1. How does a jackrabbit keep from overheating?
Figure 40.1 How does a jackrabbit keep from overheating?
For the Discovery Video Human Body, go to Animation and Video Files.

2. Convergent evolution in fast swimmers
(a) Tuna
Figure 40.2 Convergent evolution in fast swimmers
(b) Penguin
(c) Seal

3. Contact with the environment
Mouth
Gastrovascular
cavity
Exchange
Exchange
Exchange
Figure 40.3 Contact with the environment
0.15 mm
1.5 mm
(a) Single cell
(b) Two layers of cells

4. Internal exchange surfaces of complex animals
External environment
CO2
Food O2
Mouth
Animal
body
Respiratory
system
Blood
50 µm
0.5 cm
Lung tissue
Nutrients
Cells
Heart
Circulatory
system
10 µm
Interstitial
fluid
Digestive
system
Figure 40.4 Internal exchange surfaces of complex animals
Lining of small intestine
Excretory
system
Kidney tubules
Anus
Unabsorbed
matter (feces)
Metabolic waste products
(nitrogenous waste)

5. Organ Systems

6. Structure and function in animal tissues
Epithelial Tissue
Cuboidal
epithelium
Simple
columnar
epithelium
Pseudostratified
ciliated
columnar
epithelium
Stratified
squamous
epithelium
Figure 40.5 Structure and function in animal tissues
Simple
squamous
epithelium

7. Connective Tissue Loose connective tissue Cartilage Fibrous connective
Collagenous fiber
Loose
connective
tissue
Chondrocytes
Cartilage
120 µm
100 µm
Elastic fiber
Chondroitin
sulfate
Nuclei
Fat droplets
Fibrous
connective
tissue
Adipose
tissue
30 µm
150 µm
Figure 40.5 Structure and function in animal tissues
Osteon
White blood cells
Bone
Blood
700 µm
55 µm
Central canal
Plasma
Red blood
cells

8. Muscle Tissue Skeletal muscle Cardiac muscle Smooth muscle Multiple
nuclei
Muscle fiber
Sarcomere
Skeletal
muscle
Nucleus
100 µm
Intercalated
disk
50 µm
Cardiac muscle
Figure 40.5 Structure and function in animal tissues
Smooth
muscle
Nucleus
Muscle
fibers
25 µm

9. Nervous Tissue Neuron 40 µm Axons Blood vessel Dendrites Cell body
Glial cells
Neuron
Figure 40.5 Structure and function in animal tissues
Axons
Blood vessel
15 µm

10. Neuron 40 µm Dendrites Cell body Axon
Figure 40.5 Structure and function in animal tissues
Neuron

11. Signaling Stimulus Stimulus Endocrine cell Neuron Axon Signal Hormone
Signal travels
along axon to
a specific
location.
Signal travels
everywhere
via the
bloodstream.
Blood
vessel
Signal
Axons
Figure 40.6 Signaling in the endocrine and nervous systems
Response
Response
(a) Signaling by hormones
(b) Signaling by neurons

12. Stimulus Neuron Axon Signal Signal travels along axon to a specific
location.
Signal
Axons
Figure 40.6b Signaling in the endocrine and nervous systems
Response
Signaling by neurons

13. (temperature conformer)40
River otter (temperature regulator) 30
Body temperature (°C) 20
Largemouth bass
(temperature conformer) 10
Figure 40.7 The relationship between body and environmental temperatures in an aquatic temperature regulator and an aquatic temperature conformer 10 20 30 40
Ambient (environmental) temperature (ºC)

14. negative feedback Response: Heater turned off Room temperature
decreases
Stimulus:
Control center
(thermostat)
reads too hot
Set
point:
20ºC
Figure 40.8 A nonliving example of negative feedback: control of room temperature
Stimulus:
Control center
(thermostat)
reads too cold
Room
temperature
increases
Response:
Heater
turned on

15. (a) A walrus, an endotherm
Figure 40.9 Endothermy and ectothermy
(b) A lizard, an ectotherm

16. Heat exchange between an organism and its environment
Radiation
Evaporation
Figure Heat exchange between an organism and its environment
Convection
Conduction

17. Mammalian integumentary system
Hair
Epidermis
Sweat
pore
Dermis
Muscle
Nerve
Sweat
gland
Figure Mammalian integumentary system
Hypodermis
Adipose tissue
Blood vessels
Oil gland
Hair follicle

