Search results
Results From The WOW.Com Content Network
The periosteum is a membrane that covers the outer surface of all bones, [1] except at the articular surfaces (i.e. the parts within a joint space) of long bones. (At the joints of long bones the bone's outer surface is lined with "articular cartilage", a type of hyaline cartilage.)
Each osteon consists of concentric layers, or lamellae, of compact bone tissue that surround a central canal, the Haversian canal. The Haversian canal contains the bone's blood supplies. The boundary of an osteon is the cement line. Each Haversian canal is surrounded by varying number (5-20) of concentrically arranged lamellae of bone matrix.
Lamella, in cell biology, is also used to describe the leading edge of a motile cell, of which the lamellipodia is the most forward portion. [5] The lipid bilayer core of biological membranes is also called lamellar phase. [6] Thus, each bilayer of multilamellar liposomes and wall of a unilamellar liposome is also referred to as a lamella.
The cell also exhibits a reduced size endoplasmic reticulum, Golgi apparatus and mitochondria, and cell processes that radiate largely towards the bone surfaces in circumferential lamellae, or towards a haversian canal and outer cement line typical of osteons in concentric lamellar bone. [5]
They are part of the outer fibrous layer of periosteum, entering into the outer circumferential and interstitial lamellae of bone tissue. Sharpey's fibres also attach muscle to the periosteum of bone by merging with the fibrous periosteum and underlying bone as well.
In fish, gill lamellae are used to increase the surface area in contact with the environment to maximize gas exchange (both to attain oxygen and to expel carbon dioxide) between the water and the blood. [3] In fish gills, there are two types of lamellae, primary and secondary. The primary gill lamellae (also called gill filament) extends from ...
5. Vas spirale. 6. Zona arcuata, and 6’, zona pectinata of the basilar membrane, with a, its hyaline layer, B, its connective-tissue layer. 7. Arch of spiral organ, with 7’, its inner rod, and 7”, its outer rod. 8 feet (2.4 m) of the internal rods, from which the cells are removed. 9 feet (2.7 m) of the external rods. 10.
The middle lamella is a layer that cements together the primary cell walls of two adjoining plant cells. It is the first formed layer to be deposited at the time of cytokinesis. [1] The cell plate that is formed during cell division itself develops into middle lamella or lamellum. The middle lamella is made up of calcium and magnesium pectates. [2]