Anatomy & Physiology I and II

Anatomy & Physiology Study Guide

©2018 Achieve Test Prep Page 39 of 367 Defending the body from invading microbes. Connective tissue is rich in blood supply and consists of cells scattered throughout an intercellular matrix of protein fibers. It also consists of a ground substance, which is what binds the cells together. Connective tissue is derived from two types of cells: those whose names end in -blasts (which have a high capacity for cell division and are responsible for making the matrix) and those whose names end in -cyte (matured blasts that keep the matrix together). All connective tissues have mesenchyme as their common tissue of origin and have varying degrees of vascularity. Classification of Connective Tissue Connective Tissue Proper Connective tissue proper contains extracellular fibers, a viscous (syrupy) ground substance, and a diverse cell population. Some of the cells (including fibroblasts, fibrocytes, adipocytes, and mesenchymal cells) function in local maintenance, repair, and energy storage. These cells are permanent residents of the connective tissue. Other cells defend and repair damaged tissue, as seen with macrophages, mast cells, lymphocytes, plasma cells, and microphages. A network of connective tissue proper connects internal organs and systems together. This network consists of the superficial fascia (the subcutaneous layer separating the skin from underlying tissues and organs), the deep fascia (dense connective tissue), and the subserous fascia (the layer between the deep fascia and the serous membranes that line body cavities). Connective Tissue Proper: Loose Loose connective tissues are the “packing materials” of the body. They fill the spaces between organs, cushion and stabilize specialized cells in many organs, and support epithelia. These tissues surround Types of Secretions Exocrine glands are further distinguished by the type of secretion produced. Serous glands secrete a watery solution that contains enzymes. Mucous glands secrete mucins that hydrate to form mucus. Mixed exocrine glands contain more than one type of gland cell and may produce two different exocrine secretions, one serous and the other mucous. 4.2 Connective Tissue Connective tissue provides a protective structural framework for other tissue types. Connective tissues include bone, cartilage, and blood. These tissues provide structure, store energy reserves, and transport materials throughout the body. Among the specific functions of connective tissues are the following: • Establishing a structural framework for the body. • Transporting fluids and dissolved materials. • Protecting delicate organs. • Supporting, surrounding, and interconnecting various types of tissue. • Storing energy reserves. •