Question

1. What are the three domains?

2. What is meant by colony morphology?

3. What are the three shapes of bacteria mentioned in the lab notebook?

4. What is a zoonotic disease?

1. Give an example of a zoonotic disease.

5. Does cyanobacteria have chloroplasts?

1. If not how do they perform photosynthesis?

6. What does it mean that bacteria are saprotrophic?

Tell me about gram staining.

7. What information do you get from gram staining?

8. Why do some bacteria stain purple and some pink?

Answer 1

1 The three domain system of classification of organism was proposed by Carl woese in 1990.It mainly consisted of three domains -1 Archaea 2 Bacteria 3 Eukaryote

2 Colony morphology is defined as a method that is used to describe the characteristics of individual colony of bacteria growing on agar in a petri dish .This morphology is used to identify certain colony forming organisms.

3 The three shapes of bacteria are Coccus,Bacillus,Spiral.Coccus are round or circular in shape ,Bacillus are rod shaped ,and Spiral are spiraling in structure.

4 A zoonotic disease can be defined as any disease or infection that is naturally transmissible from vertebrate animals to humans .Examples include Salmonellosis,plague,Coronavirus,Rabies etc

5 Example of zoonotic disease include Zoonotic influenza ,Plague,Rabies,Coronaviruses,Brucellosis

6 No cyanoblast do not have a membrane bound chloroplast as seen in plants .

7 The Cyanobacteria photosynthesize with the help of Thylakoids which are flattened sacs which are able to convert suns energy and absorb carbon dioxide and release oxygen .

8 Saprotrophs are the organism that obtain their nutrition from dead and decaying organic matter .They secrete their digestive enzymes onto such dead decaying organisms so as to dissolve it and then absorb nutrient from it. Examples include mushroom , fungi

9 The gram staining is a type of staining reaction used to classify bacteria into two groups Gram positive and Gram negative.And by using this staining method we can identify the type of bacteria and shape of bacteria .

10 The bacteria that stain purple are gram positive and they retain the primary staining by crystal violet .Whereas the bacteria that appear pink are Gram negative as they lose the primary staining by crystal violet and get stained by the secondary stain Safranin and thus appear pink.