The Animal Body: Four Tissue Types Flashcards
what are tissues
collections of cells and cell products that perform specific, limited functions
what is histology the study of
tissues
what are the four types of tissues
epithelial, connective, muscle, neural
epithelial
covers/lining the inside and outside
connective
connect
muscle
contract
neural
communicates
epithelial tissue
covers body surfaces
lines cavities
line tubular structures
serves essential functions
functions of epithelial tissues
provide physical protection
control permeability(ability to let things go through or not)
provide sensation
produce specialized secretions(glandular epithelium)
-exocrine glands
-endocrine glands
classifications of epithelial tissues
combines a cell shape with the number of layers of cells
classification is based on layers
simple epithelium
stratified epithelium
simple epithelium
single layer of cells
stratified epithelium
several layers of cells
classification is based on shape
squamous epithelia, cuboidal epithelia,
columnar epithelia
squamous epithelia
thin and flat
cuboidal epithelia
square shaped
columnar epithelia
tall, slender rectangles
epithelia are replaced by mitosis
cell division of stem cells or germinative cells
what are stem cells
they are unspecialized cells that can give rise to types of functional cells
types of stem cells
unipotent, oligopotent, multipotent, totipotent
unipotent
one kind
oligopotent
few kind
multipotent
many kind
totipotent
any type/totally
endocrine glands(inside)
release hormones
- into interstitial fluids and plasma
- no ducts
exocrine glands(outside)
produce secretions
- onto epithelial surfaces
- through ducts
what is a connective tissue
it provides a protective structural framework for other tissue types
what are the three basic components of connective tissues
specialized cells, solid extracellular protein fiber, fluid extracellular ground substance
characteristics of connective tissue
the extracellular components of connective tissues(fibers and ground substance) make up the matrix
- majority of tissue volume
- determines specialized function
functions of connective tissue
support and protections
transportation of materials
storage of energy reserves
defense of the body
three major types of connective tissue
connective tissue proper
fluid connective tissues
supporting connective tissues
cells of connective tissue proper
fibroblasts, macrophages, fat cells(adipocytes)
fibroblasts
most abundant cells in connective tissue proper
produce connective tissue fibers and ground substance
macrophages
scattered throughout the matrix
phagocytize damaged cells or pathogens that enter the tissue
release chemicals that mobilize the immune system
what are the three basic types of connective tissue fibers
collagen fibers, elastic fibers, reticular fibers
what is a collagen fibers
long, straight, unbranched
strong, but flexible
most common
what is a elastic fibers
branched and wavy
after stretching, they will return to their original length
contain the protein elastin
what is a reticular fibers
made of same protein subunits as collagen fibers, but arranged differently
thinner than collagen fibers
forming branching, interwoven frameworks in various organs
least common
ground substance
clear, colorless, viscous
fills spaces between cells and slows pathogen movement
types of connective tissue proper
loose connective tissue, dense connective tissue
loose connective tissue
“packing materials” of the body
more ground substance, fewer fibers
example: fat(adipose tissue)
dense connective tissue
tough, strong, and durable
more fibers, less ground substance
example: tendons
fluid connective tissues
blood and lymph
blood and lymph
watery matrix of dissolved proteins carry specific cell types(formed elements) -formes elements of blood ---red blood cells ---white blood cells ---platelets
supporting connective tissues
cartilage and bone
cartilage
gel-type ground substance
for shock absorption and protection
bone
calcified (made rigid by calcium salts, minerals)
for weight support
chondrocytes(cartilage cells)
surrounded by lacunae(chambers)
avascular
chondrocytes in lacunae
perichondrium
outer, fibrous layer(for strength)
inner, cellular layer(for growth and maintenance)
three major types of cartilage
hyaline cartilage, elastic cartilage, fibrocartilage
hyaline cartilage
stiff, flexible support
reduces friction between bones
found insynovial joints, rib tips, sternum, and trachea
elastic cartilage
supportive but bends easily
found in external ear and epiglottis
fibrocartilage
limits movement
prevent bone-to-bone contact
pads knee joints
found between pubic bones and intervertebral discs
bone also called osseous tissue
strong(hard calcium compounds) resistes shattering(flexible collagen fibers)
bone cells or osteocytes
arranged around central canals within matrix
found inside lacunae as with cartilage
small channels through matrix(canaliculi) access blood supply
tissue membranes
are physical barriers
line or cover portions of the body
what do tissue membrane consist of
an epithelial layer
supporting connective tissues
four types of tissue membranes
mucous, serous, cutaneous, and synovial membranes
mucous membranes
are cotes with secretions of mucous glands. these membranes line the digestive, respiratory, urinary, and reproductive tracts
serous membranes
line the ventral body cavities (the peritoneal, pleural, and pericardial cavities)
cutaneous membrane or skin
covers the outer surface of the body
synovial membranes
line joint cavities and produce the fluid within the joint
three types of muscle tissue
skeletal muscle, cardiac muscle, and smooth muscle tissue
skeletal muscle tissue
large body muscles responsible for movement
cardiac muscle tissue
found only in the heart
smooth muscle tissue
found in walls of blood vessels
found around hollow organs such as the urinary bladder
around the respiratory, digestive, and reproductive tracts
functions of muscle tissue
specialized for contraction
produces all body movement
neural tissue also called nervous or nerve tissue
specialized for conducting electrical impulses
rapidly senses internal or external environment
processes information and control responses
neural tissue concentrated in the central nervous system
brain
spinal cord
two kinds of neural cells
nerons and neuroglia
what is a neurons
nerve cells
perform electrical communication
what is neuroglia
supporting cells
repair and supple nutrients to neurons
what are the cell parts of a neuron
cell body, dendrites, axon(nerve fiber)
cell body
contains the nucleus and nucleolus
dendrites
short branches extending from the cell body
receive incoming signals
axon(nerve fiber)
long, thin extension of the cell body
carries outgoing electrical signals to their destination
tissues respond to injuries to maintain homeostasis
cells restore homeostasis with two processes
- inflammation
- regeneration
inflammatory response
the tissue’s first response to injury
signs and symptoms of inflammation includes:
swelling
heat
redness
pain
inflammatory response can be triggered by:
trauma(physical injury)
infection(the presence of harmful pathogens)
aging tissue with age
rate of tissue repair declines
cancer rates increase
speed and efficiency of tissue repair decrease with age due to:
slower rate of energy consumption(metabolism)
