Download Chapter 40 - Basic Principles of Animal Form and Function

Figure 40.1
CAMPBELL
BIOLOGY
Figure 40.1a
Diverse Forms, Common Challenges
TENTH
EDITION
Reece • Urry • Cain • Wasserman • Minorsky • Jackson
!  Anatomy is the biological form of an organism
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!  Physiology is the biological functions an organism
performs
!  The comparative study of animals reveals that
form and function are closely correlated
Basic Principles
of Animal Form
and Function
Lecture Presentation by
Nicole Tunbridge and
Kathleen Fitzpatrick
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Concept 40.1: Animal form and function are
correlated at all levels of organization
Evolution of Animal Size and Shape
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Figure 40.2
!  Size and shape affect the way an animal interacts
with its environment
!  Physical laws govern strength, diffusion,
movement, and heat exchange
!  The body plan of an animal is programmed by the
genome, itself the product of millions of years of
evolution
!  Properties of water limit possible shapes for fast
swimming animals
Penguin
!  Convergent evolution often results in similar
adaptations of diverse organisms facing the same
challenge
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Tuna
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Figure 40.2b
Figure 40.2a
Seal
!  As animals increase in size, thicker skeletons are
required for support
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Seal
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Figure 40.2c
Exchange with the Environment
Penguin
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Tuna
!  Materials such as nutrients, waste products, and
gases must be exchanged across the cell
membranes of animal cells
!  A single-celled organism living in water has
sufficient surface area to carry out all necessary
exchange
!  Rate of exchange is proportional to a cell’s surface
area while amount of exchange material is
proportional to a cell’s volume
!  Multicellular organisms with a saclike body plan
have body walls that are only two cells thick,
facilitating diffusion of materials
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Figure 40.3
Figure 40.4
Video: Hydra Eating Daphnia
External environment
Exchange
Exchange
0.1 mm
(a) An amoeba, a single-celled
organism
Heart
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Cells
Circulatory
system
Lining of small
intestine (SEM)
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Lung tissue (SEM)
Interstitial
fluid
Nutrients
1 mm
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O2
Respiratory
system
!  Evolutionary adaptations such as specialized,
extensively branched or folded structures, enable
sufficient exchange with the environment
(b) A hydra, an animal with two
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layers of cells
CO2
Animal
body
!  More complex organisms are composed of
compact masses of cells with complex internal
organization
Exchange
Food
250 µm
!  In flat animals such as tapeworms, most cells are
in direct contact with its environment
Digestive
system
Anus
Unabsorbed
matter (feces)
Excretory
system
Blood vessels in
kidney (SEM)
Metabolic waste
products (nitrogenous waste)
50 µm
Gastrovascular
cavity
Mouth
100 µm
Mouth
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Figure 40.4a
Figure 40.4b
CO2
External
Food
O2
environment Mouth
Animal
body
Figure 40.4c
Figure 40.4d
Respiratory
system
Interstitial
fluid
Heart
Nutrients
Digestive
system
Anus
Unabsorbed
matter (feces)
Metabolic waste
products (nitrogenous waste)
Lung tissue (SEM)
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Blood vessels in
kidney (SEM)
50 µm
100 µm
Lining of small
intestine (SEM)
Excretory
system
250 µm
Cells
Circulatory
system
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Table 40.1
Table 40.1a
Hierarchical Organization of Body Plans
!  In vertebrates, the space between cells is filled
with interstitial fluid, which allows for the
movement of material into and out of cells
!  Most animals are composed of specialized cells
organized into tissues that have different
functions
!  A complex body plan helps an animal living in a
variable environment to maintain a relatively stable
internal environment
!  Tissues make up organs, which together make up
organ systems
!  Some organs, such as the pancreas, belong to
more than one organ system
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Table 40.1b
Exploring Structure and Function in Animal
Tissues
Epithelial Tissue
!  Different tissues have different structures that are
suited to their functions
!  Tissues are classified into four main categories:
epithelial, connective, muscle, and nervous
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!  It contains cells that are closely joined
!  The shape of epithelial cells may be cuboidal (like
