Download notes Ch. 40 tissues

Chapter 40 ~An Introduction to
Animal Structure and Function
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I. Tissues: groups of cells with a common
structure and function (4 types)
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A. Connective tissue:
– 1. structure • a. most abundant & widely distributed
• b. Exists in more varied forms than any other
tissue
• c. Form of connective tissue determined by
matrix
–matrix is non-living material between cells
– 2. function –
• a. forms a supporting framework for body as a
whole & individual organs
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3. 3 types
– Collagen fibers (protein)– flexible
– Elastin fibers (protein) rubbery
– Reticular fibers (thin branched collagen
fibers)
4. examples:
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Blood – fluid matrix
Adipose – gel-like & sparse
Bone – most specialized
Cartilage & fibrous
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B- Epithelial tissue:
– 1. structure
• a. held together by tight junctions (very little
matrix)
• b. forms continous sheets that are avascular
– Avascular = no blood vessels (gets
materials through osmosis
– 2. function
• a. protective lining outside of body and
protective lining of organs and cavities
(includes mucus membrane)
• b. identified by shape
3. examples
a. Simple: single layer of cells
b. Stratified: multiple tiers of cells
c. Cuboidal (like dice)
d. Columnar (like bricks on end)
e. Squamous (like floor tiles)
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C.-Nervous tissue: senses stimuli and
transmits signals from 1 part of the animal to
another
– 1. Structure
• A. 3 types of nerve cells- sensory,
motor, assoc.
– 2. function
• A. to receive, interpret, & respond to
stimuli
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D- Muscle tissue: capable of contracting when
stimulated by nerve impulses; myofibrils composed
of proteins actin and myosin; 3 types:
– 1. structure
• A. Large, long cells
• B. 3 types
– 1) striated/skeletal
– 2) smooth – organs, involuntary
– 3) cardiac – heart
II. Organization
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A. levels or organization:
Atom
Molecule
Cell
Tissue
Organ
System
Organism
(population, community)
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Circulatory-internal distribution
Digestive-food processing
Excretory-waste disposal;
osmoregulation
Endocrine-coordination of body
activities
Immune/Lymphatic-defense
Integumentary-protection
Muscular-movement; locomotion
Nervous-receive, interpret, responedto
stimuli
Respiratory-gas exchange
Reproductive-reproduction
Skeletal-support; protection
III. Internal regulation
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A. Interstitial fluid:
internal fluid
environment of
vertebrates; exchanges
nutrients and wastes
B. Homeostasis:
“steady state” or
internal balance
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C. Negative feedback:
– 1. change in a physiological variable that is
being monitored triggers a response that
counteracts (negatively) the initial fluctuation;
2. ex. body temperature
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D. Positive feedback:
– 1. physiological control mechanism in which a
change in some variable triggers mechanisms
that amplify the change (positively)
– 2. ex.uterine contractions at childbirth
IV. Metabolism: sum of all energyrequiring biochemical reactions
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A. terms
– 1. Basal Metabolic Rate (BMR): minimal
rate powering basic functions of life
(endotherms)
– 2. Standard Metabolic Rate (SMR):
minimal rate powering basic functions of
life (ectotherms)
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B. Thermoregulation- maintaining body temp
– 1. Endotherms aka homeotherms: bodies
warmed by metabolic heat
• Body temp constant
– 2. Ectotherms: aka poikliotherms bodies
warmed by environment
• Body temp changes with environment
– 3. regulation of body temp
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3. regulation of body temp
– a. cooling by evaporation
• Sweating
– b. warming by metabolism
• Muscle contraction & other metabolic
activities generate heat
– c. adjusting surface area to regulate temp
• Change vol of blood flow to
extremities
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d. countercurrent exchange – (in cold
environs) warm blood moving to
extremities runs adjacent to cold blood
moving away from extremities – heat
absorbed by cold blood is redistributed to
internal parts of body