Cell structure: eukaryotic organelles
Every plant and animal is built from eukaryotic cells, and inside each cell is a busy set of tiny working parts called organelles. In this lesson we go inside the cell as the electron microscope reveals it and meet each organelle in turn - the cell surface membrane, the nucleus with its envelope and nucleolus, mitochondria, ribosomes (80S and 70S), the rough and smooth endoplasmic reticulum, the Golgi body and lysosomes - learning to recognise each one and to outline exactly what it does. We add the parts special to plant cells (the cellulose cell wall, chloroplasts, the large permanent vacuole and tonoplast, and plasmodesmata) and the parts special to animal cells (centrioles, cilia and microvilli). We compare a typical plant palisade cell with a typical animal liver cell, learn to draw low-power plan diagrams of a stem, root or leaf, and finish with how to make a temporary wet mount and draw cells under a light microscope.
By the end you should be able to (NSSCAS Biology (AS) 2.2a):
- Identify and recognise the following parts of a eukaryotic cell and outline the functions of the: cell surface membrane; nucleus, nuclear envelope and nucleolus; mitochondrion; ribosomes (80S in the cytoplasm and 70S in chloroplasts and mitochondria); chloroplast; rough and smooth endoplasmic reticulum; Golgi body (Golgi apparatus or Golgi complex); lysosomes; cell wall; centrioles; cilia; microvilli; plasmodesmata; large permanent vacuoles and tonoplast
- Describe and interpret the structure of plant and animal cells as seen with an electron microscope
- Draw and label low power plan diagrams of tissues and organs (including a transverse section of stems, roots and leaves)
- Compare the structure of a typical plant (palisade) and animal (liver) cells
- Make temporary slides (wet mounts) of plant and animal cells (e.g. epidermal cells from a leaf or an onion, epithelial cells from the trachea of a sheep or human cheek cells)
- Make observations and drawings of cells as seen under a light microscope (including cells within transverse sections of stems, roots and leaves)
Miss Rachel and Mike talk through the whole topic — with the figure and working drawn live.