A. the cell theory stating that all living things are composed of cells.
Hope this helps!
-Payshence
 
        
             
        
        
        
It will probably take the highest roll in the food chain which then factors to the other animals either dying, or competing for resources. making the ecosystem unstable.
 
        
             
        
        
        
Answer:
IGCSE**
u can just go through the book
 
        
             
        
        
        
Based on the CDC guidelines a person with a CD4+ cell count between 200-400 is regarded as being in <u>the second stage</u> of the HIV infection. 
Acquired Immunodeficiency Syndrome 
Acquired immunodeficiency syndrome (AIDS) is a condition caused by HIV (human immunodeficiency virus). AIDS is a chronic disorder and can become life-threatening for the infected person. The HIV viruses reproduce inside the host and while doing so they destroy the CD4+ immune cells which reduce the person's ability to fight against other diseases. 
CD4+ cell count and AIDS
According to the CDC (U.S. Centers for Disease Control and Prevention), HIV infection is categorized into different stages based on the number of CD4+ cells. 
- Stage 1: - CD4+ cell count is more than 500 per microlitre. There are no symptoms or AIDS-related conditions. 
- Stage 2: - CD4+ cell count is more than 500 per microlitre. There are no symptoms or AIDS-related conditions.
- Stage 3: - The CD4+ cell count falls below 200 and AIDS-related symptoms and conditions are present.  
Learn more about HIV infection here:
brainly.com/question/13662165
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