Atlas of plant and animal histology

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Virtual microscopy


Image : joint of a rat, with associated structures. Stained with hematoxylin and eosin, and Alcian blue.

Epidermis: epithelial layer of the skin. A thin skin is shown in this image. The epidermis is made up of a few keratinocyte layers, and the stratum corneum is not much developed.

Dermis: layer of the skin consisting of irregular dense connective tissue, which is found immediately below of the epidermis.

Hair follicles: they are skin specializations that produce the hair of mammals. They also release fatty substances to the skin surfaces. In this image, the hair follicles are cut transversely at the level of the sebaceous glands. That is why sebaceous gland cells appear around the hair follicle canal. The hair is missing.

Compact bone: it is a type of bone that usually forms the outer region of the bone. Compact bone shows osteocytes and a very dense extracellular matrix, both arranged in tightly packaged layers.

Trabecular bone: or spongy bone. Trabecular bone is organized in plates and trabeculae, with osteocytes and extracellular matrix organized in a more irregular way than the compact bone. The bone marrow is found in cavities of the trabecular bone.

Bone marrow: it is the tissue found in the cavities of the trabecular bone. The bone marrow consists of hematopoietic cells and cells of the immune system. In this image, many adipocytes can be also observed (rounded clear structures).

Periostium: it is the layer of connective tissue that covers the outer surface of the bone. la capa de tejido conectivo que recubre la superficie externa del hueso.

Endostium: it is the layer of connective tissue that lines the inner surface of trabecular bone cavities, and it surrounds the bone marrow.

Articular cartilage: it is a type of hyaline cartilage found in the joints, at the region of the bones under more mechanical friction. The function of the articular cartilage is withstanding this mechanical friction at the joints and protect the bones.

Articular capsule: it is a thin layer of connective tissue that encloses the joint and keeps the synovial fluid confined.

Fibrous cartilage: it is a type of cartilage with mixed features between the hyaline cartilage and the dense regular connective tissue. The fibrous cartilage cells are irregularly scattered, but they can be also organized in rows. Chondrocytes of fibrous cartilage and fibroblasts are sometimes difficult to distinguish from each other.

Tendon: it is dense regular connective tissue that connects the skeletal muscle with the bone. Fibrocartilage may be found between the tendon and the bone.