Download Animals: The Animal Body

The Animal Body
Chapter 37
Tissues: Epithelial
 Cells fit tightly together to form a sheet
 One side is exposed on the surface of the body or the
lining of a cavity
 Functions: protection, absorption, secretion, sensation
 Three types of cells classified by shape:
 Squamous – thin, flat
 Cuboidal – short, cube-shaped
 Columnar – column-shaped
 Number of layers:
 Simple epithelium – one layer of cells; in areas of
secretion or absorption
 Stratified epithelium – 2 or more layers; involved in
protection
Tissues: Epithelial…
 Glands – one or more epithelial cells
specialized to produce and secrete
sweat, milk, mucus, wax, saliva,
hormones, or enzymes
 Types:
 Exocrine – secrete products onto free
epithelial surface usually through a duct
 Endocrine – no ducts; release products
(hormones) into interstitial fluid
Tissues: Connective
 Supports and cushions organs
 Few cells embedded in intercellular
substance - fibers scattered through a
matrix
 Three types of fibers:
 Collagen – made of collagens; the most
numerous; very tough
 Elastic – made of elastin; form networks; can
return to their original shape
 Reticular – collagen and some glycoprotein;
thin, branched fibers; thin and join connective
tissue to other tissues
Types of Connective Tissue
 Loose –attaches skin to muscles and
lower structures
 Dense – found in the lower dermis
 Tendons – connect muscles to bones
 Ligaments – connect bones to bones
 Elastic – in lungs and walls of
arteries
 Reticular – internal supporting
network for many organs
Types of Connective Tissue…
 Adipose – stores fat; below skin and in
tissue that cushions internal organs
 Cartilage – firm yet flexible; provides
shape of some organs and cushions joints
 Bone – main framework in vertebrates;
also involved in blood cell production
 Blood and lymph – specialized cells that
help body parts communicate
 Muscle – allow movement
 Skeletal – attached to bones
 Cardiac – found in heart
 Smooth – wall of internal organs
Tissues: Nervous
 Neurons – specialized for receiving
and transmitting signal
 Cell body – main cell with two types of
extensions:
 Dendrites – carry info to the cell
 Axons – carry info away from the cell
Organs and Organ Systems
 Integumentary – covers and protects
 Skin, hair, nails, sweat glands
 Skeletal – supports and protects
 Bones, cartilage, ligaments
 Muscular – provides locomotion
 Skeletal, smooth, and cardiac muscles
 Digestive – ingests and digests food
 Mouth, esophagus, stomach, intestines, liver,
pancreas, salivary glands
 Circulatory – transports materials
throughout body
 Heart, blood vessels, blood, lymph, lymph nodes
Organs and Organ Systems…
 Respiratory – gas exchange
 Lungs, trachea
 Urinary – excretion of metabolic wastes
 Kidney, bladder, ducts
 Nervous – receives and responses to stimuli;
coordinates other systems
 Brain, nerves, sense organs, spinal cord
 Endocrine – regulates body chemistry and
function
 Ductless glands (pituitary, adrenal, thyroid)
 Reproductive – sexual reproduction
 Testes, ovaries, uterus
Thermoregulation
 Body heat is produced as a by-product of metabolic
activity
 Ectotherms – use the heat of their environment to
supplement body heat
 Require less food; cannot survive in all climates
 Endotherms – supply heat from food to maintain body
temperature
 Require additional food; can live in more places
 Acclimation – adjusting to seasonal changes in
environmental temperatures (ex: dog growing thicker
coat in winter)
 Dormancy – a strategy to survive seasonal cold or
heat
 Hibernation
 Estivation