Cells to Systems

• Levels of Organisation


  • Cell
  • Tissue
  • Organ
  • System
  • Organism
• Organs


  Structures composed of various tissues (often all four) together achieve a common function
• Systems


  Arrangements of organs which work together to carry out a major purpose in the body
• Tissue Types


  • Muscle tissue
  • Nervous tissue
  • Epithelial tissue
  • Connective tissue
• Epithelial tissue


  Form the interface between your body and the external environment
• Connective tissue


  Contains cells that are separated by an extracellular matrix (substance not made of cells)
• Types of Muscle Tissue

  • Skeletal/striated Muscle Tissue
  • Cardiac Muscle Tissue
  • Smooth Muscle Tissue
• Skeletal/striated Muscle Tissue


  • Contracts voluntarily
  • Attached to the skeleton
• Cardiac Muscle Tissue


  • Contracts involuntarily
  • Found in the heart walls
• Smooth Muscle Tissue


  • Contracts involuntary
  • Surrounds organs
• Nerve Cells


  • Sensory Neurons
  • Inter Neurons
  • Motor Neurons
• Sensory Neurons


  Carries information to the central nervous system
• Inter Neurons


  They pass the information passed from the sensory neurons up to the brain as well as to the motor neurons. They are in the CNS
• Motor Neurons


  Carries information from the CNS to the moving body parts