dice), columnar (like bricks on end), or squamous
(like floor tiles)
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Figure 40.5a
!  The arrangement of epithelial cells may be simple
(single cell layer), stratified (multiple tiers of cells),
or pseudostratified (a single layer of cells of
varying length)
!  Epithelial tissue covers the outside of the body
and lines the organs and cavities within the body
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Figure 40.5aa
Epithelial Tissue
Stratified
squamous
epithelium
Lumen
Apical surface
Connective Tissue
Apical
surface
Basal
surface
Simple columnar
epithelium
Simple
squamous
epithelium
10 µm
Basal surface
Cuboidal
epithelium
Pseudostratified
columnar
epithelium
!  Collagenous fibers provide strength and flexibility
!  It contains sparsely packed cells scattered
throughout an extracellular matrix
!  Reticular fibers join connective tissue to adjacent
tissues
!  The matrix consists of fibers in a liquid, jellylike, or
solid foundation
!  Elastic fibers stretch and snap back to their original
length
Polarity of epithelia
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!  There are three types of connective tissue fiber, all
made of protein
!  Connective tissue mainly binds and supports
other tissues
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Figure 40.5b
Connective Tissue
Blood
Loose connective tissue
!  Cartilage is a strong and flexible support material
55 µm
30 µm
!  Fibrous connective tissue is found in tendons,
which attach muscles to bones, and ligaments,
which connect bones at joints
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Figure 40.5bb
Loose connective tissue
Adipose tissue
Central
canal
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Figure 40.5ba
Chondrocytes
Bone
Nuclei
700 µm
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Osteon
Fibrous connective tissue
Bone
Adipose tissue
Nuclei
Figure 40.5be
Osteon
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Fat droplets
150 µm
700 µm
120 µm
30 µm
Central
canal
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Figure 40.5bd
Collagenous fiber
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Fat droplets
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Figure 40.5bc
Elastic fiber
Red blood cells
Chondroitin sulfate
!  Bone is mineralized and forms the skeleton
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Cartilage
Elastic fiber
Fibrous connective tissue
100 µm
!  Macrophages that are involved in the immune
system
!  Blood is composed of blood cells and cell
fragments in blood plasma
!  Loose connective tissue binds epithelia to
underlying tissues and holds organs in place
Plasma
White
blood
cells
150 µm
!  Fibroblasts that secrete the protein of extracellular
fibers
!  In vertebrates, the fibers and foundation combine
to form six major types of connective tissue
120 µm
!  Connective tissue contains cells, including
Collagenous fiber
!  Adipose tissue stores fat for insulation and fuel
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Figure 40.5bf
Muscle Tissue
Blood
Cartilage
Plasma
Chondrocytes
100 µm
55 µm
White
blood
cells
!  It is divided in the vertebrate body into three types
!  Muscle tissue is responsible for nearly all types of
body movement
!  Skeletal muscle, or striated muscle, is responsible
for voluntary movement
!  Muscle cells consist of filaments of the proteins
actin and myosin, which together enable muscles
to contract
!  Smooth muscle is responsible for involuntary body
activities
!  Cardiac muscle is responsible for contraction of
the heart
Chondroitin sulfate
Red blood cells
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Figure 40.5c
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Figure 40.5ca
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Figure 40.5cb
Figure 40.5cc
Muscle Tissue
Skeletal muscle
Nuclei
Nuclei
Sarcomere
100 µm
Muscle
fiber
Smooth muscle
Cardiac muscle
Sarcomere
Nucleus
100 µm
Nucleus
Muscle
fibers
25 µm
Nucleus Intercalated
disk
Muscle fibers
Nucleus Intercalated disk
25 µm
25 µm
25 µm
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Cardiac muscle
Smooth muscle
Skeletal muscle
Muscle
fiber
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Figure 40.5d
Figure 40.5da
Video: Cardiac Muscle Contraction
Neurons
Neuron:
Nervous Tissue
Nervous Tissue
Glia
Neurons
Neuron:
Dendrites
Cell body
!  Nervous tissue contains
40 µm
(Fluorescent LM)
!  Glial cells, or glia, support cells
15 µm
Cell body
Axon
Axons of
neurons
Axon
!  Neurons, or nerve cells, that transmit nerve
impulses
Glia
Blood
vessel
40 µm
!  Nervous tissue functions in the receipt,
processing, and transmission of information
Dendrites
(Confocal LM)
(Fluorescent LM)
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Figure 40.5db
Figure 40.6
Glia
15 µm
Glia
Figure 40.6a
(a) Signaling by hormones
Coordination and Control
STIMULUS
(a) Signaling by hormones
STIMULUS
Signal travels
everywhere.
