1. © 2015 Pearson Education, Inc.

2. Osmoregulation and Excretion
Figure
Chapter 25
Figure Chapter 25: Big Ideas
Osmoregulation and Excretion
Thermoregulation

3. Thermoregulation
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4. Evaporation Radiation Convection Conduction Figure 25.1
Figure 25.1 Mechanisms of heat exchange

6. Figure 25.2a Heat dissipation via radiation (blood vessel dilation) and convection (ear flapping)

8. Blood returning to body core in vein
Figure 25.2b
Blood returning to body core in vein
Blood from body core in artery
35
33C
Figure 25.2b Countercurrent heat exchange
30
27
20
18
10 9

9. Figure
Figure How do emperor penguins maintain their warmth during the Antarctic winter? (photo: emperor penguins)

10. Figure 25.UN06
Figure 25.UN06 Testing your knowledge, question 21

11. Hypodermis (under the skin)
Figure 20.12
Hair
Epidermis
Sweat pore
Muscle
Dermis
Nerve
Sweat gland
Figure A section of skin, the major organ of the integumentary system
Hypodermis (under the skin)
Adipose tissue
Blood vessels
Oil gland
Hair follicle

12. Ruptured, inflammed pore
Figure 20.12a
Hair
Skin surface
Pus
White blood cells
Ruptured, inflammed pore
Bacteria (P. acnes)
Figure 20.12a The anatomy of a pimple
Oil gland
Hair follicle (pore)

13. Glands secrete sweat that evaporates, cooling the body
Figure
Glands secrete sweat that evaporates, cooling the body
The hypothalamus activates cooling mechanisms
Blood vessels in the skin dilate, increasing heat loss
Temperature decreases
The hypothalamus shuts off the cooling mechanisms
Temperature rises above set point
Homeostasis: Body temperature approximately 37C
Temperature increases
The hypothalamus shuts off the warming mechanisms
Temperature falls below set point
Figure Feedback control of body temperature
Blood vessels in the skin constrict, minimizing heat loss
The hypothalamus activates warming mechanisms
Skeletal muscles contract; shivering generates heat

14. Osmoregulation and Excretion
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15. Osmoregulation and Excretion
Figure
Chapter 25
Figure Chapter 25: Big Ideas
Osmoregulation and Excretion
Thermoregulation

16. Evaporation, urinary system
Figure 25.UN02
Gain Water
Lose Water
Salt
Freshwater Fish
Osmosis
Excretion
Pump in
Saltwater Fish
Drinking
Osmosis
Excrete, pump out
Land Animal
Drinking, eating
Evaporation, urinary system
Figure 25.UN02 Reviewing the concepts, 25.4

17. Gain of water and salt ions from food
Figure
Marine fish
Gain of water and salt ions from food
Excretion of salt ions from gills
Osmotic water loss through gills and other parts of body surface
SEAWATER
Figure Osmoregulation in a marine fish (part 1)
Excretion of salt ions and small amounts of water in concentrated urine from kidneys
Key
Gain of water and salt ions from drinking seawater
Water
Salt

18. Gain of water and some ions in food Uptake of salt ions by gills
Figure
Freshwater fish
Gain of water and some ions in food
Uptake of salt ions by gills
Osmotic water gain through gills and other parts of body surface
FRESH WATER
Figure Osmoregulation in a freshwater fish (part 2)
Excretion of salt ions and large amounts of water in dilute urine from kidneys
Key
Water
Salt

19. Figure
Marine fish
Freshwater fish
Gain of water and salt ions from food
Excretion of salt ions from gills
Osmotic water loss through gills and other parts of body surface
Gain of water and some ions in food
Uptake of salt ions by gills
Osmotic water gain through gills and other parts of body surface
SEAWATER
FRESH WATER
Gain of water and salt ions from drinking seawater
Excretion of salt ions and small amounts of water in concentrated urine from kidneys
Excretion of salt ions and large amounts of water in dilute urine from kidneys
Figure Osmoregulation in marine and freshwater fish: a comparison
Key
Water
Salt

20. Breakdown of nitrogen- containing macromolecules
Figure 25.5
Proteins
Nucleic acids
Breakdown of nitrogen- containing macromolecules
Amino acids
Nitrogenous bases
Removal of nitrogen- containing amino group
—NH2 (amino groups)
Conversion to nitrogenous waste
Ammonia
Urea
Uric acid
Figure 25.5 Nitrogen-containing metabolic waste products
Most aquatic animals, including most bony fishes
Mammals, most amphibians, sharks, some bony fishes
Birds and many other reptiles, insects, land snails

