electrolytes to move from low to high concentrations in the absence of ATP 
B) to permit the precise control of the retention of water and electrolytes 
C) to allow the loop of Henle to deliver water to the renal vein 
D) to control the filtration of large cells at the glomerulus 
E) to permit the excretion of damaged red blood cells

Question 7

The typical osmolarity of human blood is

Accepted Answer

A) 30 mOsm/L. 
B) 100 mOsm/L. 
C) 200 mOsm/L. 
D) 300 mOsm/L. 
E) 500 mOsm/L. 
A) 30 mOsm/L. 
B) 100 mOsm/L. 
C) 200 mOsm/L. 
D) 300 mOsm/L. 
E) 500 mOsm/L.

Question 8

Organisms categorized as osmoconformers are most likely

Accepted Answer

A) found in freshwater lakes and streams. 
B) marine. 
C) amphibious. 
D) found in arid terrestrial environments. 
E) found in terrestrial environments with adequate moisture. 
A) found in freshwater lakes and streams. 
B) marine. 
C) amphibious. 
D) found in arid terrestrial environments. 
E) found in terrestrial environments with adequate moisture.

Question 9

The osmoregulatory/excretory system of an insect is based on the operation of

Accepted Answer

A) protonephridia. 
B) metanephridia. 
C) Malpighian tubules. 
D) nephrons. 
E) ananephredia. 
A) protonephridia. 
B) metanephridia. 
C) Malpighian tubules. 
D) nephrons. 
E) ananephredia.

Question 10

A primary reason that the kidneys have one of the highest metabolic rates of all body organs is that

Accepted Answer

A) it stores the body's excess fats. 
B) it has membranes of varying permeability to water. 
C) it operates an extensive set of active-transport ion pumps. 
D) it is the body's only means of shedding excess nutrients. 
E) it has an abundance of myogenic smooth muscle. 
A) it stores the body's excess fats. 
B) it has membranes of varying permeability to water. 
C) it operates an extensive set of active-transport ion pumps. 
D) it is the body's only means of shedding excess nutrients. 
E) it has an abundance of myogenic smooth muscle.

Question 11

Single-celled Paramecium live in pond water (a hypotonic environment).They have a structural feature,a contractile vacuole,which enables them to osmoregulate.If you observed them in the following solutions,at which sucrose concentration (in millimolars,mM)would you expect the contractile vacuole to be most active?

Accepted Answer

A) 0)0 mM sucrose 
B) 0)05 mM saline 
C) 0)08 mM sucrose 
D) 1)0 mM sucrose 
E) 1)0 mM saline 
A) 0)0 mM sucrose 
B) 0)05 mM saline 
C) 0)08 mM sucrose 
D) 1)0 mM sucrose 
E) 1)0 mM saline

Question 12

What must freshwater fish do to maintain homeostasis?

Accepted Answer

A) excrete large quantities of electrolytes 
B) consume large quantities of water 
C) excrete large quantities of water 
D) take in electrolytes through simple diffusion 
E) change the concentration of electrolytes in their blood 
A) excrete large quantities of electrolytes 
B) consume large quantities of water 
C) excrete large quantities of water 
D) take in electrolytes through simple diffusion 
E) change the concentration of electrolytes in their blood

Question 13

Which nitrogenous waste has the greatest number of nitrogen atoms?

Accepted Answer

A) ammonia 
B) ammonium ions 
C) urea 
D) uric acid 
A) ammonia 
B) ammonium ions 
C) urea 
D) uric acid

Question 14

Urea is

Accepted Answer

A) insoluble in water. 
B) more toxic to human cells than ammonia. 
C) the primary nitrogenous waste product of humans. 
D) the primary nitrogenous waste product of most birds. 
E) the primary nitrogenous waste product of most aquatic invertebrates. 
A) insoluble in water. 
B) more toxic to human cells than ammonia. 
C) the primary nitrogenous waste product of humans. 
D) the primary nitrogenous waste product of most birds. 
E) the primary nitrogenous waste product of most aquatic invertebrates.

Question 15

Unlike most bony fishes,sharks maintain body fluids that are isoosmotic to sea water,so they are considered by many to be osmoconformers.Nonetheless,these sharks osmoregulate at least partially by

Accepted Answer

A) using their gills and kidneys to rid themselves of sea salts. 
B) monitoring dehydration at the cellular level with special gated aquaporins. 
C) tolerating high urea concentrations that balance internal salt concentrations to seawater osmolarity. 
D) synthesizing trimethylamine oxide, a chemical that binds and precipitates salts inside cells. 
E) possessing a special adaptation that allows their cells to operate at an extraordinarily high salt concentration. 
A) using their gills and kidneys to rid themselves of sea salts. 
B) monitoring dehydration at the cellular level with special gated aquaporins. 
C) tolerating high urea concentrations that balance internal salt concentrations to seawater osmolarity. 
D) synthesizing trimethylamine oxide, a chemical that binds and precipitates salts inside cells. 
E) possessing a special adaptation that allows their cells to operate at an extraordinarily high salt concentration.

