Skip to main content
Back

Anatomy & Physiology: Histology and Tissue Types

Control buttons has been changed to "navigation" mode.
1/21
  • What is histology?

    Histology is the study of the normal structures of tissues, which are groups of structurally and functionally related cells and their extracellular matrix performing common functions.

  • What are the four primary tissue types?

    1. Epithelial tissues: tightly packed sheets covering body surfaces.
    2. Connective tissues: connect and support other tissues.
    3. Muscle tissues: generate force by contracting.
    4. Nervous tissues: generate and transmit messages.

  • What are the two main components of the extracellular matrix (ECM)?

    The ECM consists of ground substance (fluid, nutrients, ions) and protein fibers (collagen, elastic, reticular fibers).

  • What is the function of collagen fibers in the ECM?

    Collagen fibers provide tensile strength, resisting pulling and stretching forces.

  • Describe the function of elastic fibers in connective tissue.

    Elastic fibers allow tissues to stretch up to 1.5 times their length and return to resting length, providing elasticity.

  • What are tight junctions and their function?

    Tight junctions hold cells closely together, making the space between impermeable to macromolecules.

  • How are epithelial tissues classified?

    By number of cell layers (simple or stratified) and cell shape (squamous, cuboidal, columnar).

  • What is the function of simple squamous epithelium and where is it found?

    Adapted for rapid diffusion; found in lung air sacs, kidney tubules, and lining blood vessels.

  • What distinguishes keratinized stratified squamous epithelium?

    Apical layers are dead, filled with keratin, making it tough and resistant to friction; found in outer skin layers.

  • What is the difference between endocrine and exocrine glands?

    Endocrine glands secrete hormones into the bloodstream; exocrine glands release products onto body surfaces or into ducts.

  • Describe merocrine secretion.

    Secretory cells package products in vesicles and release them by exocytosis without cell damage.

  • What are fibroblasts and their role in connective tissue?

    Fibroblasts are resident cells that produce protein fibers and ground substance of the ECM, especially collagen.

  • Where is loose connective tissue found and what is its function?

    Found beneath epithelium and in membranes; supports blood vessels and houses immune cells.

  • What is the main characteristic of dense irregular connective tissue?

    Disorganized collagen bundles that resist tension in multiple directions; found in dermis and organ capsules.

  • What are the three types of cartilage and their key features?

    1. Hyaline: glossy, fine collagen; found on bone ends.
    2. Fibrocartilage: dense collagen bundles; found in joints.
    3. Elastic: elastic fibers; found in ear and larynx.

  • What are osteoblasts, osteocytes, and osteoclasts?

    Osteoblasts build bone ECM; osteocytes maintain bone; osteoclasts resorb bone by breaking down ECM.

  • What are the main functions of blood cells?

    Erythrocytes transport oxygen; leukocytes provide immunity; platelets aid in blood clotting.

  • What distinguishes skeletal muscle tissue?

    Voluntary, striated, multinucleated cells attached to skeleton for body movement.

  • What are intercalated discs in cardiac muscle?

    Specialized connections containing gap junctions and tight junctions that allow coordinated heart contractions.

  • What are the main components of a neuron?

    Cell body (soma), axon (transmits impulses), and dendrites (receive signals).

  • What is tissue repair and what are the two main processes?

    Tissue repair replaces damaged cells; involves regeneration (same cell type replacement) or fibrosis (scar tissue formation).