Blood
vessel
!  A hormone may affect one or more regions
throughout the body
Cell body
of neuron
Signal travels
to a specific
location.
Hormone
Nerve
impulse
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Blood
vessel
Response
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Nerve
impulse
Signal travels
everywhere.
Axons
!  Hormones are relatively slow acting, but can have
long-lasting effects
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STIMULUS
Endocrine
cell
Axon
Nerve
impulse
Hormone
(Confocal LM)
(b) Signaling by neurons
STIMULUS
Cell body
of neuron
!  The endocrine system transmits chemical signals
called hormones to receptive cells throughout the
body via blood
Blood
vessel
(b) Signaling by neurons
Endocrine
cell
!  Control and coordination within a body depend on
the endocrine system and the nervous system
Axons of
neurons
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Response
Axon
Signal travels
to a specific
location.
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Concept 40.2: Feedback control maintains the
internal environment in many animals
Regulating and Conforming
Figure 40.6b
(a) Signaling by hormones
Blood
vessel
(b) Signaling by neurons
!  The nervous system transmits information
between specific locations
Nerve
impulse
!  Faced with environmental fluctuations, animals
manage their internal environment by either
regulating or conforming
!  The information conveyed depends on a signal’s
pathway, not the type of signal
Axons
!  A regulator uses internal control mechanisms to
control internal change in the face of external
fluctuation
!  A conformer allows its internal condition to vary
with certain external changes
!  Nerve signal transmission is very fast
!  Animals may regulate some environmental
variables while conforming to others
Response
Response
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Figure 40.7
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Figure 40.7a
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Figure 40.7b
Figure 40.7c
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Body temperature (°C)
River otter (temperature regulator)
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Body temperature (°C)
River otter (temperature regulator)
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20
Largemouth bass
(temperature conformer)
10
0
0
20
Largemouth bass
(temperature conformer)
10
0
10
20
30
40
Ambient (environmental)
temperature (°C)
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0
10
20
30
40
Ambient (environmental)
temperature (°C)
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Figure 40.8
Homeostasis
Mechanisms of Homeostasis
!  Organisms use homeostasis to maintain a
“steady state” or internal balance regardless of
external environment
Animation: Negative Feedback
!  Mechanisms of homeostasis moderate changes in
the internal environment
Thermostat turns
heater off.
Room temperature
Room temperature
increases.
decreases.
!  For a given variable, fluctuations above or below a
set point serve as a stimulus; these are detected
by a sensor and trigger a response
!  In humans, body temperature, blood pH, and
glucose concentration are each maintained at a
constant level
ROOM
TEMPERATURE
AT 20°C (set point)
!  The response returns the variable to the set point
Room temperature
increases.
Room temperature
decreases.
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Animation: Positive Feedback
Feedback Control in Homeostasis
Alterations in Homeostasis
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!  Homeostasis in animals relies largely on negative
feedback, which helps to return a variable to a
normal range
!  Positive feedback amplifies a stimulus and does
not usually contribute to homeostasis in animals
Core body temperature (°C)
Figure 40.9
!  Set points and normal ranges can change with age
or show cyclic variation
Body
temperature
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36.9
40
20
36.7
36.5
!  In animals and plants, a circadian rhythm
governs physiological changes that occur roughly
every 24 hours
Melatonin
concentration
37.1
2
PM
6
PM
10
PM
AM
AM
10
0
AM
Time of day
Midnight
Greatest
muscle
strength
6 AM
Most rapid
rise in blood
pressure
Fastest
reaction time
Noon
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Lowest
heart rate
Lowest body
temperature
6 PM
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6
(a) Variation in core body temperature and melatonin
concentration in blood
Start of
melatonin secretion
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2
Melatonin concentration
in blood (pg/mL)
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Thermostat
turns heater on.
