Cells

• What is a cell

  They are the basic unit of all forms of life. Different cells have different functions
• Name the 5 parts of a animal cell? Nucleus, cytoplasm, cell membrane, mitochondria and ribosomes.
• What does semi-permeable mean


  only some substances can pass through
• What is the function of the nucleus in a cell?


  Contains DNA and controls the cell's activities
• What is the function of the cytoplasm?


  Where most chemical reactions take place; it is a liquid gel with organelles suspended within it
• Where does aerobic respiration take place in a cell?


  In the mitochondria
• What is the role of the cell membrane?


  Controls the movement of substances into and out of the cell and is semi-permeable
• What is the function of ribosomes?


  A tiny organelle where protein synthesis takes place
• What is the function of chloroplasts in plant cells?


  Contain chlorophyll which absorbs light energy for photosynthesis and also contains enzymes needed for photosynthesis
• What is the function of the permanent vacuole in plant cells?


  Filled with cell sap to keep the cell turgid
• What is the composition of the cell wall in plant cells?


  Made from cellulose fibers, which strengthens the cell and gives support to the plant
• What are the main organelles in a plant cell and their functions?

  • Nucleus: Contains DNA and controls cell activities
  • Cytoplasm: Where most chemical reactions take place
  • Mitochondria: Where aerobic respiration occurs
  • Cell membrane: Controls movement of substances, semi-permeable
  • Ribosomes: Site of protein synthesis
  • Chloroplasts: Absorb light energy for photosynthesis
  • Permanent vacuole: Keeps the cell turgid
  • Cell wall: Made from cellulose, provides strength and support
• What 3 parts of a cell are only found in plant cells


  Chloroplasts, permanent vacuole and cell wall
• What is a specialised cell


  it’s a cell with a specific adaptation in order to do a specific function
• What is a stem cell


  it’s a unspecialised cell in which specialised cells come from
• How does a stem cell turn into a specialised cell


  Through differentiation
• What is the primary function of red blood cells?


  To carry oxygen around the body
• Why do red blood cells lack a nucleus?


  To provide more room to hold oxygen
• How does the structure of red blood cells facilitate oxygen transport?


  Their biconcave shape increases surface area for oxygen diffusion
• What is the function of dendrites in nerve cells?


  To form connections with other cells
• Why is the long shape of nerve cells important?


  It allows transmission of nerve impulses over long distances
• What is the role of mitochondria in sperm cells?


  To release energy for swimming
• What is the function of the head of a sperm cell?


  It contains enzymes to digest the egg cell membrane
• What is the primary function of muscle cells?


  To contract and support body movement
• How do muscle cells generate energy?


  They contain many mitochondria to release energy
• What allows muscle cells to contract?


  Protein filaments that slide over each other
• What is the function of white blood cells?


  To make antibodies to fight pathogens
• Why do white blood cells have a flexible shape?


  To engulf pathogens
• What is the function of ciliated epithelial cells?


  To trap bacteria and dust in the airway
• How do root hair cells absorb water?


  By osmosis and active transport of minerals
• What adaptation do root hair cells have for efficient absorption?


  A large surface area to absorb more water and minerals
• What is the primary function of palisade cells in plants?


  To perform photosynthesis efficiently
• Why are palisade cells packed with chloroplasts?


  To absorb energy from the sun for photosynthesis
• What is the function of xylem cells?


  To transport water and minerals from roots to leaves
• How are xylem cells adapted for their function?


  They are hollow tubes strengthened by lignin
• What is the function of phloem cells?


  To transport sugars throughout the plant
• How do companion cells assist phloem cells?


  They provide energy for the transport of sugars
• What are the adaptations of specialized cells in the human body?

  • Red blood cells: No nucleus, biconcave shape for oxygen transport
  • Nerve cells: Long shape, many dendrites for impulse transmission
  • Sperm cells: Tail for swimming, enzymes in head for fertilization
  • Muscle cells: Many mitochondria for energy, protein filaments for contraction
  • White blood cells: Flexible shape for engulfing pathogens
  • Ciliated epithelial cells: Cilia for trapping dust and bacteria
• What are the adaptations of specialized plant cells?

  • Root hair cells: Large surface area for water and mineral absorption
  • Palisade cells: Packed with chloroplasts for efficient photosynthesis
  • Xylem cells: Hollow tubes strengthened by lignin for water transport
  • Phloem cells: Transport sugars, assisted by companion cells for energy