2.1.4 Specialised cells

• How are cells specialised?

  By having different organelles for functions
• What determines which genes are expressed in a cell?

  Genes that are turned on will be transcribed
• What is the function of epithelial cells of the small intestine?

  To absorb nutrients
• How do microvilli relate to the function of epithelial cells?

  They increase the surface area for absorption
• What is the role of mitochondria in epithelial cells of the small intestine?

  To produce ATP for active transport
• What is the primary function of red blood cells?

  To transport oxygen
• Why do red blood cells lack a nucleus?

  To increase space for hemoglobin
• How does the biconcave shape of red blood cells benefit their function?

  It increases the surface area for oxygen transport
• What is the function of sperm cells?

  To fertilize the ovum
• How does the flagellum contribute to the function of sperm cells?

  It propels the sperm towards the ovum
• What is the role of mitochondria in sperm cells?

  To produce ATP for flagellum movement
• What does the acrosome in sperm cells contain?

  Digestive enzymes to hydrolyze ovum cells
• What are the levels of organization in biological systems?

  • Cells: Basic unit of life
  • Tissues: Groups of similar cells
  • Organs: Groups of tissues
  • Organ systems: Groups of organs
• What is the definition of epithelial tissue?

  Lines surfaces of organs
• How are alveoli specialized for their function?

  They have thin, flat cells for diffusion
• What is the function of goblet cells in the trachea?

  To create mucus that traps particles
• How does ciliated epithelium function in the trachea?

  It moves mucus out of the lungs
• How is the stomach specialized for digestion?

  It contains various tissues for food processing
• What role does smooth muscle play in the stomach?

  It churns and mixes stomach contents
• What is the function of the palisade mesophyll in leaves?

  To perform photosynthesis using chloroplasts
• How does the spongy mesophyll contribute to leaf function?

  It allows for gas exchange through air spaces
• What is the role of the epidermis in leaves?

  To protect the leaf and allow gas exchange
• What is the function of phloem in leaves?

  To transport sugars away from the leaf
• What is the function of xylem in leaves?

  To transport water and ions to the leaf