TISSUES

• What is the definition of tissues in anatomy and physiology?

  A group of cells with similar structure and function
• What is histology?

  The study of tissues
• What are the four main types of tissues?

  Epithelial, connective, muscle, and nervous tissues
• What is the primary function of epithelial tissues?

  To cover or line surfaces of the body
• What are examples of epithelial tissues?

  Skin, hair, and nails
• What are exocrine and endocrine glands?

  Glands that secrete substances such as hormones
• What characterizes connective tissues?

  They are diverse and make up part of every organ in the body
• What is a key feature of muscle tissues?

  A tissue that contracts or shortens
• What is the role of nervous tissues?

  To coordinate and control many body activities
• What are the characteristics of epithelial tissues?

  Mostly composed of cells, covers body surfaces, distinct cell surfaces, avascular, and capable of regeneration
• What are the distinct cell surfaces of epithelial tissues?

  Free (apical), lateral, and basal surfaces
• What is the function of the basement membrane in epithelial tissues?

  It attaches epithelial cells to underlying tissues and supports cell migration during repair
• Why are cell and matrix connections important in epithelial tissues?

  They support the cells
• What does it mean for epithelial tissues to be avascular?


  There is no presence of blood vessels
• What are the functions of epithelial cells?

  Protect underlying structures, act as a barrier, permit passage of substances, secrete substances, and absorb substances
• How can epithelial tissues be classified?

  By cell layers (simple, stratified, pseudostratified) and cell shapes (squamous, cuboidal, columnar, transitional)
• What is simple epithelial tissue?


  A single layer of cells
• What is stratified epithelial tissue?

  More than one layer of cells
• What is pseudostratified epithelial tissue?

  Consists of one layer of cells that appears falsely stratified
• What are the shapes of epithelial tissues?

  Squamous, cuboidal, columnar, and transitional
• What is simple squamous epithelium?


  A single layer of thin, flat cells
• What is simple cuboidal epithelium?


  A single layer of cube-like cells that carry out active transport, facilitated diffusion, or secretion
• What is the function of cilia in simple cuboidal epithelium?

  Used for moving substances or particles that should not be present in our bodies
• What is transitional epithelium?

  A special type of stratified epithelium that can be greatly stretched
• What is the role of free cell surfaces in epithelial tissues?

  They face away from underlying tissues and can be smooth or lined with microvilli and cilia
• What are microvilli?

  Structures that increase surface area
• What are cell connections in epithelial tissues?

  Structures that hold one cell to another or to the basement membrane
• What are desmosomes?

  Mechanical links that bind cells together
• What are tight junctions?

  Structures that prevent the passage of materials between epithelial cells
• What are gap junctions?


  Small channels that allow molecules and ions to pass from one epithelial cell to an adjacent one
• What is the function of glands in epithelial tissue?

  They secrete substances such as hormones
• What is simple columnar epithelium?


  A single layer of tall, thin cells that perform complex functions
• What are goblet cells?

  Cells that contain mucus and secrete it to the free surface
• What is pseudostratified columnar epithelium?

  Epithelium that secretes mucus which covers its free surface
• What is stratified squamous epithelium?


  Epithelium that forms a thick layer consisting of several layers of cells
• What are the two types of stratified squamous epithelium?

  Keratinized and nonkeratinized
• What is keratinized stratified squamous epithelium?

  The outer layer of the skin composed of keratinized cells
• What is nonkeratinized stratified squamous epithelium?

  Epithelium present in the mouth that provides protection against abrasion
• What is stratified cuboidal epithelium?

  Epithelium consisting of more than one layer of cuboidal cells
• Where is stratified cuboidal epithelium found?

  In sweat gland ducts, ovarian follicular cells, and salivary glands