(a)Levels of organisation, (b) Cell structure

• • Cells in complex multicellular organisms are specialised to carry out particular functions
• • Specialised cells form tissues
• • Tissues form organs
• • Organs form organ systems
• Levels of organisation in order

  A) organelles

  B) cells

  C) tissues

  D) organs

  E) organ systems

  
• What is the function of the nucleus?

  Answer:

  
• What is the function of the cytoplasm?

  Answer:

  
• What is the function of the cell membrane?


  Answer:

  
• What is the function of the chloroplasts?

  Answer:

  
• What is the function of the mitochondria?

  Answer:

  
• What is the function of the ribosomes?

  Answer:

  
• What is the function of the vesicles?

  Used to safely transport substances from one part of the cell to another
• Even a small difference in the amino acid sequence leads to the formation of a completely different protein
• The sequences of amino acids cause polypeptide chains to fold in different ways, giving rise to the diverse shapes of proteins
• Every protein has a unique 3-D shape that allows it to carry out its specific function
• The shape of a protein is crucial in determining its function
• Enzymes have a specifically shaped active site where a specific substrate molecule fits for a reaction to occur
• If the shape of the active site does not match the shape of the molecule, the reaction will not take place
• Antibodies, produced by certain white blood cells, attach to antigens on pathogens
• The shape of the antibody must match the shape of the antigen for attachment and signaling for destruction