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18/04/12 Animal Systems Organization
& Functions
BIOL212
Overview: Diverse Forms, Common Challenges •  Anatomy is the study of the biological form of an organism •  Physiology is the study of the biological funcDons an organism performs •  The comparaDve study of animals reveals that form and funcDon are closely correlated © 2011 Pearson Education, Inc.
Figure 40.1
1 18/04/12 Concept 40.1: Animal form and funcDon are correlated at all levels of organizaDon •  Size and shape affect the way an animal interacts with its environment •  Many different animal body plans have evolved and are determined by the genome © 2011 Pearson Education, Inc.
EvoluDon of Animal Size and Shape •  Physical laws constrain strength, diffusion, movement, and heat exchange •  As animals increase in size, their skeletons must be proporDonately larger to support their mass •  EvoluDonary convergence reflects different species adaptaDons to a similar environmental challenge Video: Shark EaDng Seal Video: Galápagos Sea Lion © 2011 Pearson Education, Inc.
Figure 40.2
Seal
Penguin
Tuna
2 18/04/12 Exchange with the Environment •  Materials such as nutrients, waste products, and gases must be exchanged across the cell membranes of animal cells •  Rate of exchange is proporDonal to a cell’s surface area while amount of exchange material is proporDonal to a cell’s volume Video: Hydra EaDng Daphnia © 2011 Pearson Education, Inc.
•  A single-­‐celled proDst living in water has a sufficient surface area of plasma membrane to service its enDre volume of cytoplasm •  MulDcellular organisms with a saclike body plan have body walls that are only two cells thick, facilitaDng diffusion of materials © 2011 Pearson Education, Inc.
Figure 40.3
Mouth
Gastrovascular
cavity
Exchange
Exchange
Exchange
0.1 mm
1 mm
(a) Single cell
(b) Two layers of cells
3 18/04/12 •  In flat animals such as tapeworms, the distance between cells and the environment is minimized •  More complex organisms have highly folded internal surfaces for exchanging materials © 2011 Pearson Education, Inc.
Figure 40.4
External environment
CO2 O
Food
2
Mouth
Heart
Digestive
system
250 µm
Lung tissue (SEM)
Cells
Interstitial
fluid
Circulatory
system
Nutrients
Excretory
system
100 µm
Lining of small
intestine (SEM)
Respiratory
system
od
Anus
Unabsorbed
matter (feces)
Metabolic waste products
(nitrogenous waste)
Blood vessels in
kidney (SEM)
50 µm
Blo
Animal
body
Figure 40.4a
External
environment
Mouth
CO2
Food
O2
Blo
Animal
body
Respiratory
system
od
Heart
Digestive
system
Nutrients
Cells
Interstitial
fluid
Circulatory
system
Excretory
system
Anus
Unabsorbed
matter (feces)
Metabolic waste products
(nitrogenous waste)
4 18/04/12 Fjords increase shoreline: Milford Sound, New Zealand Lining of small
intestine (SEM)
100 µm
Figure 40.4b
5 18/04/12 250 µm
Figure 40.4c
Lung tissue (SEM)
Blood vessels in
kidney (SEM)
50 µm
Figure 40.4d
•  In vertebrates, the space between cells is filled with inters11al fluid, which allows for the movement of material into and out of cells •  A complex body plan helps an animal living in a variable environment to maintain a relaDvely stable internal environment © 2011 Pearson Education, Inc.
6 18/04/12 Hierarchical OrganizaDon of Body Plans •  Most animals are composed of specialized cells organized into 1ssues that have different funcDons •  Tissues make up organs, which together make up organ systems •  Some organs, such as the pancreas, belong to more than one organ system © 2011 Pearson Education, Inc.
Heirarchy • 
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Subatomic parDcles Atoms Molecules Organelles Cells Tissues Organs Organ Systems Organism PopulaDon Community Ecosystems The Biosphere Table 40.1
7 18/04/12 Exploring Structure and Function in Animal Tissues
•  Different Dssues have different structures that are suited to their funcDons •  Tissues are classified into four main categories: epithelial, connecDve, muscle, and nervous © 2011 Pearson Education, Inc.
Epithelial Tissue
•  Epithelial 1ssue covers the outside of the body and lines the organs and caviDes within the body •  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 Dles) © 2011 Pearson Education, Inc.
•  The arrangement of epithelial cells may be simple (single cell layer), straDfied (mulDple Ders of cells), or pseudostraDfied (a single layer of cells of varying length) © 2011 Pearson Education, Inc.
8 18/04/12 Figure 40.5aa
Epithelial Tissue
Stratified squamous
epithelium
Cuboidal
epithelium
Simple columnar
epithelium
Simple squamous
epithelium
Pseudostratified
columnar
epithelium
Figure 40.5ab
Apical surface
Basal surface
40 µm
Basal lamina
Polarity of epithelia
Connective Tissue
•  Connec1ve 1ssue mainly binds and supports other Dssues •  It contains sparsely packed cells scagered throughout an extracellular matrix •  The matrix consists of fibers in a liquid, jellylike, or solid foundaDon © 2011 Pearson Education, Inc.
