Animal Structure and
Function
Functional Anatomy
• Animal adaptations evolved through
time by natural selection.
• Can also adapt over short periods
of time.
• Chemical energy needed for
searching for food, generating body
heat, regulating internal
temperature, etc..
http://www.no-pest.com/CruisinForaBruisin'.JPG
• Bioenergetics - how organisms
obtain, process, and use their
energy resources.
• All animals have correlation
between form (anatomy) and
function (physiology).
http://shs.westport.k12.ct.us/mjvl/anatomy/jugglers.gif
• Tissues make up organs, organs 
organ systems  organisms.
• Tissues - groups of cells with
common structure and function.
• 4 types of tissues: epithelial,
connective, muscle, nervous.
http://www.emc.maricopa.edu/faculty/farabee/biobk/stomTS.gif
• 1Epithelial – covers body, lines
organs and cavities in body.
• Cells joined tightly together.
• Prevents fluid loss, invasion of
microorganisms.
• Attached to underlying tissue by
basement membrane.
http://www.uoguelph.ca/zoology/devobio/miller/01362fig6-1.gif
• ASimple epithelium – single-layered.
• BStratified – multi-layered.
• Shapes – cuboidal, columnar,
sqamous (flattened)
• Glandular – secretes fluid – can line
respiratory system (produces
mucous)
• 2Connective tissue – binds, supports
other tissue.
• Cells scattered throughout matrix.
• Matrix made of fibers.
• 3 types of fibers – 1collagenous
(collagen – tough), 2elastic (elastin,
flexible), 3reticular (thin and
branched – connect to adjoining
tissues)
Reticular fibers
http://www.mhhe.com/biosci/ap/histology_mh/reticct.jpg
• Major types - loose connective
tissue, adipose tissue, fibrous
connective tissue, cartilage, bone,
and blood.
• ALoose connective - packing
materials, holding organs in place.
• 2 cell types – 1Fibroblasts (secrete
proteins), 2Macrophages (engulf
bacteria)
http://www.sci.sdsu.edu/histology/hi_res/jpg/ct01oh.jpg
• BAdipose - insulates body, stores
fuel as fat molecules.
• Contains large fat droplet that
swells when fat is stored, shrinks
when body uses fat as fuel.
http://www.deltagen.com/target/histologyatlas/atlas_files/musculoskeletal/adipose_tissue_white_40x.jpg
• CFibrous connective - forms
tendons (muscles to bones) and
ligaments (bones to bones at joints)
• DCartilage - flexible supports in
certain locations, such as the nose,
ears, and vertebral disks.
• Chondrocytes secrete collagen.
http://www.mhhe.com/biosci/ap/histology_mh/hcart.jpg
• EBone - mineralized connective
tissue.
• Osteoblasts deposit a matrix of
collagen.
• Bones consists of repeating units
called osteons – has nerves and
blood vessels.
http://www.texarkanacollege.edu/~mstorey/1407/bone.jpg
• FBlood - matrix liquid (plasma) has
water, salts, variety of dissolved
proteins.
• Suspended in plasma erythrocytes
(red blood cells – carry oxygen),
leukocytes (white blood cells – fight
invaders) cell fragments (platelets –
clotting)
http://www.kumc.edu/instruction/medicine/anatomy/histoweb/blood/large/Blood000.JPG
• 3Nervous - senses stimuli, transmits
signals from one part of animal to
another; functional unit – neuron
• Consists of cell body, 2+ extensions
(dendrites + axons)
• Dendrites transmit nerve impulses
from tips toward rest of neuron.
• Axons impulses toward another
neuron or effector (muscle cell)
• 4Muscle – composed of muscle
fibers capable of contracting when
stimulated by nerve impulses.
• Fibers consist of contractile
proteins actin and myosin.
• 3 types – skeletal, cardiac, smooth.
• ASkeletal – responsible for
voluntary movement; striated.
• BSmooth – no striations; found in
walls of digestive tract, urinary
bladder, arteries, other internal
organs – involuntary.
• CCardiac – striated and branched;
forms walls of heart muscle. Cells
joined by intercalated discs;
involuntary.
http://www.lima.ohio-state.edu/academics/biology/images/anatomy/Smooth%20Muscle%20400X.jpg
Functional Anatomy
• Tissues organized into organs.
