A level Biology Pre-Enrolment Task on Cell Structure Looking at Cells Cells are very small. Most are too small to be seen with the naked eye, and certainly not in any detail. In order to investigate cells, we need to be able to produce images that are both enlarged and more detailed. The first light microscope was developed by Robert Hooke in the 1660s, since then light microscopes have improved and electron microscopes have been developed. This has allowed scientists to study cells in detail.
Organelles and Ultrastructure When you look at a cell under the light microscope, the most obvious feature you will see is the very large nucleus. You may also see other structures, such as chloroplasts and large vacuoles in plant cells. These structures are organelles. Using an electron microscope, it is possible to identify a range of organelles in plant and animal cells. The detail of the inside of cells, as revealed by the electron microscope, is termed the cell’s ultrastructure (sometimes also called the fine structure).
Your pre-enrolment tasks As preparation for the A level Biology course, you need to write a report on the Ultrastructure of plant and animal cells as seen by an electron microscope. You need to include:
A large labelled diagram showing the ultrastructure of a Eukaryotic cell Details about the following organelles: o Nucleus, Endoplasmic Reticulum (Rough and Smooth), o Golgi Apparatus (sometimes called Golgi Body), Mitochondria, o Plasma (cell surface) Membrane, Cell Wall, Chloroplast, o Large Permanent Vacuole and Centrioles.
For each organelle we want you to include a labelled hand-drawn sketch in pencil, a description of their structure and an outline of their function. Finally, we would like you to outline how these organelles work together to produce and then secrete a protein out of the cell.
Suggested sources: www.s-cool.co.uk ; www.youtube.com/watch?v=ostQCAeUJSQ To be successful in A level Biology it is essential that you have a firm foundation of Biological knowledge for further study. Therefore you will be tested during the first week of the AS Biology course on your knowledge covered in B1 and B2 at GCSE. You should use your class notes and revision websites such as BBC Bitesize to prepare for this.