21. Renal artery (red) and vein (blue)
Figure 25.6a-1
Aorta
Inferior vena cava
Renal artery (red) and vein (blue)
Kidney
Ureter
Urinary bladder
Figure 25.6a-1 Anatomy of the human urinary system: the urinary system (part 1)
Urethra
The urinary system

22. Renal cortex Renal medulla Renal artery Renal vein Renal pelvis Ureter
Figure 25.6a-2
Renal cortex
Renal medulla
Renal artery
Renal vein
Renal pelvis
Figure 25.6a-2 Anatomy of the human urinary system: the kidney (part 2)
Ureter
The kidney

23. Orientation of a nephron and its collecting duct within the kidney
Figure 25.6a-3
Tubule
Renal cortex
Bowman’s capsule
Branch of renal artery
Collecting duct
Branch of renal vein
Renal medulla
To renal pelvis
Figure 25.6a-3 Anatomy of the human urinary system: nephron orientation (part 3)
Orientation of a nephron and its collecting duct within the kidney

24. Orientation of a nephron and its collecting duct within the kidney
Figure 25.6a-0
Renal cortex
Aorta
Tubule
Renal medulla
Inferior vena cava
Renal cortex
Bowman’s capsule
Renal artery
Renal artery (red) and vein (blue)
Branch of renal artery
Collecting duct
Renal vein
Kidney
Branch of renal vein
Renal pelvis
Ureter
Renal medulla
To renal pelvis
Urinary bladder
Ureter
Urethra
The urinary system
Figure 25.6a-0 Anatomy of the human urinary system
The kidney
Orientation of a nephron and its collecting duct within the kidney

25. Animation: Nephron Introduction
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26. Arteriole from renal artery
Figure 25.6b
Bowman’s capsule 1
Proximal tubule
Glomerulus
Capillaries
Arteriole from renal artery 3
Distal tubule
Arteriole exiting glomerulus
Collecting duct
Branch of renal vein
From another nephron
Figure 25.6b Detailed structure of a nephron 2
Loop of Henle with capillary network

27. Reabsorption (Removal from filtrate) Secretion (Addition to filtrate)
Figure 25.6c-0
Key
Filtration
Reabsorption
Secretion
Excretion
Bowman’s
capsule
From renal artery
Filtration
Reabsorption (Removal from filtrate)
Secretion (Addition to filtrate)
Excretion
Nephron tubule
Filtrate
H2O, other small molecules
Urine
Interstitial fluid
Figure 25.6c-0 Major processes of the urinary system
To renal vein
Capillary

28. H2O, other small molecules
Figure 25.6c-1
Key
Filtration
Reabsorption
Secretion
Excretion
Bowman’s
capsule
From renal artery
Filtration
Nephron tubule
Filtrate
H2O, other small molecules
Figure 25.6c-1 Major processes of the urinary system (part 1)
Interstitial fluid
Capillary

29. Reabsorption (Removal from filtrate) Secretion (Addition to filtrate)
Figure 25.6c-2
Key
Filtration
Reabsorption
Secretion
Excretion
Reabsorption (Removal from filtrate)
Secretion (Addition to filtrate)
Excretion
Nephron tubule
Urine
Figure 25.6c-2 Major processes of the urinary system (part 2)
To renal vein
Capillary

30. Animation: Bowman’s Capsule and Proximal Tubule
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31. Animation: Loop of Henle and Distal Tubule
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32. Animation: Collecting Duct
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33. Animation: Effect of ADH
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34. Initial filtrate composition Salts (NaCl and others) H2O H+
Figure
Bowman’s capsule
Proximal tubule
Nutrients
H2O
NaCl
HCO3−
Blood 1 1 H+
Some drugs and poisons
Initial filtrate composition
Salts (NaCl and others)
H2O H+
HCO3− (bicarbonate)
Urea
Nutrients
(glucose, amino acids)
Some drugs
Cortex
Medulla
Loop of Henle
Interstitial fluid 2
H2O
Figure Reabsorption and secretion in a nephron and its collecting duct (part 1)
Key
Reabsorption
Secretion
Filtrate movement

