Lab 4 Flashcards
Tissue
A group of similar cells and their intercellular matrix, united by a common function
Neurons
Large cells with one or more processes, or projections (dendrites and axons), extending from the cell body; function to conduct nerve impulses
Dendrites
Carry nerve impulses toward the neuron cell body
Axons
Carry nerve impulses away from the cell body
Neuroglia
Small cells surrounding neurons; function to support and protect neurons
Multipolar neurons
Have one axon and 2 or more dendrites; they are located in the brain and spinal cord and function to send nerve impulses to skeletal muscles
Bipolar neurons
Have be axon and one dendrite; associated with in the special sense of vision, hearing, and smell and function to relay sensory information to the brain
Unipolar neurons
Have a single process from the nerve cell body which joins a continuous axon and dendrite; function as the body’s internal sensors
Epithelium
Tissue that covers the body or lines internal cavities
Simple epithelium
When epithelium is one cell layer thick
Stratified epithelium
When epithelium has more than one layer of cells
Cuboidal epithelial cells
Shaped like a cube, and are about as wide as they are high
Squamous epithelial cells
Flat, scale-like cells
Columnar epithelial cells
Shaped like columns, and are higher than they are wide
Simple squamous epithelium
Consists of a single layer of flattened, pancake-like cells next to a space, or lumen
Simple cuboidal epithelium
Consists of a single layer of cube-shaped cells
Simple columnar epithelium
Consists of a single layer of column-shaped cells
Stratified squamous epithelium
Possesses multiple layers of cells; the cells next to the base membrane are either cuboidal or columnar, and progressively flatten into squamous cells as they near the surface of the lumen
Stratified cuboidal epithelium
Consists of multiple layers of cube-shaped cells
Stratified columnar epithelium
Consists of multiple layers of columnar shaped cells; some have cilia which project into the lumen of the body structure
Pseudostratified epithelium
Looks similar to stratified epithelium; the nuclei appear in many levels and some cells appear to rest upon other cells, however, if the tissue is carefully examined, one can see all of the cells in contact with the basement membrane
Transitional epithelium
Consists of between two to about six layers of cells; the cells in the basal portion of the tissue are essential cuboidal, the cells near the apical surface are flattened, but not as flat as squamous
Muscle tissue
Occurs in sheets of bundles
Muscle
Create movement by contracting or shortening along their length
Cardiac muscle
One of the two types of muscle tissue which exhibits striation, the striation are perpendicular to the long axis of the muscle cells
Cardiac muscle cells
Relatively long and branched within the sheet; joined end to end by intercalated discs and appear as single, relatively thick, dark bands perpendicular to the long axis, or length, of the cell
Skeletal muscle tissue
Other type of muscle tissue that is striated; the striations appear as light and dark bands perpendicular to the long axis cell
Skeletal muscle cell
Large, rod-like cells that lay in relatively parallel sheets
Smooth muscle
NOT striated; primarily occurs in the walls of tubes or internal passageways
Smooth muscle cells
Spindle-shaped, thick in the middle and tapered at each end; each has a single nucleus located in its center
Connective tissue
Most abundant, widely distributed, and varied; the cells in connective tissue are haphazardly arranged and usually occupy less space than the intercellular matrix
Three categories of connective tissues
Distinctive, cartilage and less distinctive
Adipose tissue
Distinctive because the cells tend to be rather and globular in shape
Adipose cell
Filled with a fat droplet which pushes the nucleus and cytoplasm of the cell p against the cell membrane
Blood cells
Easily recognized because they are small, oval, and usually stained red; in mammals, cells lack a nucleus and resemble smal doughnuts
Compact bone
Perhaps most distinctive of all connective tissues; contains structural units called “osteons” that are composed of layers that look like rings one cross section of stumps
Cartilage
Supportive tissue like bone; much more flexible; contains a stiff matrix of collagen fibers and the cells are located on small cavities “lacunae”
Hyaline cartilage
Has translucent, glossy appearance which is relatively evenly colored when stained; the nucleated cells in the lacunae will be randomly dispersed throughout the tissue; colored, baby Swiss cheese
Elastic cartilage
Similar to hyaline cartilage; contains darkly stained fibers which radiate in all directions from the cells in the lacunae; looks like moldy, baby Swiss cheese
Fibrocartilage
Appears similar to hyaline cartilage; contains fibers in layers which run relatively parallel to each other; it looks “stringy”
Reticular connective tissue
Has small, darkly stained fells surrounded by root-like fibers in a matrix with considerable space between the cells; has sponge-like appearance; small pores of a sponge
Dense regular connective tissue
Has layers closely packed collagen fibers running in one direction; looks like smooth muscle, but has few cells and therefore few nuclei
Dense irregular connective tissue
Has thick bundles of collagen fibers and few cells but collagen fibers run in random directions
Areolar connective tissue
Have lots of empty space between the haphazardly arranged cells; long, thin fibers run in random directions; fibers look like cotton that has been pulled apart
