Microbiology: Case Study Question

Hello,

This is the book I am using "Microbiology: An Introduction, 9th Edition Tortora "

I am currently taking microbiology and have a case study that I need some help with answer the question. I already have the first question answered however I need help with the rest. Please let me know if anyone can help 

A 7 year old girl is brought in to the doctor’s office by her mother.  Upon examination, the doctor notices that the girl has a fever, and a fine ‘sandpaper’-like rash. The girl states that, ‘…it’s hard to swallow, and my throat hurts.  My ears hurt too!”  The doctor is not surprised to find that the girl’s throat appears reddened, and her tongue is spotted and strawberry-like.  The doctor obtains a throat culture and sends the culture to you.

1.   When you receive the culture, you decide to gram stain this unknown organism. Please list the 4 steps of gram staining.

   1) Answered

2.  After gram staining, you find that the organism is ‘gram-positive.’  You next prepare a culture of the organism on blood agar.   When you inspect the culture, you find that a
‘clear ring’ has begun to form around each of the colonies.  What has caused this ring? How does this help you to identify this organism?  Please draw a picture depicting what you can see on your Petri plate.
 
3.  Based on the gram stain, and on the way the organism behaved on the culture media, what organisms could this be?  What is the basis for your conclusions?

4. Now let’s add the patient’s symptoms, and what the doctor observed.  Based on the little girl’s symptoms, what the doctor observed, the gram stain results, and the way the organism behaved on the culture media, what do you think this organism is?  How did you come to your conclusion?

5.  Now that you have reached your conclusion, you can go to the “Index” at the back of your text and see everything that the author’s have included about this organism.  After reviewing this information, please tell me what this organism has in its cell wall.  How does this help the organism?  Briefly describe how we gain immunity from this organism.