W1SAQ

The main functions of connective tissue are to provide structural and metabolic support to other tissues, protection, transport, repair, and storage.

The two main components of connective tissue are cells and extracellular matrix (ECM).

The two types of connective tissue cells are resident (fixed) cells and wandering (transient) cells.

The function of dense irregular connective tissue is to provide strength and resistance to stretch and tearing in multiple directions.

Elastic connective tissue is found in the lungs, elastic arteries, and some ligaments.

The main components of loose areolar tissue are all three types of fibers (collagen, elastic, and reticular), abundant ground substance, and several different cells.

The functions of white adipose tissue are fat storage, energy and insulation, and synthesis of hormones and growth factors.

Mast cells are responsible for inflammatory and allergic responses. They contain granules that release histamine and heparin, and they also have the ability to kill bacteria.

Collagen fibers provide mechanical and structural support for tissues. They have high tensile strength and make up the majority of the extracellular matrix.

Reticular fibers provide a supporting framework for the cellular constituents of various tissues and organs. They are associated with high levels of glycoproteins and are found in reticular tissue.

Elastic fibers are located in the skin, lung, and bladder. Their main function is to allow tissues to respond to stretch and distension.

The function of the cytoskeleton is to maintain the structural integrity of cells, facilitate movement of cell organelles, cell locomotion, and muscle fiber contraction.

The function of the rough endoplasmic reticulum (rER) is to synthesize proteins and transport them in vesicles.

The Golgi apparatus completes post-translational modifications, sorts and packages the products synthesized by the cell, and is involved in cellular secretion through exocytosis.

The function of mitochondria is to generate energy in the form of ATP through cellular respiration.

The function of keratinized epithelium is protection and prevention of water loss. It is located in the epidermis.

The function of nonkeratinized epithelium is protection and secretion. It is located in the mouth, esophagus, larynx, vagina, and anal canal.

Transitional epithelium is characterized by cells that change form according to the degree of distension. They are flat (squamous) when stretched and cuboidal when relaxed. The function of transitional epithelium is protection and distensibility. It is located in the lining of the urinary bladder, ureters, and renal calyces.

The main function of fibroblasts in connective tissue is synthesis and secretion of ground substance and connective tissue fibers, including collagen and elastic or reticular fibers, in the extracellular matrix (ECM).

The two types of adipocytes are white adipocytes and brown adipocytes. White adipocytes are specialized for fat storage, energy and insulation, and are involved in the synthesis of hormones and growth factors. Brown adipocytes are rich in mitochondria and are involved in heat generation and non-shivering thermogenesis.

Macrophages develop from monocytes and have an irregular shape with short branched projections. Their main function is to destroy bacteria and cellular debris through phagocytosis.

Undifferentiated mesenchymal cells are primitive stem cells found in connective tissue. They can transform into active fibroblasts by developing organelles essential for collagen synthesis and secretion. This transformation occurs during early development and during wound healing.

The main function of epithelial tissue is covering, lining, and protecting surfaces, as well as secretion, absorption, sensation, and contractility.

Epithelial tissue consists of an uninterrupted layer of tightly packed cells with one or several layers, including apical (free) and basal layers. It is polarized, with a free surface (apical surface) exposed to the outside and a basal surface attached to the underlying connective tissue. The basement membrane, formed by secretion of both epithelial cells and cells in connective tissue, functions as a selectively permeable filter between the epithelium and connective tissue.

The specializations of the cell surface in epithelial tissue include microvilli, which are folds of the plasma membrane that increase surface area and absorption, and cilia, which are projections of the plasma membrane involved in locomotion.

The different types of epithelia include simple squamous epithelium, simple cuboidal epithelium, simple columnar epithelium, pseudostratified epithelium, and stratified squamous epithelium.