Transcript An Introduction to Animal Structure and Function

Basic Principles of Animal
Form and Function
Levels of Structural Organization
Body plan and External Environment
Regulating the Internal Environment
Levels of Structural
Organization
• Hierarchy of multicellular organisms
• Celltissueorganorgan system
Organ Systems
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Integumentary
Skeletal
Muscular
Digestive
Nervous
Circulatory
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Respiratory
Immune/Lymphatic
Excretory
Endocrine
Reproductive
Tissue
Groups of cells with common structure and
Function, four types:
• Epithelial
• Connective
• Nervous
• Muscle
Epithelial Tissue
• Tightly packed
• Lines organs and body cavities, covers the
body
• Classified by shape and by number of
layers
Connective Tissue
• Characterized by a sparse cell population
scattered through an extensive
extracellular matrix
• Major types: loose connective, adipose,
fibrous connective, cartilage, bone, blood
Nervous Tissue
• Senses stimuli and transmits signals from
one part of the animal to another
• Neurons – nerve cells
Muscle Tissue
• Consists of long excitable cells capable of
contraction
• Most abundant tissue in animals
• Three types: skeletal, smooth, and
cardiac
Regulating the Internal
Environment
• Interstitial fluid-composed of fluid between
the cells of vertebrates
• Homeostasis-dynamic state of equilibrium
in which internal conditions remain
relatively stable; “steady state”
Thermoregulation
• Adjust rate of exchange between animal and it’s
environment
• vasodilation
• vasoconstriction
• countercurrent heat exchange
• evaporative heat loss
• behavioral responses
• rate of metabolic heat production
Regulation of Body Temperature
• Heat gain or loss in organisms results from:
conduction, convection, radiation, and
evaporation
• Ectotherms: absorb heat from the environment,
most invertebrates, fishes, reptiles, and
amphibians
• Endotherms: derives most of their heat from
metabolism, mammals, birds, some fish, and
numerous insects
Ectothermy
• Body orientation to the sun (locust)
• social organization (honeybees)
Endothermy
• Ability to regulate metabolism
• Humans and other terrestrial mammals
utilize hypothalamus
• Feedback through nervous system results
in vasodilation or vasoconstriction to skin
vessels
Counter Current Heat Exchange
Heat Shock Proteins
• Found in animal cells, yeast, and bacteria
• cells are able to make RAPID adjustments
to temperature changes
• prevent denaturation
• produced by heat-shock genes
Torpor during Environmental
Extremes
• Hibernation
• Estivation
• Daily torpor (diurnal vs nocturnal)