Question 16

The fluid with the highest osmolarity is

Accepted Answer

A) distilled water. 
B) plasma in birds. 
C) plasma in mammals. 
D) sea water in a tidal pool. 
E) estuarine water. 
A) distilled water. 
B) plasma in birds. 
C) plasma in mammals. 
D) sea water in a tidal pool. 
E) estuarine water.

Question 17

The necropsy (postmortem analysis)of a freshwater fish that died after being placed accidentally in salt water would likely show that

Accepted Answer

A) loss of water by osmosis from cells in vital organs resulted in cell death and organ failure. 
B) high amounts of salt had diffused into the fish's cells, causing them to swell and lyse. 
C) the kidneys were not able to keep up with the water removal necessary in this hyperosmotic environment, creating an irrevocable loss of homeostasis. 
D) the gills became encrusted with salt, resulting in inadequate gas exchange and a resulting asphyxiation. 
E) brain cells lysed as a result of increased osmotic pressure in this hyperosmotic environment, leading to death by loss of autonomic function. 
A) loss of water by osmosis from cells in vital organs resulted in cell death and organ failure. 
B) high amounts of salt had diffused into the fish's cells, causing them to swell and lyse. 
C) the kidneys were not able to keep up with the water removal necessary in this hyperosmotic environment, creating an irrevocable loss of homeostasis. 
D) the gills became encrusted with salt, resulting in inadequate gas exchange and a resulting asphyxiation. 
E) brain cells lysed as a result of increased osmotic pressure in this hyperosmotic environment, leading to death by loss of autonomic function.

Question 18

Increased ADH secretion is likely after

Accepted Answer

A) drinking lots of pure water. 
B) sweating-induced dehydration increases plasma osmolarity. 
C) ingestion of ethanol (drinking alcoholic drinks). 
D) eating a small sugary snack. 
E) blood pressure is abnormally high. 
A) drinking lots of pure water. 
B) sweating-induced dehydration increases plasma osmolarity. 
C) ingestion of ethanol (drinking alcoholic drinks). 
D) eating a small sugary snack. 
E) blood pressure is abnormally high.

Question 19

After drinking alcoholic beverages,increased urine excretion is the result of

Accepted Answer

A) increased aldosterone production. 
B) increased blood pressure. 
C) inhibited secretion of antidiuretic hormone (ADH). 
D) increased reabsorption of water in the proximal tubule. 
E) the osmoregulator cells of the brain increasing their activity. 
A) increased aldosterone production. 
B) increased blood pressure. 
C) inhibited secretion of antidiuretic hormone (ADH). 
D) increased reabsorption of water in the proximal tubule. 
E) the osmoregulator cells of the brain increasing their activity.

Question 20

A human who has no access to fresh water but is forced to drink sea water instead

Accepted Answer

A) will thrive under such conditions, as long as he has lived at the ocean most of his life. 
B) will excrete more water molecules than taken in, because of the high load of ion ingestion. 
C) will develop structural changes in the kidneys to accommodate the salt overload. 
D) will find that drinking saltwater satiates his thirst. 
E) will risk becoming overhydrated within 12 hours. 
A) will thrive under such conditions, as long as he has lived at the ocean most of his life. 
B) will excrete more water molecules than taken in, because of the high load of ion ingestion. 
C) will develop structural changes in the kidneys to accommodate the salt overload. 
D) will find that drinking saltwater satiates his thirst. 
E) will risk becoming overhydrated within 12 hours.

Exam 44: Osmoregulation and Excretion

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

African lungfish,which are often found in small stagnant pools of fresh water,produce urea as a nitrogenous waste.What is the advantage of this adaptation?

When stimulated by aldosterone,the reabsorption of Na⁺ is increased along

Use the following structural formulas to identify the following items. -Which of the following is synthesized by mammals,most amphibians,sharks,and some bony fishes,and has lower toxicity than its nitrogenous substrate?

A person with alkalosis will likely excrete urine that has abnormally high levels of

What is the function of the osmotic gradient found in the kidney?

The typical osmolarity of human blood is

Organisms categorized as osmoconformers are most likely

The osmoregulatory/excretory system of an insect is based on the operation of

A primary reason that the kidneys have one of the highest metabolic rates of all body organs is that

What must freshwater fish do to maintain homeostasis?

Which nitrogenous waste has the greatest number of nitrogen atoms?

Urea is

Unlike most bony fishes,sharks maintain body fluids that are isoosmotic to sea water,so they are considered by many to be osmoconformers.Nonetheless,these sharks osmoregulate at least partially by

The fluid with the highest osmolarity is

The necropsy (postmortem analysis)of a freshwater fish that died after being placed accidentally in salt water would likely show that

Increased ADH secretion is likely after

After drinking alcoholic beverages,increased urine excretion is the result of

A human who has no access to fresh water but is forced to drink sea water instead

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

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