• Mammals – thoracic cavity – lungs,
heart – separated from abdomen by
diaphragm.
• Tissues can be arranged in layers.
• Organ systems carry out major
body functions.
Body Plans
• Animal’s size and shape - body
plans.
• Physical requirements constrain
natural selection.
• Laws of hydrodynamics constrain
shapes possible for aquatic
organisms that swim very fast.
• Animals shape, size, determine how
animal exchanges materials with
surroundings.
• Protist living in water – plasma
membrane large to exchange
materials through diffusion.
• Multicellular organisms – many
smaller cells able to exchange
materials through each one.
• Flat body – maximizes exposure to
surroundings; prevents internal
complexity.
• Most animals complex – cells small
compared to volume.
• Allows animal to not be tied to land.
• Internal organs can regulate body.
Regulating Internal Environment
• Internal environment of
vertebrates – interstitial fluid.
• Exchanges nutrients and wastes.
• Animals maintain homeostasis
(internal balance) even when
external environment changes.
http://titlev.fiu.edu/homeostasis/images/homeostasis_home.jpg
• Major internal changes are
programmed to occur, such as
during pregnancy.
• Homeostatic control system has 3
parts: receptor, control center,
effector.
• 1Receptor – detects change in
environment.
• 2Control center – processes change.
• 3Effector – directs response.
• Two types – 1Negative feedback
control – change causes reaction in
opposite direction.
• Fever – causes body to sweat to
bring temperature down.
• 2Positive – change causes reaction
in same direction.
• Labor – release in oxytocin
increases uterine contractions.
• Regulated change important to
survival.
• Can by cyclical (hormones), or
reactive (fever)
• Internal regulation expensive in
energy.
http://web.lemoyne.edu/~hevern/psy340/graphics/negative.feedback.jpg
Bioenergetics
• Chemical energy needed for growth,
repair, regulation, reproduction.
• Food digested through hydrolysis,
nutrients absorbed by cells.
• ATP use creates heat that is lost to
environment.
• Energy left over – used for
bioenergetics.
http://www.topicazos.com/fotos/digestion.jpg
• Bioenergetics - synthesis of
storage material, production of
reproductive structures, including
gametes.
• Flow of energy through animal –
sets limits on growth, behavior,
reproduction, energy needs.
• Amount of energy used in given
time – metabolic rate.
• Measured in calories.
• Metabolic rate can be determined
by measuring amount of heat
produced.
• 2 metabolic strategies used by
animals.
http://www.nsf.gov/news/speeches/colwell/rc01aibs/img004.jpg
• 1Endothermic – birds, mammals maintain body temperature at
certain level with heat generated
by metabolism.
• High-energy strategy – allows for
intense activity.
• 2Ectothermic – reptiles, amphibians
- do not produce enough metabolic
heat to effect body temperature.
• Need less energy.
http://www.kidzone.ws/animals/polar_bear_2.jpg
• Amount of energy needed to
maintain homeostasis inversely
proportionate (per gram) to size.
• Each gram of a mouse consumes
more energy than elephant.
• Smaller animal – higher metabolic
rate to deliver oxygen, energy.
http://jan.ucc.nau.edu/~sll/images/Elephant-mouse.jpg
• Metabolic rate of nongrowing
endotherm at rest, with empty
stomach, experiencing no stress basal metabolic rate (BMR)
• Metabolic rate of resting, fasting,
nonstressed ectotherm - standard
metabolic rate (SMR).
http://biology.unm.edu/jhbrown/Images/ScalingGraph.GIF
• Behavior above BMR or SMR
consumes energy.
• Maximal BMR determines amount of
energy expended.
• Ectotherms cannot do long, intense
activity.
• BMR of human much higher than
SMR of alligator.
• Factors influence BMR - age, sex,
size, body and environmental
temperatures, quality and quantity
of food, activity level, oxygen
availability, hormonal balance, time
of day.
• How energy used varies among
species.
• Endotherms need more energy;
smaller animals need more energy.
• Human female spends large fraction of
energy budget for BMR, relatively little
for activity and temperature regulation.
• Male penguin spends larger fraction of
energy expenditures for activity - must
swim to catch food.