18. Countercurrent heat exchangers
Canada goose
Bottlenose
dolphin
Blood flow
Artery
Vein
Vein
Artery
35ºC
33º
Figure Countercurrent heat exchangers
30º
27º
20º
18º
10º 9º
Countercurrent heat exchangers

19. O2 consumption (mL O2/hr) per kg
RESULTS
A Burmese python generates heat while incubating eggs.
120
100 80
O2 consumption (mL O2/hr) per kg 60 40
Figure How does a Burmese python generate heat while incubating eggs? 20 5 10 15 20 25 30 35
Contractions per minute

20. Hypothalamus: thermoregulation
Sweat glands secrete sweat, which evaporates, cooling the body.
Thermostat in hypothalamus activates cooling mechanisms.
Hypothalamus: thermoregulation
Blood vessels in skin dilate: capillaries fill; heat radiates from skin.
Body temperature decreases; thermostat shuts off cooling mechanisms.
Increased body temperature
Homeostasis: Internal temperature of 36–38°C
Body temperature increases; thermostat shuts off warming mechanisms.
Decreased body temperature
Figure The thermostatic function of the hypothalamus in human thermoregulation
Blood vessels in skin constrict, reducing heat loss.
Thermostat in hypothalamus activates warming mechanisms.
Skeletal muscles contract; shivering generates heat.

21. Bioenergetics of an animal
Organic molecules
in food
Bioenergetics of an animal
External
environment
Animal
body
Digestion and
absorption
Heat
Energy lost
in feces
Nutrient molecules
in body cells
Energy lost in
nitrogenous
waste
Carbon
skeletons
Cellular
respiration
Heat
Figure Bioenergetics of an animal: an overview
ATP
Biosynthesis
Cellular
work
Heat
Heat

22. Relationship of Metabolic Rate to Body Size
103
Elephant
102
Horse
Human 10
Sheep
BMR (L O2/hr) (Iog scale)
Cat
Dog 1
Rat
10–1
Ground squirrel
Shrew
Mouse
Harvest mouse
10–2
10–3
10–2
10–1 1 10
102
103
Body mass (kg) (log scale)
(a) Relationship of BMR to body size 8
Shrew 7 6
Figure The relationship of metabolic rate to body size 5
BMR (L O2/hr) (per kg) 4 3
Harvest mouse 2
Mouse
Sheep
Rat
Human
Elephant 1
Cat
Dog
Ground squirrel
Horse
10–3
10–2
10–1 1 10
102
103
Body mass (kg) (log scale)
(b) Relationship of BMR per kilogram of body mass to body size

23. from temperate climate
Energy budgets for four animals
Endotherms
Ectotherm
800,000
Reproduction
Basal
(standard)
metabolism
Thermoregulation
Growth
Activity
Annual energy expenditure (kcal/hr)
340,000
8,000
4,000
Figure Energy budgets for four animals
60-kg female human
from temperate climate
4-kg male Adélie penguin
from Antarctica (brooding)
0.025-kg female deer mouse
from temperate
North America
4-kg female eastern
indigo snake

24. Body temperature and metabolism during hibernation in ground squirrels
Additional metabolism that would be
necessary to stay active in winter
200
Actual
metabolism
Metabolic rate
(kcal per day)
100
Arousals 35
Body
temperature 30 25 20
Temperature (°C) 15 10
Figure Body temperature and metabolism during hibernation in Belding’s ground squirrels 5
Outside
temperature –5
Burrow
temperature
–10
–15
June
August
October
December
February
April

25. Stimulus: Perturbation/stress
Review
Homeostasis
Response/effector
Stimulus:
Perturbation/stress
Control center
Sensor/receptor

26. You should now be able to:
Distinguish among the following sets of terms: collagenous, elastic, and reticular fibers; regulator and conformer; positive and negative feedback; basal and standard metabolic rates; torpor, hibernation, estivation, and daily torpor.
Relate structure with function and identify diagrams of the following animal tissues: epithelial, connective tissue (six types), muscle tissue (three types), and nervous tissue.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

27. Compare and contrast the nervous and endocrine systems.
Define thermoregulation and explain how endotherms and ectotherms manage their heat budgets.
Describe how a countercurrent heat exchanger may function to retain heat within an animal body.
Define bioenergetics and biosynthesis.
Define metabolic rate and explain how it can be determined for animals.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings