Embedded Files
RELEVANT LEARNING OUTCOME:
(d) Describe the structure of a typical bacterial cell (small and unicellular, peptidoglycan cell wall, circular DNA, 70S ribosomes and lack of membrane-bound organelles).
Bacterial cells are unicellular prokaryotic cells that range in length of 0.1 to 10 um, and that can be seen under a light microscope.
An interesting feature of the bacteria is the plasmid. It is an extrachromosomal circular DNA that is non-essential for survival but may confer advantageous traits such as antibiotic resistance.ย
A labelled diagram (a) and electron micrograph (b) of a bacterium.
๐๏ธโ๐จ๏ธ Watch this video that describes the structures of the bacteria.ย
How are they different from eukaryotic cells? How then do you think antibiotics work against bacteria?
Bacteria can be classified into two groups based on the external structure of cell. The method that is used to differentiate the two groups is called Gram staining.
๐๏ธโ๐จ๏ธ Watch this video that describes and explains this method of identifying bacteria.
[Note: The video mentions that the stain is trapped within the cell. However, the more recent understanding is that the stain is trapped in the peptidoglycan layer, as shown in your notes.]
Why do you think it is helpful to identify the type of bacteria in question? How would this affect the choice of antibiotic used in a treatment?
๐๏ธCheck Your Understanding: SLS Checkpoint
๐๏ธCheck Your Understanding: SLS Checkpoint
For more information on the bacterial cell, visit the following SLS Activity:
Bacteria H1/H2 (requires login).
๐ค Dropping some knowledge...
๐ค Dropping some knowledge...
If you'd like to find out more about how antibiotics work as a treatment against bacterial infections, check out this article:ย
'How do antibiotics work, and how does antibiotic resistance evolve?'
๐คWhy are antibiotics ineffective against viruses?
๐๏ธCheck Your Understanding
๐๏ธCheck Your Understanding
Attempt Qns 6 of the learning goals.
Content
Content
Page updated
Google Sites
Report abuse