4 main types of tissues
epithelial
connective
muscle
nerve
epithelial
lines surface
connective
joins other tissue types together
muscle
contracts and relaxes
involved in movement
nerve
generates and conducts nerve impulses
epithelium
a layer of closely packed cells that lines an external or internal surface
has no blood supply; it is nourished by diffusion from the blood supply of he connective tissue adjacent to it
chief function is protection but also secretion, absorption secretion, excretion, lubrication, and even sensory perception
TYPES OF EPITHELIAL
simple epithelium
stratified epithelium
simple epithelium
single layer
squamous cells that are flat in shape: intestinal serosa
cuboidal (cells are cubical): thyroid follicles
columnar (cells are long and narrow): intestinal mucosa
simple squamous epithelium
composed of cells shaped like tiles thin and flat with round or oval nuclei.
specialized for exchange of materials.
lines inside walls of blood vessels body cavity and the bowman capsules of the kidney
simple cuboidal epithelium
appear square in side view and have a secretory or absorptive function.
found in areas such as kidney tubules and thyroid follicles
simple columnar epithelium
composed of cells that are significantly taller than they are wide
appear as a row of rectangles standing on end, with the nuclei frequently all at the same level, usually in the lower part of the cell
may be ciliated
golblet cells specialized for the secretion of mucus
found where a need for secretion or absorption exists and the wear and tear is considerable. lines a large part of respiratory and digestive tracts and oviducts
stratified epithelium
composed of two or more layers of epithelial cells. it is not adapted for absorption or secretion but for areas subject to extensive wear and tear.
forms outer layer of skin mouth esophagus, anus, vagina,
pseudo stratified columnar epithelium
simple epithelium with all the cells resting on a basement membrane
cells have the appearance of a stratified epithelium because they are not all the same height and their nuclei are located at different levels.
lines trachea bronchi male urethra
stratified epithelium
2 or more layers thick
human skin
types of connective
adipose
cartilage
bone
blood
dermis
loose connective tissue (areolar, reticular, adipose)
serves as packing material filling spaces between body parts
dense connective tissue (dermis fasciae, ligaments, and tendons)
perform major supportive function
blood
derived from a form of loose connective tissue and cartilage and bone
fibers
collagenous
elastic
reticular
collagenous fibers
appear as thick wavy bundles of finer fibrils. They are flexible but very strong and resistant to stretching
elastic fibers
thin branching threads that usually appear straight
reticular fibers
consist of bundles of small inelastic fibrils.
smaller than collagenous fibers and they branch and reunite extensively
adipose connective tissue
fat
catilage
most common form is hyaline cartilage
found on the ends of long bones and in the nose trachea
matrix is firm and flexible
lacunae- cavities containing one cell
bone
most specialized
bone matrix secreted by bone forming ells called osteocytes and is composed of crystals of calcium phosphate with collagenous fibers between the crystals to reduce the brittleness of the bone
compact bone and spongy bone
periosteum
thin layer of dense connective tissue that covers bone
enthrocytes
red blood cells
leukocytes
white blood cells
granular leukocytes
neutrophils
eosinophils
basophils
neutrophils
finely granular cytoplasm and a polymorphic nucleus with from three to five lobes
MOST ACTIVE PHAGOCYTE
eosinophils
bilobed nucleus which amy be partly obscured by bright red spherical granules in the cytoplasm
basopils
have an elongate curved nucleus which may be partly obscured by blue granules in the cytoplasm
agranular leukocytes
lymphocyetes
monocytes
lymphocytes
slightly larger than enthrocytes
have nucleus which is only slightly smaller than the cell itself.
cytoplasm forms thin clear cresent around the cells nucleus
monocytes
larger and have a smaller nucleus more cytoplasm visible
MOST ACTIVE PHAGOCYTE
blood platelets
disk shaped fragille clot promoting bodies found only in mammal blood
smooth muscle
simplist
digestive tract uterus
skeletal muscle
long cylindrical blunt ends
have blood vessels and nerves
tongue
cardiac muscle
heart
have intercalated discs which mark the boundaries between the ends of adjacent cells
nerve tissue
nerve cells called neurons
neuron
carry impulses into the nerve cell called dendrites
those that carry impulses away are called axons
in what ways does epithelial tissue differ from other tissue types
it has specialized types and is used for absorption, secretion, excretion, lubrication, and sensory perception
in what important way does connective tissue differ from other tissue types
connects tissues together provides structure and support and function in metabolism. it is largely composed of extracellular matrix
compare and contrast cartilage and bone
bone is specialized in structural support
cart is found at the end of bones in the nose trachea providing cushioning support
both are connective tissues
compare and contrast the structures of the three muscle types
skeletal: made of fibers bundles and found in connective muscle tissues; richly supplied by blood vessels and nerves
smoothL found in digestive tract uterus; sustained areas that contract used for involuntary action
cardiac: found in heart; involuntary slow rhythmic contractions
parts of neuron
neuron consists of a cell body dendrites axons and mycelian sheath (supportive cell membrane)
how does a tissue differ from an organ
group of cells specialized for a particular function is a tissue while an organ is a group of tissues
all tissue types in small intestine
mucosa, submucosa, smooth muscle, goblet cells
tissues found in c.s of the small intestine from the outside to the lumen
subucosa, smooth tissue, serosa, mucosa, longitudinal muscle, lumen
tissue in hamburger in order of abundance
skeletal- support
connective-fats
peripheral nerve tissue- throughout body of cow
bone and cartilage