Highest risk
of cardiac arrest
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(b) The human circadian clock
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Body
temperature
Melatonin
concentration
37.1
60
36.9
40
36.7
20
36.5
0
2
PM
6
PM
10
PM
2
AM
6
AM
10
Melatonin concentration
in blood (pg/mL)
Figure 40.9b
Core body temperature (°C)
Figure 40.9a
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Figure 40.10
Start of
melatonin secretion
Midnight
Greatest
muscle
strength
Lowest body
temperature
6 AM
6 PM
Most rapid
rise in blood
pressure
Fastest
reaction time
AM
Noon
Time of day
!  Homeostasis can adjust to changes in external
environment, a process called acclimatization
Lowest
heart rate
Highest risk
of cardiac arrest
(b) The human circadian clock
(a) Variation in core body temperature and melatonin
concentration in blood
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Concept 40.3: Homeostatic processes for
thermoregulation involve form, function, and
behavior
Endothermy and Ectothermy
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Figure 40.11
!  Endothermic animals generate heat by
metabolism; birds and mammals are endotherms
!  Thermoregulation is the process by which
animals maintain an internal temperature within a
tolerable range
!  Endotherms can maintain a stable body
temperature even in the face of large fluctuations
in environmental temperature
!  Ectothermic animals gain heat from external
sources; ectotherms include most invertebrates,
fishes, amphibians, and nonavian reptiles
!  Endothermy is more energetically expensive than
ectothermy
!  In general, ectotherms tolerate greater variation in
internal temperature
(a) A walrus, an endotherm
(b) A lizard, an ectotherm
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Figure 40.11a
Figure 40.11b
Variation in Body Temperature
Balancing Heat Loss and Gain
!  The body temperature of a poikilotherm varies with
its environment
!  The body temperature of a homeotherm is
relatively constant
!  Organisms exchange heat by four physical
processes: radiation, evaporation, convection, and
conduction
!  The relationship between heat source and body
temperature is not fixed (that is, not all
poikilotherms are ectotherms)
(b) A lizard, an ectotherm
(a) A walrus, an endotherm
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Figure 40.12
Radiation
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Evaporation
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Insulation
Circulatory Adaptations
!  Heat regulation in mammals often involves the
integumentary system: skin, hair, and nails
!  Insulation is a major thermoregulatory adaptation
in mammals and birds
!  Regulation of blood flow near the body surface
significantly affects thermoregulation
!  Five adaptations help animals thermoregulate
!  Skin, feathers, fur, and blubber reduce heat flow
between an animal and its environment
!  Many endotherms and some ectotherms can alter
the amount of blood flowing between the body
core and the skin
!  Insulation
!  Insulation is especially important in marine
mammals such as whales and walruses
!  Circulatory adaptations
!  In vasodilation, blood flow in the skin increases,
facilitating heat loss
!  Cooling by evaporative heat loss
!  Behavioral responses
!  In vasoconstriction, blood flow in the skin
decreases, lowering heat loss
!  Adjusting metabolic heat production
Convection
Conduction
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Figure 40.13
!  The arrangement of blood vessels in many marine
mammals and birds allows for countercurrent
exchange
!  Countercurrent heat exchangers transfer heat
between fluids flowing in opposite directions and
thereby reduce heat loss
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Artery
Cooling by Evaporative Heat Loss
Bottlenose
dolphin
Canada
goose
1
3
Vein
Vein
35°C
33°
30°
27°
20°
18°
10°
9°
3
Artery
3
!  Some bony fishes and sharks also use
countercurrent heat exchanges
!  Many types of animals lose heat through
evaporation of water from their skin
!  Many endothermic insects have countercurrent
heat exchangers that help maintain a high
temperature in the thorax
!  Sweating or bathing moistens the skin, helping to
cool an animal down
!  Panting increases the cooling effect in birds and
many mammals
2
Key
2
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Warm blood
Cool blood
Blood flow
Heat transfer
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Figure 40.14
Figure 40.15
Behavioral Responses
Adjusting Metabolic Heat Production
PREFLIGHT
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!  Thermogenesis is the adjustment of metabolic
heat production to maintain body temperature
!  Some terrestrial invertebrates have postures that
minimize or maximize absorption of solar heat
!  Thermogenesis is increased by muscle activity
such as moving or shivering
!  Honeybees huddle together during cold weather to
retain heat
!  Nonshivering thermogenesis takes place when
hormones cause mitochondria to increase their
metabolic activity
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Abdomen
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Abdomen
25
0
2
Time from onset of warm-up (min)
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Thorax
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!  Some ectotherms can also shiver to increase body
temperature
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FLIGHT
Thorax
Temperature (°C)
!  Both endotherms and ectotherms use behavioral
responses to control body temperature
PREFLIGHT
WARM-UP
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Figure 40.16
Figure 40.17
Results
Acclimatization in Thermoregulation
Thermostat in
hypothalamus
activates cooling
mechanisms.