35. Urine (to renal pelvis)
Figure
Distal tubule
H2O
NaCl
HCO3− 4 K+ H+
Collecting duct 5
NaCl
NaCl 3
Urea
Figure Reabsorption and secretion in a nephron and its collecting duct (part 2)
NaCl
H2O
Key
Reabsorption
Secretion
Filtrate movement
Urine (to renal pelvis)

36. Initial filtrate composition Salts (NaCl and others) H2O H+
Figure
Bowman’s capsule
Proximal tubule
Distal tubule
Nutrients
H2O
H2O
NaCl
HCO3−
NaCl
HCO3−
Blood 4 1 1 H+ K+ H+
Some drugs and poisons
Collecting duct
Initial filtrate composition
Salts (NaCl and others)
H2O H+
HCO3− (bicarbonate)
Urea
Nutrients
(glucose, amino acids)
Some drugs
Cortex
Medulla
Loop of Henle 5
NaCl
Interstitial fluid 2
NaCl 3
H2O
Urea
Figure Reabsorption and secretion in a nephron and its collecting duct
NaCl
H2O
Key
Reabsorption
Secretion
Filtrate movement
Urine (to renal pelvis)

37. Line from artery to apparatus
Figure
Line from artery to apparatus
Pump
Tubing made of a selectively permeable membrane
Dialyzing solution
Line from apparatus to vein
Figure Kidney dialysis (part 1)
Fresh dialyzing solution
Used dialyzing solution (with urea and excess ions)

38. Figure
Figure Kidney dialysis (part 2)

39. Line from artery to apparatus
Figure
Line from artery to apparatus
Pump
Tubing made of a selectively permeable membrane
Dialyzing solution
Line from apparatus to vein
Figure Kidney dialysis
Fresh dialyzing solution
Used dialyzing solution (with urea and excess ions)

40. You should now be able to
Explain how emperor penguins are able to incubate eggs during Antarctic winters.
Describe four ways that heat is gained or lost by an animal.
Describe five categories of adaptations that help animals thermoregulate.
Compare the osmoregulatory problems of saltwater fish, freshwater fish, and terrestrial animals.
Compare the three ways that animals eliminate nitrogenous wastes.
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41. You should now be able to
Describe the structure and functions of the human kidney.
Explain how the kidney promotes homeostasis.
Explain how kidney filtrate is formed.
Describe the key events in the conversion of filtrate into urine.
Explain how antidiuretic hormone contributes to homeostasis.
Explain why a dialysis machine is necessary and how it works.
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42. which has four processes reproduction (where embryo develops)
Figure 25.UN04
Homeostasis
involves processes of
involves removal of
nitrogenous wastes
(a)
osmoregulation
maintains balance of
animal may be
form may be
(d)
(b)
(j)
(e)
done by
(k)
human kidney
mechanisms mostly
endotherm
(l)
depends on
mechanisms include
which has four processes
Figure 25.UN04 Connecting the concepts, question 1
(c)
environment
(f)
heat production, insulation, countercurrent heat exchange
may be
(g)
reproduction (where embryo develops)
(m)
(h)
(n)
(i)

43. (a) (b) (c) Bowman’s capsule From renal artery To renal vein
Figure 25.UN05
(a)
(b)
(c)
Bowman’s capsule
From renal artery
To renal vein
Collecting duct
Heat dissipation via radiation (blood vessel dilation) and convection (ear flapping)
Heat dissipation via radiation (blood vessel dilation) and convection (ear flapping)
Glomerulus
Tubule
Capillaries
Figure 25.UN05 Connecting the concepts, question 2
(d)

44. © 2015 Pearson Education, Inc.

