Level of Organisation

• Tissues in the human body


  • Muscle tissue
  • Epithelial tissue
• Leaf function

  1. Mesophyll tissue carries out photosynthesis

  2. Xylem tissue transports water and mineral ions to enable photosynthesis

  3. Phloem tissue transports food substances made in the leaf to other parts of the plant
• Organ


  Consists of more than one kind of tissue, all working together to perform a specific function
• Tissues in plants

  • Epidermis (covers the surface of leaves, stems, and roots)
  • Mesophyll tissue in leaves (carries out photosynthesis)
• Organ system


  Consists of several organs working together for a common purpose
• An organism is made up of various organ systems working together
• Tissue

  A group of cells with similar structures that work together to perform a specific function
• Stomach function

  1. Gland tissue secretes enzymes to digest food

  2. Muscle tissue contracts to churn food and mix it with digestive enzymes

  3. Nerve tissue detects the presence of food in the stomach and causes gland tissue to secrete digestive enzymes
• An organ system is made up of several organs working together
• Organ systems in the human body

  • Digestive system
  • Circulatory system
  • Respiratory system
• The phloem tissue transports the food substances made in the leaf to other parts of the plant
• Red blood cell carries oxygen around the body, has a biconcave shape for efficient oxygen transport, and contains haemoglobin
• Root hair cell's job is to absorb water and minerals efficiently due to its long and narrow structure
• Organ system consists of various organ systems such as the respiratory system and shoot system
• Palisade cell found on the surface of leaves performs photosynthesis with numerous chloroplasts for maximum sunlight absorption
• Nerve cell carries electrical signals called impulses
• Ciliated cell found in the throat/airways sweeps mucus & dirt back up the throat to prevent them from entering the lungs
• Specialized cells include sperm cell, egg cell, root hair cell, ciliated epithelium, palisade cell, red blood cell, and nerve cell