Physiological Thermostats and Fever
O2 consumption (mL O2/hr•kg)
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!  Birds and mammals can vary their insulation to
acclimatize to seasonal temperature changes
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!  Thermoregulation in mammals is controlled by a
region of the brain called the hypothalamus
!  When temperatures are subzero, some
ectotherms produce “antifreeze” compounds to
prevent ice formation in their cells
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5
10
15
20
25
30
Contractions per minute
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Figure 40.17a
Body temperature
decreases.
NORMAL BODY
TEMPERATURE
(approximately
36–38°C)
!  Fever, a response to some infections, reflects an
increase in the normal range for the biological
thermostat
20
0
Response:
Sweat
Body temperature
increases.
!  The hypothalamus triggers heat loss or heat
generating mechanisms
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0
Response: Blood
vessels in skin dilate.
Body temperature
decreases.
Body temperature
increases.
Response: Shivering
!  Some ectothermic organisms seek warmer
environments to increase their body temperature
in response to certain infections
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Response: Blood
vessels in skin
constrict.
Thermostat in
hypothalamus
activates warming
mechanisms.
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Concept 40.4: Energy requirements are related
to animal size, activity, and environment
Energy Allocation and Use
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Figure 40.17b
Thermostat in
hypothalamus
activates cooling
mechanisms.
NORMAL BODY
TEMPERATURE
(approximately
36–38°C)
Response: Blood
vessels in skin dilate.
Response:
Sweat
Body temperature
increases.
Body temperature
decreases.
Body temperature
increases.
Body temperature
decreases.
Response: Shivering
Response: Blood
vessels in skin
constrict.
NORMAL BODY
TEMPERATURE
(approximately
36–38°C)
!  Organisms can be classified by how they obtain
chemical energy
!  It determines how much food an animal needs and
it relates to an animal’s size, activity, and
environment
!  Autotrophs, such as plants, harness light energy to
build energy-rich molecules
Thermostat in
hypothalamus
activates warming
mechanisms.
