5.1

tissue

group of similar cells and cell products that arise from the same region of the embryo and work together to perform a specific structural or physiological role in an organ

matrix

extracellular material that surrounds the cells, composed of fibrous proteins and ground substance

ground substance

clear gel that contains water, gases, minerals, nutrients, wastes, hormones, and other chemicals

in cartilage and bone, the matrix is…

a rubbery or stony material

epithelial tissue

composed of layers of closely spaced cells that covers organ surfaces; forms glands; and serves for protection, secretion, and absorption

epithelial tissue is located in the…

epidermis, inner lining of the digestive tract, liver, and other glands

connective tissue

typically has more matrix than cells volume, often specialized to support and protect organs, and to bind other tissues and organs to each other

connective tissue is located in the…

tendons, ligaments, cartilage, bone, and blood

nervous tissue

contains excitable cells and is specialized for rapid transmission of coded information to other cells

nervous tissue is located in the…

brain, spinal cord, and nerves

muscular tissue

composed of elongated, excitable muscle cells and is specialized for contraction

muscular tissue is located in the…

skeletal muscles, heart, and walls of viscera

the primary germ layers originate from…

a single cell, which becomes a fertilized egg, which becomes identical, smaller cells, which become the primary germ layers

primary germ layers

three layers that give rise to all the body’s mature tissues

the primary germ layers are the…

ectoderm, endoderm, and mesoderm

ectoderm

outer primary germ layer that gives rise to the epidermis and nervous system

endoderm

inner primary germ layer that gives rise to the mucous membranes of the digestive and respiratory tracts, digestive glands, and more

mesoderm

primary germ layer of more loosely organized cells that eventually turns into mesenchyme and gives rise to cardiac muscle, bone, blood, and other tissues

histological section

thin tissue slice mounted on a microscope slide

fixative

chemical that prevents decay

stain

artificial color meant to enhance detail

longitudinal section

tissue cut on its long axis

cross section

tissue cut perpendicular to a longitudinal section

oblique section

tissue cut on a slant between a longitudinal and cross section

smear

liquid tissue rubbed or spread across the slide

spread

membrane or cobwebby tissue laid out on a slide