11th Objective Biology - Tissues

A brush border (striated border or brush border membrane) is the microvilli-covered surface of simple cuboidal epithelium and simple columnar epithelium cells found in certain locations of the body. It increases absorption.

Hemidesmosomes are asymmetrical and are found in epithelial cells connecting the basal face of the cell to basal lamina.

Tonofibrils, discovered by Rudolf Heidenhain and first described in detail by Louis-Antoine Ranvier are cytoplasmic protein structures in epithelial tissues that converge at desmosomes and hemidesmosomes.

The terminal bronchioles initially have a ciliated columnar epithelium that soon transits to a low cuboidal epithelium.

The basal lamina is a layer of extracellular matrix secreted by the epithelial cells, on which the epithelium sits. It is the thinnest layer.

A pseudostratified epithelium is a type of epithelium that, although comprising only a single layer of cells, has its cell nuclei positioned in a manner suggestive of stratified epithelia.

Reticular and fibrous lamina are visible under electron microscope.

Endothelium of blood vessels and mesothelial lining of coelomic cavities can be classified under squamous epithelium.

Tight junction is a specialized connection of two adjacent animal cell membranes, such that the space usually lying between them, is absent.

The 'Brush Border' of intestines is an example of simple epithelium.

The term given to the single layered epithelia is simple epithelium.

The basement membrane is a thin, fibrous, extracellular matrix of tissue that separates the epithelium (skin, respiratory tract, gastrointestinal tract, etc.), mesothelium (pleural cavity, peritoneal cavity, pericardial cavity, etc.) and endothelium (blood vessels, lymph vessels, etc.) from underlying connective tissue. It is bi-layered.

Simple squamous epithelium is found in lining areas where passive diffusion of gases occur. For example, skin, walls of capillaries, linings of the pericardial, pleural and peritoneal cavities, as well as the linings of the alveoli of the lungs.

Cells of simple squamous epithelium are flat with flattened/rounded nucleus. It is also called pavement epithelium due to its tile-like appearance.

Epithelial tissues are derived from all of the embryological germ layers from ectoderm (e.g., the epidermis); from endoderm (e.g., the lining of the gastrointestinal tract); from mesoderm (e.g., the inner linings of body cavities).

Epithelium of the gut originates from the endoderm.

The basement membrane is a thin, fibrous, extracellular matrix of tissue that separates the epithelium (skin, respiratory tract, gastrointestinal tract, etc.), mesothelium (pleural cavity, peritoneal cavity, pericardial cavity, etc.) and endothelium (blood vessels, lymph vessels, etc.) from underlying connective tissue . It is bi- layered.

Ciliated columnar epithelium moves mucus and other substances via cilia and is found in the upper respiratory tract and the fallopian tubes.

Cell multiplication and differentiation are the essential criteria for tissue formation. It also involves changes in the activation of certain genes for morphogenetic development.

Marcello Malpighi was an Italian biologist and physician, who is referred to as the "Father of microscopical anatomy, histology, physiology and embryology."

Specialized cells in a tissue are independent of other cell types in the tissue.

The branch involved in the study of animal tissues is called histology.

Epithelial tissues are avascular.

In biology, tissue is a cellular organizational level intermediate between cells and a complete organ. A tissue is an ensemble of similar cells from the same origin that together carry out a specific function.

The term 'tissue' was coined by Bichat.

The hardest tissue in the human body is tooth enamel. Tooth enamel is the thin, hard and white covering that protects the dentin of the teeth.

Glycoproteins are proteins that contain oligosaccharide chains (glycans) covalently attached to polypeptide side-chains. The intercellular substance in epithelial tissues is mainly composed of glycoproteins.

The free surface of epithelial cells faces outside environment.

The epithelia of body cavities that are connected to the external environment protect themselves by secreting large amount of mucus by numerous mucus-secreting cells.

An epithelial membrane consists of a continuous sheet of cells, one or more layers thick, which is attached to the underlying connective tissue by a basement membrane. The cells are joined together at specialized regions called cell junctions.