BIOLOGY 1A Lecture Notes - Lecture 30: Nervous Tissue, Muscle Tissue, Blood Vessel
ANIMAL FORM AND FUNCTION
Levels of Organization
Three key principles of physiology
Form=anatomy
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Function= Contribution to survival of organisms
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Regulation= Control and coordination of body systems
A key goal of physiology is to determine the relationships
between these 3 principles
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Levels of Organization: Cell--> Tissue--> Organ--> Organ System
Cell: cellular processes specialized to perform the tasks required of
a given physiological system
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Tissue: collections of cells that perform similar functions that are
held together by extracellular material and cell-cell junctions
4 types: Connective, epithelial, muscle, nervous
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Muscle tissue form and function: 3 types
Skeletal: STRIATED; under voluntary control and moves
the skeleton
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Smooth: form walls of organ and surround blood vessel
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Cardiac: found in the heart
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Nervous tissue: comprised of two types of cells- neurons and
glia
Function:
Sensory input
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Control of muscles and glands
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Homeostasis
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Mental activity
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Connective tissue:
Mainly binds and supports other tissues
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Contains sparsely packed cells scattered throughout an
extracellular matrix consisting of fibers, made of
proteins
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Contains cells, including fibroblasts and macrophages
Examples: tendons, ligaments, bone, adipose,
blood and cartilage
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Ex. collagen fibers linking fibroblasts together
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Epithelial tissue: covers the outside of the body and lines the
organ and cavities within the body
Contains cells that are closely joined- forming a barrier
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POLARIZED- apical surface faces lumen and is exposed
to air or fluid
Apical is different than basal surface
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Lumen is inside of the canal
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Regulates exchange of materials; single layer
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Organ: 2 or more primary tissues organized to form a function
5 vital: brain, heart, liver, lungs, kidney□
Gut: □
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Organ Systems: collection of organs that perform related functions
essential to survival
11: Nervous, muscular, endocrine, circulatory, excretory,
digestive, respiratory, immune, skeletal, integumentary,
reproductive
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I.
Exchange Surfaces
Food through mouth, absorbed, then feces
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Absorb oxygen through respiratory system then distribute through
circulatory
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Exchange surfaces are internal yet connected to the outside environment
Lining of small intestine, Lung tissue, Blood vessels in the kidney
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Exchange surfaces are highly branched to maximize surface area
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Fluid compartments in the body- exchange across cells
Blood contains nutrients; need to go to cells; they pass into
interstitial fluid then into the cell
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Body fluid: 10 gallons
Intracellular fluid: 66%□
Interstitial: 25% EXTRACELLULAR□
Blood: 8%. EXTRACELLULAR□
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Intracellular fluid= water + dissolved ions inside of cells= cytosol
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Extracellular fluid= interstitial fluid + blood
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II.
Regulation and Control
Endocrine system: transmits chemical signals called hormones to
receptive cells throughout the body via blood
Many targets, depend on presence of receptors
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Hormones are relatively slow acting, but can have long-lasting
effects
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Nervous system: transmits information between specific locations
Target depends on signal's pathway
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Nerve signal transmission is very FAST
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Coordination and Control often act to maintain homeostasis
Cell function requires that internal body conditions be relatively
constant
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Homeostasis= ability of body to maintain steady state of
physiological conditions
Ex. body temp, blood pH and glucose concentration□
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Control systems: Negative vs. Positive feedback loops
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Endothermy and ectothermy- source of heat for thermoregulation
Endothermic= generate heat by metabolism
Birds and mammals□
Active at a greater range of external temperatures□
Usually but not always at a constant body temperature
Ex. hibernation
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Ectothermic= gain heat from external sources
Most invertebrates, fishes, amphibians and non-avian reptiles□
Tolerate greater variation in internal temperate□
But, fish and lizard body temp stays constant□
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1.
Variations in body temperature with environment: regulators vs.
conformers
River otter is an endotherm and their body temperature stays
constant
i.
The fish adjusts to the temperature in the environment ii.
2.
5 adaptations help animals thermoregulate:
Insulation (hair, blubber)
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Evaporative heat loss (sweating, panting)
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Behavioral responses
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Circulatory adaptations
Countercurrent exchange helps minimize heat loss
A duck has its feet in cold water; the fins of dolphin are
in cold water
Arteries carrying blood to feet and veins carrying
it back are close together so that the blood heats
up the vein so its not cold when it gets back to
center of body
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Adjusting metabolic heat production
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In humans, the temperature sensor is in the hypothalamus
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III.
Lecture 30-4/9
Tuesday, April 10, 2018
8:39 PM
Document Summary
A key goal of physiology is to determine the relationships between these 3 principles. Levels of organization: cell--> tissue--> organ--> organ system. Cell: cellular processes specialized to perform the tasks required of a given physiological system. Tissue: collections of cells that perform similar functions that are held together by extracellular material and cell-cell junctions. Skeletal: striated; under voluntary control and moves the skeleton. Smooth: form walls of organ and surround blood vessel. Nervous tissue: comprised of two types of cells- neurons and glia. Contains sparsely packed cells scattered throughout an extracellular matrix consisting of fibers, made of proteins proteins. Examples: tendons, ligaments, bone, adipose, blood and cartilage. Epithelial tissue: covers the outside of the body and lines the organ and cavities within the body. Contains cells that are closely joined- forming a barrier. Polarized- apical surface faces lumen and is exposed to air or fluid. Organ: 2 or more primary tissues organized to form a function.
