Four types of tissues found in animals
epithelial, connective, muscle, and nervous
Epithelial tissue classified as
simple or stratified
Simple Epithelial tissue
has only one layer of cells
Stratified Epithelial tissue
has several cells layers
Simple squamous epithelium
characterized by flattened, irregulary shaped cells that form a continuous sheet.
Simple cuboidal epithelium
characterized by cube-shaped cells with a nucleus that is usually round and centrally located.
Simple columnar epithelium
composed of cells that are taller than they are wide, and the nucleus is located towards the base of the cell.
characterized by a fluid, semisolid, or solid matrix in which cells and fibers are embedded; four general catergories.
Connective Tissue Proper, cartilage, bone, and blood
Four general categories of connective tissue
Connective tissue proper
loose connective tissue, dense regular connective tissue and adipose tissue comprise this.
Loose connective (areolar) tissue
characterized by fibers that are irregularly arranged in the matrix; two types of fibers are present: collagen and elastic.
appear as blue-black strands randomly arranged in the matrix.
Dense Regular connective tissue
contains collagen fibers that are arranged in parallel. Between fibers are flattened rodlike nuclei of fibroblasts.
contains ___cells that are closely packed; cells appear empty because fat was removed during tissue preparation. Cytoplasm and nucleus located at periphery of cell.
connective tissue with semisolid matrix; within matrix are fibers and chondrocytes.
cartilage cells located within round-ovoid spaces called lacunae.
composed of collagen and chondrocytes
contains collagen fibers, chondrocytes, and elastic fiber that are found between lacunae.
consists of a hard matrix of calcium salts; the calcium salt makes it hard.
characterized by central (Haversian) canal.
Lacunae, which hold the osteocyte (bone cells), are arranged in concentric rings around the central Haversian canal.
composed of a fluid matrix.
numerous erythrocytes and few leukocytes present in matrix; some platelets scattered around.
three types of this kind of tissue; composed of muscle fibers.
Skeletal muscle fibers
characterized by fibers that have light and dark striping or cross-striations. Each fiber is multinucleated; nuclei are located of priphery of each fiber.
Cardiac muscle fibers
have cross-striations and are branched; adjacent fibers are separated by dark-staining structures called intercalated disks; single nucleus in each cardiac muscle fiber.
Smooth muscle fibers
have no cross-striations; single elongated or ovoid nucleus is present in each fiber.
composed of neurons and neuroglia (neuroglial cells)
consist of a cell body, dendrites, and an axon. Several Cytoplasmic processes radiate from the cell body, which holds the nucleus.
cannot be distinguished because cytoplasm is unstained in tissue prep; however, nuclei are visible as dots.