Chapter 2: Tissues

• What are tissues in multicellular organisms?


  Groups of cells that are similar in structure and work together for a specific function
• Why are tissues organized in a specific way?

  To maximize efficiency in performing a particular function
• Give examples of tissues.

  Blood, phloem, and muscle
• What are the two main types of plant tissues?

  • Meristematic Tissue
  • Permanent Tissue
• What is meristematic tissue?

  Simple living tissues capable of division and forming new cells
• What are the main features of meristematic tissues?

  Thin primary cell wall, absence of intercellular spaces, and dense cytoplasm
• How do plant tissues differ from animal tissues?

  • Plant tissues have a cell wall; animal tissues do not.
  • Some plant tissues are dead; all animal tissues are living.
  • Plant tissues require less energy; animal tissues require more energy.
  • Plant growth is confined to tips; animal growth is uniform.
  • Plant tissue organization is simple; animal tissue organization is complex.
• What is primary meristem?

  Meristem derived directly from the embryo contributing to primary growth
• What is secondary meristem?

  Meristem derived from primary permanent tissue contributing to diameter growth
• Where is apical meristem located?

  At the growing tips of stems and roots

  
• What is the function of intercalary meristem?

  Aids in longitudinal growth behind the apex of the plant

  
• What does lateral meristem give rise to?

  Vascular tissues
• What are simple permanent tissues?

  Tissues consisting of only one type of cells
• What is parenchyma tissue?

  Relatively unspecialized living cells with thin walls found beneath the epidermis
• What is the function of collenchyma tissue?

  Provides flexibility in plants, preventing breakage
• What is sclerenchyma tissue?

  Dead cells that impart hardness and stiffness to plants
• What are the types of complex permanent tissues?

  • Xylem
  • Phloem
• What does xylem conduct?

  Water and minerals
• What is the direction of flow in xylem?

  Mostly unidirectional from roots to apical
• What is the cell vitality in xylem?

  Three of four elements are dead, only xylem parenchyma is living
• What is the additional function of xylem?

  Provides mechanical strength to the plant
• What does phloem conduct?

  Organic solutes or food materials
• What is the direction of flow in phloem?

  May be bidirectional
• What is the cell vitality in phloem?

  Three of four elements are living
• What is the additional function of phloem?

  Performs no mechanical function for the plant
• What are the protective tissues in plants?

  • Epidermis
  • Cork
• What is the function of the epidermis?

  Protects against bad weather and water loss
• What are the functions of the epidermis?

  Safeguards the plant, minimizes water loss, facilitates gas exchange
• What are cork cells?

  Lifeless cells found at the outer edges of roots and stems
• What is the primary role of cork in plants?

  Offers protection and prevents desiccation
• What are the four types of animal tissues?

  • Muscular tissue
  • Nervous tissue
  • Connective tissue
  • Epithelial tissue
• What are the three types of muscular tissue?

  Smooth, cardiac, and striated (skeletal)
• What is smooth muscle tissue?

  Muscle tissue shaped like spindles found in organs with automatic movement
• What is cardiac muscle tissue?

  Muscle tissue found in the heart with branches and many nuclei
• What is striated (skeletal) muscle tissue?

  Muscle tissue with long, unbranched fibers and stripes
• What is nervous tissue?

  Special cells called neurons that form the nervous system
• What are cartilage tissues?

  Soft tissues in the ear, nose, trachea, and joints
• What are tendons?

  Connectors linking bones to muscles
• What are connective tissues?

  Cells embedded in a matrix present in solid, liquid, or jelly-like form
• What are bones?

  Cells surrounded by a matrix made of calcium and phosphate