Specification: 1.2.1 Exchange Surfaces and Breathing

Specification: 1.1.3 Cell Division, Cell Diversity and Cellular Organisation

- state that mitosis occupies only a small percentage of the cell cycle and that the remaining 
   percentage includes the copying and checking of genetic information;
- describe, with the aid of diagrams and photographs, the main stages of mitosis:
      - behaviour of the chromosomes
      - nuclear envelope
      - cell membrane 
      - centrioles
- explain the meaning of the term homologous pair of chromosomes
- explain the significance of mitosis for growth, repair and asexual reproduction in plants and 
animals
- outline, with the aid of diagrams and photographs, the process of cell division by budding in yeast
- state that cells produced as a result of meiosis are not genetically identical (details of 
   meiosis are not required)
- define the term stem cell
- define the term differentiation, with reference to the production of erythrocytes (red blood 
   cells) and neutrophils derived from stem cells in bone marrow, and the production of xylem 
   vessels and phloem sieve tubes from cambium
- describe and explain, with the aid of diagrams and photographs, how cells of multicellular 
   organisms are specialised for particular functions, with reference to:
      - erythrocytes
      - neutrophils
      - epithelial cells
      - sperm cells
      - palisade cells
      - root hair cells
      - guard cells 
- explain the meaning of the terms tissue, organ and organ system; 
- explain, with the aid of diagrams and photographs, how cells are organised into tissues, 
   using squamous and ciliated epithelia, xylem and phloem as examples; 
- discuss the importance of cooperation between cells, tissues, organs and organ systems

Specification: 1.1.2 Cell Membranes

- outline the roles of membranes within cells and at the surface of cells; 
- state that plasma (cell surface) membranes are partially permeable barriers; 
- describe, with the aid of diagrams, the fluid mosaic model of membrane structure  
- describe the roles of the components of the cell membrane;
      - phospholipids
      - cholesterol
      - glycolipids
      - proteins
      - glycoproteins
- outline the effect of changing temperature on membrane structure and permeability; 
- explain the term cell signaling; 
- explain the role of membrane-bound receptors as sites where hormones and drugs can 
   bind; 
- explain what is meant by:
      - passive transport (diffusion and facilitated diffusion including the role of membrane proteins)
      - active transport
      - endocytosis
      - exocytosis;
- explain what is meant by osmosis, in terms of water potential. (No calculations of water potential will be required); 
- recognise and explain the effects that solutions of different water potentials can have upon plant and animal cells

Specification: 1.1.1 Cell Structure

- state the resolution and magnification that can be achieved by a light microscope, a 
   transmission electron microscope and a scanning electron microscope
- explain the difference between magnification and resolution
- explain the need for staining samples for use in light microscopy and electron microscopy
- calculate the linear magnification of an image
- describe and interpret drawings and photographs of eukaryotic cells as seen under an 
   electron microscope and be able to recognise the following structures
      - nucleus
      - nucleolus
      - nuclear envelope
      - rough and smooth endoplasmic reticulum
      - golgi apparatus
      - ribosomes
      - mitochondria
      - lysosomes
      - chloroplasts
      - plasma membrane
      - centrioles
      - flagella
      - cilia
            - outline the functions of the structures listed above
- outline the interrelationship between the organelles involved in the production and 
   secretion of proteins
- explain the importance of the cytoskeleton in providing mechanical strength to cells, aiding 
   transport within cells and enabling cell movement
- compare and contrast, with the aid of diagrams and electron micrographs, the structure of 
   prokaryotic cells and eukaryotic cells
- compare and contrast, with the aid of diagrams and electron micrographs, the structure 
   and ultrastructure of plant cells and animal cells