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!  Bioenergetics is the overall flow and
transformation of energy in an animal
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Figure 40.19
Quantifying Energy Use
Organic molecules
in food
External
environment
Animal
body
Digestion and
absorption
!  Metabolic rate is the amount of energy an animal
uses in a unit of time
Heat
Energy lost
in feces
Nutrient molecules
in body cells
!  After the needs of staying alive are met, remaining
food molecules can be used in biosynthesis
Carbon
skeletons
!  Biosynthesis includes body growth and repair,
synthesis of storage material such as fat, and
production of gametes
Cellular
respiration
!  Metabolic rate can be determined by
Energy lost in
nitrogenous
waste
!  An animal’s heat loss
Heat
!  The amount of oxygen consumed or carbon dioxide
produced
ATP
!  Measuring energy content of food consumed and
energy lost in waste products
Biosynthesis
Cellular
work
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Figure 40.18
!  Energy-containing molecules from food are usually
used to make ATP, which powers cellular work
!  Heterotrophs, such as animals, harvest chemical
energy from food
Heat
Heat
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Minimum Metabolic Rate and Thermoregulation
Influences on Metabolic Rate
Size and Metabolic Rate
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Figure 40.20
!  Standard metabolic rate (SMR) is the metabolic
rate of an ectotherm at rest at a specific
temperature
!  Some key factors are age, sex, size, activity,
temperature, and nutrition
!  Metabolic rate is proportional to body mass to the
power of three quarters (m3/4)
!  Smaller animals have higher metabolic rates per
gram than larger animals
!  The higher metabolic rate of smaller animals leads
to a higher oxygen delivery rate, breathing rate,
heart rate, and greater (relative) blood volume,
compared with a larger animal
!  Both rates assume a nongrowing, fasting, and
nonstressed animal
!  Ectotherms have much lower metabolic rates than
endotherms of a comparable size
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10 3
10
Dog
Cat
1
10
−1
Rat
Ground squirrel
Shrew
Mouse
Harvest mouse
10 −2
10 −3
10 −2
10 −1
1
10
Shrew
7
Human
Sheep
6
5
4
3
Harvest mouse
2
1
10 2
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Body mass (kg) (log scale)
(a) Relationship of basal metabolic rate (BMR) to body
size for various mammals
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Elephant
Horse
10 2
BMR (L O2/hr•kg)
!  Metabolic rates are affected by many factors
besides whether an animal is an endotherm or
ectotherm
BMR (L O2/hr) (log scale)
!  Basal metabolic rate (BMR) is the metabolic rate
of an endotherm at rest at a “comfortable”
temperature
Ground
squirrel
0
10 −3
10
−2
Sheep
Mouse
Elephant
Human
Rat Cat
Dog
Horse
10 −1
1
10
10 2
103
Body mass (kg) (log scale)
(b) Relationship of BMR per kilogram of body mass to
body size
112
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Figure 40.20a
Figure 40.20b
103
Dog
Cat
1
Rat
Ground squirrel
Shrew
Mouse
Harvest mouse
10−2
10−3
10−2
10−1
1
10
!  Activity greatly affects metabolic rate for
endotherms and ectotherms
6
BMR (L O2/hr•kg)
BMR (L O2/hr) (log scale)
Human
Sheep
10
Shrew
7
Horse
102
10−1
Activity and Metabolic Rate
8
Elephant
5
3
Harvest mouse
2
1
102
Sheep
Elephant
Human
Cat
Dog
Horse
Mouse
Rat
Ground
squirrel
0
10−3
103
10 −2
10−1
1
10
102
!  The fraction of an animal’s energy budget devoted
to activity depends on factors such as
environment, behavior, size, and thermoregulation
10 3
Body mass (kg) (log scale)
Body mass (kg) (log scale)
(a) Relationship of basal metabolic rate (BMR) to body
size for various mammals
!  In general, the maximum metabolic rate an animal
can sustain is inversely related to the duration of
the activity
4
!  For most terrestrial animals, the average daily rate
of energy consumption is 2–4 times BMR
(endotherms) or SMR (ectotherms)
(b) Relationship of BMR per kilogram of body mass to
body size
113
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114
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115
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116
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Figure 40.21
Torpor and Energy Conservation
Results
Day
!  Torpor is a physiological state in which activity is
low and metabolism decreases
Relative RNA level (%)
Per2
!  Torpor enables animals to save energy while
avoiding difficult and dangerous conditions
!  Hibernation is long-term torpor that is an
adaptation to winter cold and food scarcity
100
60
!  There are also some fundamental similarities in
the evolutionary adaptations of plants and animals
20
0
Euthermia Hibernation
Euthermia Hibernation
118
Figure 40.22aa
MAKE CONNECTIONS: Life Challenges and Solutions in
Plants and Animals
Environmental Response
!  There are many aspects to the relationship
between structure and function in animals
40
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Figure 40.22a
!  Summer torpor, called estivation, enables animals
to survive long periods of high temperatures and
scarce water
!  Daily torpor is exhibited by many small mammals
and birds and seems adapted to feeding patterns
80
117
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Night
Bmal1
119
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Figure 40.22aaa
Environmental Response
120
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Figure 40.22aab
Environmental Response
Nutritional Mode
Environmental Response
Growth and Regulation
An insect’s eyes contain
photoreceptors that detect
light.
