In the LAB 0.0 / 5 ? BiologyGeneticsUniversityNone Created by: exam yesCreated on: 15-01-19 14:18 What colour is a gram negative bacteria colony?and what colour is positive? Red / Pink is negative and purple is positive 1 of 11 What does the catalase test, test for and how? The presence of the enzyme catalase which breaks down hydrogen peroxide 2 of 11 Why are many of the colour settle plates coloured? The different colours abosrb UV light as protection 3 of 11 In a spore stain what is the colour of the vegetative cell and what is a vegetative cell? The vegetative cell actively grows and divides and shows up as red? when it is stained 4 of 11 Why is it necessary to dry cells in air before heat fixing? What would happen if they werent dry? When dried the cells flatten out by being dehydrated, if they were heated straight away the cells would be boiled off by the hot flame 5 of 11 What is an example of a bacillus bacteriam i.e rod shaped? E.Coli 6 of 11 What is an example of a cocci - circular - shaped bacterium? Pseudomonas and coccus bacteria 7 of 11 Why are gram negative bacteria pink / red in colour? The cell walls dont retain the crystal violet stain 8 of 11 Describe the cell wall and membrane arrangement of a gram negative bacteria Have a thin peptidoglycan cell wall, is surrounded by another outer membrane with a plasma membrane 9 of 11 What are the two main componensts of purple gram positive bacterial cell walls? Has a thick peptidoglycan wall and contains teichoic acids 10 of 11 What is the bradford reagent used for? Determining protein concentration 11 of 11
Comments
No comments have yet been made