Answer:
The correct answer is The drug binds to the 30S small ribosomal  subunit eukaryotes have 40S small sub unit.
Explanation:
Tetracycline belongs to broad spectrum antibiotic.Tetracycline is named so because it contain a derivative of four hydrocarbon rings.
  Tetracycline act by inhibiting the protein synthesis process in prokatotes by binding to the small ribosomal subunit also called 30S subsunit and blocks the binding of amino acyl tRNA to the A site or attachment site of ribosome.
  As eukaryotes contain 40S ribosomal  subunit,it becomes difficult for tetracycline to bind with 40S ribosomal subunit of eukaryotes.
  
 
        
             
        
        
        
D. Cholinergic antagonists
 
        
             
        
        
        
Answer:
An example of mutualism is the relationship between remora and shark. 
Explanation:
Remora depends on sharks for food and locomotion. It has a sucking mouth that helps it to attach itself to the shark.
 
        
             
        
        
        
Answer:
 The mitochondria is the powerhouse of the cell
 
        
             
        
        
        
So that it can sustain different life that requires different environments. Angler fish, for example, require a dark and cold environment to thrive while tuna require a light and warm environment.