Lesson 4 Histology: Tissues and Membranes Flashcards
the branch of biology that deals with the microscopic examination of structure, organization and functions of tissues
Histology
a group of cells having similar structure, and performs specific function.
tissue
makes up the covering of exterior surfaces of the body, internal lining of cavities and passageways, and form certain glands.
Epithelial tissue
binds the cells and organs of the body together.
Connective tissue
provides movement by contracting forcefully
Muscle tissue
excitable and capable of sending electrochemical signals in the form of nerve impulses communicate between different regions and organs of the body
Nervous tissue
controls the transfer of materials across that allows selective transport of molecules and ions.
epithelial cells
are most concerned with absorption, secretion and filtration. Because they are very thin, protection is not one of their specialty
Simple epithelial Cells
single layer of thin squamous cells fit closely together like floor tiles.
Simple Squamous Epithelium
one layer of cuboidal cells resting on basement membrane, is common in glands and their ducts like in salivary gland and pancreas
Simple Cuboidal Epithelium
made up of single layer of tall cells that fit closely together.
Simple Columnar Epithelium
which produce a lubricating mucus, are often seen in this type of epithelium
Goblet cells
Epithelial membranes that line the body cavities, open to the body exterior
mucus membranes or mucosae
all of the cells of pseudostratified columnar epithelium rests on the basement membrane; some cells are shorter that others, and their nuclei appear at different heights above the basement membrane thus
Pseudostratified Columnar Epithelium
The most common stratified epithelium in the body. Consists of several layers of cells, found in sites that receive a good deal of abuse or friction, such as the esophagus, the mouth and outer portion of the skin.
Stratified Squamous Epithelium
usually just two layers of cells with the surface cells being cuboidal in shape, specialized in selective absorption and secretion by the glands into the blood or lymph vessels.
Stratified Cuboidal Epithelium
are columnar cells but its basal cells vary in size and shape. They are fairly rare in the body, being found mainly in the ducts of large organs.
Stratified Columnar Epithelium
is a highly modified squamous epithelium that forms the lining of only a few organs – the urinary bladder, the ureters and the part of the urethra, which are subject to considerable stretching.
Transitional Epithelium
consists of one or more cells that make and secrete a particular product
Gland
typically contain protein molecules in a watery fluid
secretion
are known as ductless glands. Their secretions (all hormones) diffuse directly into the blood vessels. Examples are thyroid gland, adrenal glands, and pituitary gland
Endocrine glands
have ducts, and their secretions empty through the ducts to the epithelial surface. It includes sweat glands, oil glands and salivary glands
Exocrine gland
Connective tissues are made up of many different types of cells plus varying amounts of a non-living substance found outside the cells
extracellular matrix
composed of bone cells sitting in cavities called lacunae and surrounded by layers of a very hard matrix that contains calcium salts in addition to large numbers of collagen fibers.
Bone or Osseous tissue
less hard and more flexible than the bone. It is only in few places in the body
Cartilage
which has abundant collagen fibers hidden by a rubbery matrix with a glassy (hyaline = glass), blue-white appearance
hyaline cartilage
forms the cushion-like disks between the vertebrae of the spinal column
Fibrocartilage
found where a structure with elasticity is desired. For example, it supports the external ear
Elastic cartilage
It is also called dense fibrous tissue, its main matrix element is the collagen crowded with rows of fibroblasts (fiber-forming cells) that manufacture the fibers
DENSE CONNECTIVE TISSUE
are softer, have more cells and fewer fibers than any connective tissue type except blood.
Loose connective tissue
