40 likes | 173 Views
1) The ultra structures of microorganisms can only be observed by using transmission electron microscopy (TEM). i . Explain why those structures cannot be seen under light microscopy. ii. State the advantages of TEM [ 20 marks/ markah ] .
E N D
1) The ultra structures of microorganisms can only be observed by using transmission electron microscopy (TEM). i. Explain why those structures cannot be seen under light microscopy. ii. State the advantages of TEM [20 marks/markah]
2) After a process of simple staining, a microbiologist observed the specimen under compound microscope and sees nothing. i. What is probable step that the microbiologist has missed and why the procedure is important. ii. Suggest what steps shall be include if the microbiologist want to change the procedure using differential staining. [30 marks/markah]
3) You are given a strain of bacteria which is expected to fall under genera Bacillus based on morphology identification. One important features of Bacillus is it have endospores. i. Write a procedure to prepare the specimen for special staining starting from pretreatment so that it can be prove as Bacillus by identification under compound light microscope.[20Marks/Markah] ii. Explain why do you need to do the pretreatment before staining? [5 Marks/Markah]
Light microscope limits the detailed studies of viruses and internal structure of microorganisms. This problem had lead the scientist to invent electron microscope. • Explain THREE (3) important characteristics of scanning electron microscope (SEM). [15 Marks/Markah] ii. Write a procedure on how to stain a specimen for viewing under scanning electron microscope (SEM). [10 Marks/Markah]