9 18/04/12 •  There are three types of connecDve Dssue fiber, all made of protein: –  Collagenous fibers provide strength and flexibility –  ElasDc fibers stretch and snap back to their original length –  ReDcular fibers join connecDve Dssue to adjacent Dssues © 2011 Pearson Education, Inc.
•  ConnecDve Dssue contains cells, including –  Fibroblasts that secrete the protein of extracellular fibers –  Macrophages that are involved in the immune system © 2011 Pearson Education, Inc.
•  In vertebrates, the fibers and foundaDon combine to form six major types of connecDve Dssue: –  Loose connecDve Dssue binds epithelia to underlying Dssues and holds organs in place –  Car1lage is a strong and flexible support material –  Fibrous connecDve Dssue is found in tendons, which agach muscles to bones, and ligaments, which connect bones at joints © 2011 Pearson Education, Inc.
10 18/04/12 –  Adipose 1ssue stores fat for insulaDon and fuel –  Blood is composed of blood cells and cell fragments in blood plasma –  Bone is mineralized and forms the skeleton © 2011 Pearson Education, Inc.
Figure 40.5ba
Connective Tissue
Loose connective tissue
Blood
Collagenous fiber
Plasma
55 µm
120 µm
White
blood cells
Elastic fiber
Red blood cells
Cartilage
Fibrous connective tissue
30 µm
100 µm
Chondrocytes
Chondroitin sulfate
Bone
Adipose tissue
700 µm
Central
canal
Osteon
Fat droplets
150 µm
Nuclei
Figure 40.5bb
Loose connective tissue
120 µm
Collagenous fiber
Elastic fiber
11 18/04/12 Figure 40.5bc
30 µm
Fibrous connective tissue
Nuclei
Figure 40.5bd
Bone
700 µm
Central
canal
Osteon
Figure 40.5be
Adipose tissue
150 µm
Fat droplets
12 18/04/12 Figure 40.5bf
Cartilage
100 µm
Chondrocytes
Chondroitin sulfate
Figure 40.5bg
Blood
Plasma
55 µm
White
blood cells
Red blood cells
Muscle Tissue
•  Muscle 1ssue consists of long cells called muscle fibers, which contract in response to nerve signals © 2011 Pearson Education, Inc.
13 18/04/12 •  It is divided in the vertebrate body into three types: –  Skeletal muscle, or striated muscle, is responsible for voluntary movement –  Smooth muscle is responsible for involuntary body acDviDes –  Cardiac muscle is responsible for contracDon of the heart © 2011 Pearson Education, Inc.
Figure 40.5ca
Muscle Tissue
Skeletal muscle
Nuclei
Muscle
fiber
Sarcomere
100 µm
Smooth muscle
Nucleus
Muscle fibers
Cardiac muscle
25 µm
Nucleus
Intercalated disk
50 µm
Figure 40.5cb
Skeletal muscle
Nuclei
Muscle
fiber
Sarcomere
100 µm
14 18/04/12 Figure 40.5cc
Smooth muscle
Nucleus
Muscle fibers
25 µm
Figure 40.5cd
Cardiac muscle
Nucleus
Intercalated disk
50 µm
Nervous Tissue
•  Nervous 1ssue senses sDmuli and transmits signals throughout the animal •  Nervous Dssue contains –  Neurons, or nerve cells, that transmit nerve impulses –  Glial cells, or glia, that help nourish, insulate, and replenish neurons © 2011 Pearson Education, Inc.
15 18/04/12 Figure 40.5da
Nervous Tissue
Neurons
Glia
Glia
15 µm
Neuron:
Dendrites
Cell body
Axons of
neurons
40 µm
Axon
Blood
vessel
(Fluorescent LM)
(Confocal LM)
Figure 40.5db
Figure 40.5dc
16 18/04/12 CoordinaDon and Control •  Control and coordinaDon within a body depend on the endocrine system and the nervous system •  The endocrine system transmits chemical signals called hormones to recepDve cells throughout the body via blood •  A hormone may affect one or more regions throughout the body •  Hormones are relaDvely slow acDng, but can have long-­‐lasDng effects © 2011 Pearson Education, Inc.
Figure 40.6
Figure 40.6a
17 18/04/12 •  The nervous system transmits informaDon between specific locaDons •  The informaDon conveyed depends on a signal s pathway, not the type of signal •  Nerve signal transmission is very fast •  Nerve impulses can be received by neurons, muscle cells, endocrine cells, and exocrine cells © 2011 Pearson Education, Inc.
Figure 40.6b
Concept 40.2: Feedback control maintains the internal environment in many animals •  Animals manage their internal environment by regulaDng or conforming to the external environment © 2011 Pearson Education, Inc.
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