Question

Endosteum is composed of
A. White fibrous connective tissue
B. Reticular connective tissue
C. Yellow fibrous connective tissue
D. Areolar connective tissue

Answer 1

Endosteum is a thin choroid, consisting of connective tissue, which covers the inner surface of the bone tissue and forms the long bones medullary cavity. The endosteum is composed of tissue which is located in the liver, spleen, lymph nodes, thymus, tonsils, bone marrow and inner layers of the intestinal wall. Since connective tissue forms the supporting frame (stroma) of many organs, it is specially tuned to provide strength and support.

Complete answer:
Anatomically, the endosteum is a thin layer of connective tissue that covers the surface of the bone tissue that makes up the medullary cavity of the long bone.

Reticular connective tissue: This tissue is made up of stellate reticulocytes in which protoplasmic processes combine to form cellular tissue. Reticular fibres are present in reticular cells. They are composed of the protein reticulin. Some other cells are also present, such as matrix and macrophages, lymphocytes and fat cells. The reticular connective tissue is located in the liver, spleen, lymph nodes, thymus, tonsils, bone marrow and inner layers of the intestinal wall. Since connective tissue forms the supporting frame (stroma) of many organs, it is specially tuned to provide strength and support. It also helps smooth muscle cells connect. Reticular cells are phagocytes and form defense mechanisms in the body.
Reticular connective tissue is a type of connective tissue. It has a network of reticular fibres composed of type III collagen. Reticular fibres are found only in these types (Endosteum), as well as in the reticular connective tissue.

Hence, the correct answer is option (B).

Additional information:
White fibrous connective tissue: It is composed of shiny white fibres. They are thin, without branches. The fibres do not move singly but in bundles. Tufts of white fibres are wavy (irregular) and move in different directions. Individual fibres do not branch, but the bundles branch freely, and the branches communicate with each other. Space thus formed is occupied by the areolar tissue. These cells are compressed by adjacent bundles of white filaments, and they are angular star-shaped in cross-section. These stellate cells are usually located in the cross-section of the tendon.

Yellow elastic connective tissue: This tissue is mainly composed of a thicker, branched network of yellow fibres. There are also white fibres, but they are very thin. Fibroblasts are poorly distributed. It also contains mast cells, macrophages, and often some fat cells. (I) Yellow fibrous ligament (ligament): The yellow elastic connective tissue forms ligaments called ligaments that connect bones to bones. Yellow fibrous Sheets: The Sheets formed by this tissue look like blood vessels, lungs, bronchioles, vocal cords, laryngeal cartilage, organs, spleen capsules and ligamentous plates that connect adjacent vertebrae. Considerable strength and excellent elasticity. This allows the various organs to be stretched. In the immortal "mother", the arteries are intact due to well-preserved elastic fibres. Sprains are caused by overstretching (stretching) the ligaments.

Areolar tissue (loose connective tissue): This tissue is the most abundant connective tissue in the animal's body. A thin thread that crosses in all directions is so named because it leaves a small space called the areola. Substance, matrix, white, yellow and reticular fibres and cells, fibroblasts, mast cells, macrophages (= tissue cells or plasma cells), lymphocytes, plasma cells, mesenchymal cells. Fat cells can be viewed in small groups. Descriptions of matrix, fibres and cells are already contained in the general structure of connective tissue. As mentioned earlier, areola tissue is the most abundant connective tissue in the body. It is found under the skin as the lining of the digestive tract and airways, between the lobes and lobules of the bone marrow, glandular components, and between the muscles, nerves and blood vessels in the mesentery and surrounding subcutaneous tissue.

Note: The outer surface of the bone is lined with a thin layer of connective tissue, which in shape and function is very similar to the endosteum and known as periosteum.
The reticular fibres are like white fibrous tissue with the following difference:
• They are thinner, loosely branched and resist digestion of proteins
• They are selectively stained with solutions of silver oxide or carbonate. Therefore, it is called argyrophil fibre. The gap is very small and is mainly occupied by lymphatic and tissue fluid. These tissue cells belong to the so-called reticuloendothelial system. Reticular tissue is common. It forms the basement membrane of many epithelia, the skeleton of many organs that support the basic cellular elements