Why are adipose tissue, blood, and bone all considered to be connective tissues? Why are adipose tissue, blood, and bone all considered to be connective tissues? They have a common origin: the embryonic tissue mesenchyme. They have the same types of cells. They connect to each other. They all have collagen and elastic fibers in their extracellular matrix.

"They all have collagen and elastic fibers in their extracellular matrix".

Explanation:

The connective tissue, also known as support tissue, supports and connects all the other tissues and organs in the body. Every substance exchange between epitheliums, muscles, nerves and the vascular system must be done with the connective tissue as an intermediate.

According to its specialization, there are different kinds of connective tissue, such as cartilage, blood, bony tissue, or lymphatic tissue, among others. Each type of connective tissue has its own cell type according to its functions. Cellular types, fibers, and aqueous medium appear in different amounts in different parts of the organism.

The connective tissue is composed of cells that are very separated from each other because of the abundant extracellular matrix, which is produced by fibroblasts, a predominant cell population. The extracellular matrix has fibrillar proteins of different nature such as collagen, fibrillin, and elastin that determine tension properties. There are also adessive proteins such as fibronectin and laminin. All of these proteins are included in a medium that contains water, salts, GAGs, proteoglycans, glycoproteins and other macromolecules that confer turgidity and facilitate diffusion. The properties of this matrix in different connective tissues mark the difference between each other.

The connective tissue originates in the mesoderm, which in the early stages of development, differentiates in an embryonary connective tissue called mesenchyme.