connective tissue

Examples of connective tissue in the following topics:

• Characteristics of Connective Tissue

  • Connective tissue (CT) is a one of the four main classes of tissues.
  • This offers great diversity in the types of connective tissue.
  • Connective tissue fibers provide support.
  • Three types of fibers are found in connective tissue:
  • They help the connective tissue to stretch and recoil.

• Connective Tissues: Loose, Fibrous, and Cartilage

  • Connective tissue is found throughout the body, providing support and shock absorption for tissues and bones.
  • The principal cell of connective tissues is the fibroblast, an immature connective tissue cell that has not yet differentiated.
  • The matrix in connective tissues gives the tissue its density.
  • Loose connective tissue, also called areolar connective tissue, has a sampling of all of the components of a connective tissue.
  • Cartilage is a connective tissue.

• Types of Connective Tissue

  • Connective tissue proper has two subclasses: loose and dense.
  • The functions of areolar connective tissue include the support and binding of other tissues.
  • This is loose connective tissue composed of adipocytes.
  • This is considered a specialized form of connective tissue.
  • It is an atypical connective tissue since it does not bind, connect, or network with any body cells.

• Structural Elements of Connective Tissue

  • Collagen is a group of naturally-occurring proteins found in animals, especially in the flesh and connective tissues of mammals.
  • It is the main component of connective tissue, and is the most abundant protein in mammals, making up about 25% to 35% of the whole-body protein content.
  • Elastic tissue is classified as "connective tissue proper. " The elastic fiber is formed from the elastic microfibril and amorphous elastin.
  • Elastic fibers are found in the skin, lungs, arteries, veins, connective tissue proper, elastic cartilage, periodontal ligament, fetal tissue, and other structures.
  • Reticular fibers or reticulin is a histological term used to describe a type of fiber in connective tissue composed of type III collagen.

• Arrangement of Fascicles

  • Skeletal muscle tissue is composed of numerous muscle fibers which are separated from adjacent muscles and other tissues by a layer of dense, elastic connective tissue termed the fascia.
  • Beneath the fascia in skeletal muscle is another layer of connective tissue termed the epimysium which is closely associated with the fascia.
  • The organization of connective tissue throughout and around a muscle provides strength and flexibility while distributing the force evenly.
  • Skeletal muscle is surrounded by a thick outer layer of connective tissue termed the fascia.
  • Each fascicle is surrounded by another layer of connective tissue termed the endomysium.

• Complex Tissue Structure

  • Animals, besides Parazoa (sponges), are characterized by specialized tissues such as muscle, nerve, connective, and epithelial tissues.
  • As multicellular organisms, animals differ from plants and fungi because their cells don't have cell walls; their cells may be embedded in an extracellular matrix (such as bone, skin, or connective tissue); and their cells have unique structures for intercellular communication (such as gap junctions).
  • Animals are also characterized by specialized connective tissues that provide structural support for cells and organs.
  • This connective tissue constitutes the extracellular surroundings of cells and is made up of organic and inorganic materials.
  • In vertebrates, bone tissue is a type of connective tissue that supports the entire body structure.

• Connective Tissues: Bone, Adipose, and Blood

  • Bone, adipose (fat) tissue, and blood are different types of connective tissue that are composed of cells surrounded by a matrix.
  • Bone, or osseous tissue, is a connective tissue that has a large amount of two different types of matrix material.
  • Adipose tissue, or fat tissue, is considered a connective tissue even though it does not have fibroblasts or a real matrix, and has only a few fibers.
  • Blood is considered a connective tissue because it has a matrix.
  • Adipose (fat) is a connective tissue composed of cells called adipocytes.

• Bursae and Tendon Sheaths

  • Joints are cushioned by small fluid-filled sacs called bursae and stabilized by tough bands of fibrous connective tissue called tendons.
  • Synovial joints are made up of five classes of tissues: bone, cartilage, synovium, synovial fluid, and tensile tissues composed of tendons and ligaments.
  • A tendon or sinew is a tough band of fibrous connective tissue that usually connects muscle to bone and is capable of withstanding tension.
  • Tendons connect muscle to bone and move the bones or structures to which they are attached.
  • Bursae occur at sites of shearing in subcutaneous tissue or between deeper tissues such as muscle groups and fascia.

• Tissues in Levels of Organization

  • The four basic tissue types are epithelial, muscle, connective, and nervous tissue.
  • Each tissue type has a characteristic role in the body:
  • Most organs contain more than one tissue type.
  • For example, the stomach consists of smooth muscle tissue for churning movement while it is innervated, but it is also supplied by blood, which is a connective tissue.
  • Cells form tissues, and tissues form organs.

• Characteristics of Epithelial Tissue

  • The human body consists of four types of tissue: epithelial, connective, muscular, and nervous.
  • Epithelial tissue covers the body, lines all cavities, and composes the glands.
  • In its role as an interface tissue, epithelium accomplishes many functions, including:
  • These protein connections hold the cells together to form a tightly connected layer that is avascular but innervated in nature.
  • The epithelial cells are nourished by substances diffusing from blood vessels in the underlying connective tissue.