Cells

• What is the function of a nucleus?

  Contains Genetic Information and controls the functions of the cell
• What is the function of a cell membrane?


  Controls what enters and leaves the cell
• What is the function of a cytoplasm?

  Where many cell activities and chemical reactions occur
• What is the function of a mitochondria?

  Provides energy from aerobic respiration
• What is the function of a ribsome?

  Makes protein synthesises
• What is the function of a chloroplast?


  Full of chlorophyll for absorbing sunlight to make photosynthesises
• What is the the function of a vacule?


  Used to store water and other chemicals as cell sap
• What is the function of a cell wall?

  Gives shape and support, made of cellulose
• This is a diagram of an animal cell and plant cell

  
• What is a sperm cell?

  Acrosome (head) contains enzyme to break into egg; tail to swim; Many mitochondria to provide energy to swim
• What is a nerve cell?


  Long to transmit electrical impulses over a distance.
• What is a muscle cell?

  Contain protein fibres that can contract when energy is available,

  making the cells shorter.
• What is a root hair cell?

  Long extension to increase surface area for water and mineral

  uptake; thin cell wall.
• What is a Xylem cell?

  Waterproofed cell wall; cells are hollow to allow water to move

  through.
• What is a Phloem cell?

  Some cells have lots of mitochondria for active transport; some

  cells have very little cytoplasm for sugars to move through easily.
• This is a root hair cell

  
• This is a nerve cell

  
• This is a sperm cell

  
• Cell wall (bacteria) gives shape and support which is not made of cellulose
• Plasmid DNA is loops of DNA that can be swapped between bacteria
• A sperm cell is used to carry the Father's genetic information to the egg
• Adaptation : Sperm cell

  • The small cytoplasm makes the head streamlined to reduced drag when moving
  • The acrosome contains digestive enzymes to break down the outer layers of the egg
  • The large nucleus contains Genetic information
  • The middle section contains lots of mitochondria where respiration take place to release energy needed for the flagellum to move
  • A long flagellum (tail) which whips from side to side to allow the sperm to move
• A red blood cell carries oxygen around the body
• Adaptation : Red blood cell

  • Biconcave shape gives a larger surface area to volume ratio to increase diffusion of oxygen in and out of the cell
  • Haemoglobin binds to oxygen to form oxy-haemoglobin so oxygen can be transported. In tissues, this reaction is reversed so oxygen is released
  • No nucleus to make more space for haemoglobin
• White blood cells destroy pathogens
• Adaptation : White blood cell

  • Lymphocytes makes and release antibodies which can destroy pathogens
  • Lymphocytes can also make antitoxins against any toxins made by pathogens
  • Phagocytes engulf ( surround ) and digest pathogens
• Adaptation : Root hair cell

  • Hair increase the surface area available for movement of water and minerals into the cell
  • Thin cell wall so there is less distance for substances to move over
  • Large permanent vacuole that speeds up movement of water by osmosis
  • Lots of mitochondria to provide energy needed for active transport of mineral ions
• Adaptation : Phloem

  • Cell walls between cells break down to form sieve plates. These allow dissolved food to move up freely up and down the tubes
  • Companion cells. Phloem are mostly empty cells (without many of their own organelles) so the companion cells help keep the phloem cells alive
  • Companion cells have a lot of mitochondria to provide energy which is transferred to phloem to help move food up and down the plant
• Palisade cells absorb light energy and carry out photosynthesis

  
• Adaptation : Palisade cell

  • Tall and thin so lots can be packed into a leaf and it gives a large surface area for absorbing light.
  • Lots of chloroplasts, filled with chlorophyll for absorbing light energy and carrying out photosynthesis
• What is a plant meristem?


  It is parts of a plant where growth occurs
• What's an interphase? (Mitosis)


  In an interphase the cell grows bigger and makes more organelles
• Mitosis is a type of cell division producing 2 genetically identical daughter cells, it is used to make new cells for growth and repair
• What is an eukaryotic?

  It is a cell with a nucleus
• What is a Prokaryotic?

  It is a cell without a nucleus
• What's an interphase? (mitosis)


  In an interphase the cell grows bigger and makes more organelles

  
• What happens in step one of mitosis?

  Before a cell can divide it needs to grow and increase the

  number of sub-cellular structures such as ribosomes and

  mitochondria. The DNA replicates to form two copies of each

  chromosome.
• What happens in step 2 of mitosis?

  The chromosomes are condensing – this means they are

  thickening.
• What is happening in step 3 of mitosis?

  The nucleus has been disassembled, chromosomes line up in

  the middle of the cell.
• What happens in step 4 of mitosis?

  In mitosis one set of chromosomes is pulled to each end of

  the cell and the nucleus divides.