স্পেশাল বিসিএস (স্বাস্থ্য) - লং কোর্স

Smooth muscle fibers are individual small, fusiform (tapering) cells, linked by numerous gap junctions.Thin and thick filaments in smooth muscle fibers do not form sarcomeres, and no striations are present. Branching is absent.

Osteocytes (Gr. osteon, bone + kytos, cell), which are found in cavities (lacunae) between bone matrix layers (lamellae), with cytoplasmic processes in small canaliculi (L. canalis, canal) that extend into the matrix

Intramembranous ossification, by which most flat bones begin to form, takes place within condensed sheets (“membranes”) of embryonic mesenchymal tissue. Most bones of the skull and jaws, as well as the scapula and clavicle, are formed embryonically by intramembranous ossification.

Periosteum is a layer of dense connective tissue on the outer surface of bone, bound to bone matrix by bundles of type I collagen called perforating (or Sharpey) fibers.

Fibroblasts are the most common cells in connective tissue proper, produce and maintain most of the tissue’s extracellular components. Fibroblasts synthesize and secrete collagen (the most abundant protein of the body) and elastin, which both form large fibers, as well as the GAGs, proteoglycans, and multiadhesive glycoproteins that comprise the ground substance.

Most tissues undergo cell turnover with slow cell division and cell death. Nerve tissue and cardiac muscle are exceptions because their differentiated cells cannot undergo mitosis.

Uniaxial- elbow
Biaxial- wrist
Multiaxial- shoulder/hip

Osteoclast helps in bone remodelling by bone resorption activity.

Unique transitional epithelium or urothelium lines much of the urinary tract, extending from the kidneys to the proximal part of the urethra, and is characterized by a superficial layer of large, dome-like cells sometimes called umbrella cells.

Adherent or anchoring junctions, formed by interacting proteins of the cadherin family, are points of strong attachment holding together cells of the epithelium.

Stereocillia are long microvilli with specialized mechanosensory function in cells of the inner ear and for absorption in tissues of the male reproductive tract.