The floral head of a sunflower (left) and an insect’s eyes
(right) both contain photoreceptors that detect light.
121
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Figure 40.22ab
Figure 40.22aba
Nutritional Mode
123
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Figure 40.22abb
Nutritional Mode
124
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Figure 40.22ac
Growth and Regulation
Nutritional Mode
The broad surface of many leaves (left) enhances light capture for
photosynthesis. When hunting, a bobcat relies on stealth, speed, and sharp
125
claws (right).
© 2014 Pearson Education, Inc.
The floral head of a sunflower contains
photoreceptors that detect light.
122
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The broad surface of many leaves
enhances light capture for photosynthesis.
© 2014 Pearson Education, Inc.
When hunting, a bobcat relies on stealth, speed, and
sharp claws.
126
127
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In plants, hormones control growth patterns, flowering, fruit development,
and more (left). In animals, hormones control developmental events such128
as molting (right).
© 2014 Pearson Education, Inc.
Figure 40.22aca
Figure 40.22acb
Figure 40.22b
Figure 40.22ba
MAKE CONNECTIONS: Life Challenges and Solutions in
Plants and Animals
Transport
Reproduction
Transport
Growth and Regulation
Growth and Regulation
Gas Exchange
Absorption
In plants, hormones control growth
patterns, flowering, fruit development,
and more.
In animals, hormones control developmental
events such as molting.
129
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Figure 40.22baa
130
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Figure 40.22bab
Transport
132
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Figure 40.22bb
Figure 40.22bba
Reproduction
Transport
Plants harness solar energy to transport water,
minerals, and sugars through specialized tubes (left).
in animals, a pump (heart) moves circulatory fluid
through vessels (right).
131
Reproduction
Plants harness solar energy
to transport water, minerals,
and sugars through
specialized tubes.
133
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Figure 40.22bbb
Seeds have stored food reserves that
supply energy to the young seedling.
134
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Figure 40.22bc
Reproduction
Milk provides sustenance for
juvenile mammals.
Figure 40.22bca
Absorption
135
Figure 40.22bcb
Absorption
Absorption
The villi (projections) that line
the intestines of vertebrates
increase the surface area
available for absorption.
139
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Figure 40.22bda
136
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The root hairs of
plants increase the
surface area available
for absorption.
138
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Gas Exchange
Seeds (left) have stored food reserves that supply energy to the
young seedling, while milk provides sustenance for juvenile
mammals (right).
© 2014 Pearson Education, Inc.
The root hairs of plants (left) and the villi (projections)
that line the intestines of vertebrates (right) increase
the surface area available for absorption.
137
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Figure 40.22bd
In animals, a pump (heart)
moves circulatory fluid
through vessels.
Figure 40.22bdb
Figure 40.UN01
Gas Exchange
Gas Exchange
Adélie penguin
4-kg male
340,000 kcal/yr
In plants, highly convoluted
surfaces have evolved, such as
the spongy mesophyll of leaves.
In both plants and animals, highly convoluted surfaces have
evolved, such as the spongy mesophyll of leaves (left) and
the alveoli of lungs (right).
© 2014 Pearson Education, Inc.
In animals, highly convoluted
surfaces have evolved, such as
the alveoli of lungs.
142
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Basal (standard) metabolism
143
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Deer mouse
0.025-kg female
4,000 kcal/yr
Ball python
4-kg female
8,000 kcal/yr
Key
Reproduction
141
140
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Thermoregulation
© 2014 Pearson Education, Inc.
Activity
Growth
144
Figure 40.UN02
Figure 40.UN03
Figure 40.UN04
NORMAL RANGE
for internal variable
Response
Hibernating dormouse
(Muscardinus avellanarius)
Control center
145
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Stimulus: change in
internal variable
Sensor
146
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147
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