Histology Practical Flashcards
(43 cards)
Epithelial Tissue Characteristics:
It lines body cavities and hollow organs Covers the body surface – your skin is a barrier to the outside world Basal is the side of the epithelial cell that is in contact with the connective tissue below, and the apical (top) side is the free side, or the side that is exposed to the hollow space of the organ, cavity, or external surface of skin. Cells readily divide via mitosis to quickly replace damaged or dead cells. It is avascular (no blood vessels) –blood vessels in the underlying connective tissue deliver substances to the epithelial cells. Forms glands
Simple Squamous:
Single layer of “squished” cells yields a very thin barrier Functions in easy passage, diffusion, of substances Found in capillaries and walls of the lung – both places requiring easy and quick exchange of substances
Simple Cuboidal:
Single layer of cube like or wedge-shaped cells Functions in production and secretion of fluids such as sweat and oil. Also functions in reabsorption in the kidneys Found making up many of the glands in the body; also found in the walls of the kidney tubules
Simple Columnar:
Single layer of columnar cells with nuclei aligned in a row; goblet cells are present to produce mucus Can be ciliated or nonciliated; ciliated found in the uterine tubes and nonciliated type lines the digestive tract Functions in providing a protective barrier, allows absorption of material
Pseudostratified Ciliated Columnar:
Single layer of columnar cells with nuclei at different levels so it appears stratified Found in the respiratory tract from the nasal cavity, trachea, down the bronchi Ciliated to move mucus along
Transitional:
Many cells – cuboidal shape near the basement membrane, and mushroom cap-like cells near the apical side. When stretched, the mushroom-cap cells flatten to squamous Functions in stretching as urine collects/passes through the organ Found in the walls of the ureters, urinary bladder, and the proximal urethra (portion right off of the bladder)
Stratified Squamous:
Multiple layers of cells creating a thick membrane. Bottom cells are cuboidal or columnar and divide readily, surface cells are flattened. Can be keratinized or nonkeratinized. Functions in protecting the underlying tissue from abrasion Keratinized type makes up the epidermis of your skin, which is a dry surface. Nonkeratinized type is found in the moist linings of the esophagus, mouth, and the vagina.
Simple Squamous Epithelium
Simple Cuboidal
Simple Columnar
Pseudostratified Ciliated Columnar
Transitional
Stratified Squamous Kerantinized
Stratified Squamous Nonkerantinized
Muscle Tissue Characteristics
Cells have the appearance of a fiber
Muscle cells primary function is contraction, which is achieved by shortening of the muscle fiber by the sliding of protein filaments and overlapping over one another
Skeletal Muscle
Long, cylindrical, striated (banded), parallel cells; many nuclei displaced to the periphery of the cell
Muscle cells (fibers) are attached to bones and are under voluntary (you have conscious control) control to move the skeleton
Found attached to the bones of the skeleton
Skeletal Muscle
Cardiac Muscle:
Cells are branched, striated, with one centrally located nucleus. Intercalated discs are present to join the cells to one another
Muscle cells (fibers) are under involuntary (you have no conscious control) control and allow for the contraction of the heart
Found only in the walls of the heart chambers, hence the name cardiac
Cardiac Muscle
Smooth Muscle:
Cells are spindle-shaped, no striations, with one centrally located nucleus. Smooth muscle is involuntary like cardiac muscle
Found in the hollow organs of the digestive tract, uterine wall, and blood vessels
Muscle cells (fibers) function in propelling food through the digestive tract, uterine contractions during labor, and regulating blood pressure by the contraction and dilation of blood vessels
Smooth Muscle
Connective Tissue Characteristics:
The most abundant tissue type in the body
All types of connective tissue have the same common embryonic origin (arise from same stem cell)– a mesenchyme cell
Unlike the epithelial tissue which includes cells bound to one another in one or many layers to create a barrier, the cells in connective tissue are sparse; therefore the “space” around the cells of connective tissue is actually made up of a material called the matrix.
Matrix consists of ground substance– fills the space between cells, fibers– collagen, elastin, and reticular, and cells– fibroblasts, chondroblasts, osteoblasts, and hematopoietic stem cells, etc.
Many functions: fills spaces, protects against infections, binds structures, produces blood cells, serves as framework, provides support and protection, stores fat, helps repair tissue damage
May be avascular (no blood vessels) i.e., cartilage, or have a high degree of vascularity i.e., bone.
Loose Areolar Connective Tissue:
Composed of a gel-like matrix composed of all three types of fibers; collagen, elastin, & reticular. Cells present are fibroblasts, macrophages and other white blood cells.
Function is to wrap and support organs, the macrophages are part of the immune system so they function in getting rid of bacteria.
Location of this tissue is found throughout the body under the epithelial tissue, surrounds capillaries, and makes up the basement membrane which anchors the epithelial tissue above.
Loose Areolar Connective Tissue
