Histology: Connective Tissues Multiple Choice Quiz

Connective Tissues

• Connective tissues make up a large part of the body and provide support, structure, and function to organs and tissues.
• Connective tissues fill the spaces between other tissues and form organs.

Characteristics of Connective Tissues

• Connective tissues have relatively few cells that are not necessarily connected.
• Connective tissues are immersed in a considerable quantity of extracellular matrix.
• Extracellular matrix is a composite of "filler material" (ground substance) and varying quantities of fibers.

Functions of Connective Tissues

• Form the bulk of organs.
• Fill the spaces between other tissues and bind organs together.
• Support organs by forming fascia and sheaths, ligaments, and tendons.
• Form support structures in the joints, such as joint capsules, synovial membranes, and tendon sheaths.
• Store calcium, fat, immune cells, water, and many bodily chemicals, such as growth factors and hormones.
• Insulate (mostly due to stored fat, but also by forming the dermis of the skin).
• Transport substances through the body via blood.

Types of Connective Tissues

• Ordinary connective tissues:
  • Loose connective tissue (areolar, reticular, adipose)
  • Dense connective tissue (regular)
• Specialized connective tissues:
  • Cartilage (hyaline, fibrocartilage, elastic)
  • Bone (compact, irregular, spongy)
  • Blood and blood-forming tissues

Ground Substance

• A gel-like material that fills the spaces between connective tissue cells.
• A mixture of glycoproteins, glycoaminoglycans (such as hyaluronic acid), and proteoglycans.
• Can be very fluid (e.g., vitreous humor in the posterior cavity of the eye) or calcified (e.g., bone).
• Determines the permeability of a connective tissue and its ability to store water.

Fibers in Connective Tissues

• Three types of fibers:
  • Collagen fibers (found in tendons, provide tensile strength and resistance to longitudinal stretching)
  • Elastic fibers (stretchy in all directions, help tissues return to their previous shapes after extension)
  • Reticular fibers (very fine collagen fibers, form a net-like structure, wrap around organs and protect their integrity)

Production and Maintenance of Connective Tissues

• Formed by undifferentiated cells (whose names end in "-blast") that create new ground substance and connective tissue fibers.
• When these "-blast" cells become surrounded by the ground substance they are producing, they are considered mature and are referred to by names that end in "-cyte".