45. Concept Check
A bear in its “long winter sleep” does not eat, expel solid wastes, or urinate. The ability to postpone urination for such a long period is a mystery. Urea and ammonia are the products produced when _______ and _______ are digested or metabolized. They are poisonous if allowed to accumulate.
carbohydrates, proteins
fats, carbohydrates
nucleic acids, proteins
nucleic acid, carbohydrates
Answer: c
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46. Answer
A bear in its “long winter sleep” does not eat, expel solid wastes, or urinate. The ability to postpone urination for such a long period is a mystery. Urea and ammonia are the products produced when _______ and _______ are digested or metabolized. They are poisonous if allowed to accumulate.
carbohydrates, proteins
fats, carbohydrates
nucleic acids, proteins
nucleic acid, carbohydrates
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47. Concept Check
Ducks and geese can stand on ice for hours without their feet freezing. To conserve body heat but still keep the feet functional, ducks and geese __________.
have outgoing blood vessels lying close to incoming blood vessels. This sets up a countercurrent heat exchange.
have antifreeze sugars in the tissues of their feet.
increase the flow of blood to the feet.
pull feathers from their breasts to stand on, insulating their feet from the ice.
Answer: a
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48. Answer
Ducks and geese can stand on ice for hours without their feet freezing. To conserve body heat but still keep the feet functional, ducks and geese __________.
have outgoing blood vessels lying close to incoming blood vessels. This sets up a countercurrent heat exchange.
have antifreeze sugars in the tissues of their feet.
increase the flow of blood to the feet.
pull feathers from their breasts to stand on, insulating their feet from the ice.
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49. Concept Check
Filtration of blood takes place in the _______ of the nephron.
proximal tubule
distal tubule
loop of Henle
Bowman’s capsule and glomerulus
Answer: d
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50. Answer Filtration of blood takes place in the _______ of the nephron.
Filtration of blood takes place in the _______ of the nephron.
proximal tubule
distal tubule
loop of Henle
Bowman’s capsule and glomerulus
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51. Concept Check
Which part of the nephron would you predict would receive the greatest damage from chronic hypertension (high blood pressure)?
proximal tubule
distal tubule
loop of Henle
Bowman’s capsule and glomerulus
Answer: d
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52. Answer
Which part of the nephron would you predict would receive the greatest damage from chronic hypertension (high blood pressure)?
proximal tubule
distal tubule
loop of Henle
Bowman’s capsule and glomerulus
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53. Thinking like a scientist
The human kidney concentrates urine in the nephrons and collecting ducts of the kidney. The nephron and collecting duct lie within interstitial fluid with a concentration gradient. The filtrate enters the nephron with an osmolarity of about 300.
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54. Thinking like a scientist
As the filtrate moves from A to B water diffuses out of the nephron and into the interstitial fluid. What would be the approximate osmolarity of the filtrate at point B?
300
400
1200
unchanged
Answer: c
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55. Answer
As the filtrate moves from A to B water diffuses out of the nephron and into the interstitial fluid. What would be the approximate osmolarity of the filtrate at point B?
300
400
1200
unchanged
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56. Thinking like a scientist
As the filtrate moves from B to C sodium ions diffuse and are actively transported into the interstitial fluid. By removing sodium ions but not water, what happens to the osmolarity of the filtrate from B to C?
The osmolarity increases.
The osmolarity decreases.
The osmolarity is unchanged.
Answer: b
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57. Answer
As the filtrate moves from B to C sodium ions diffuse and are actively transported into the interstitial fluid. By removing sodium ions but not water, what happens to the osmolarity of the filtrate from B to C?
The osmolarity increases.
The osmolarity decreases.
The osmolarity is unchanged.
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58. Thinking like a scientist
At point D the osmolarity of the filtrate is 300 or less—similar to blood. In order to conserve water, what happens to the osmolarity of the filtrate as it descends the duct, from D to E?
The osmolarity increases.
The osmolarity decreases.
The osmolarity is unchanged.
Answer: a
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59. Answer
At point D the osmolarity of the filtrate is 300 or less—similar to blood. In order to conserve water, what happens to the osmolarity of the filtrate as it descends the duct, from D to E?
The osmolarity increases.
The osmolarity decreases.
The osmolarity is unchanged.
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60. Science and Society
Over-the-counter pain relievers are safe and effective when taken in the correct dosages. However, their use is commonplace and, for many, part of everyday life. For this reason it is important to realize that like all medications there is risk involved. For example, everyday use of ibuprofen compounds increases the risk of internal bleeding and kidney damage. Acetaminophen when taken incorrectly can cause liver damage. Should the FDA require more extensive labeling of these over-the-counter drugs?
Disagree Agree
Strongly A B C D E Strongly
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61. Science and Society
Over-the-counter pain relievers are safe and effective when taken in the correct dosages. Do you currently read and follow the guidelines on over-the-counter pain relievers?
Strongly A B C D E Strongly
Disagree Agree
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62. Science and Society
Proper hydration is especially important during moderate exercise. Inadequate hydration creates a number of problems including longer recovery. Contrary to the information prevalent on sport drink commercials plain water is still the best source for rehydration. Sports drinks with added carbohydrates and electrolytes do come into play for more intensive exercise (1 hour or more). They are particularly important when the exercise is intense for many hours. Do you rely mostly on water for rehydration after exercise?
Strongly A B C D E Strongly
Disagree Agree
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