Answer:
1. A natural killer cell identifies unusual cells, combines with them, and discharges perforin and molecules of granzyme that stimulates apoptosis.  
2. A basophil comprises huge concentrations of histamine in granules, gets stain with basic dye methylene blue, and helps in inflammation and allergic reactions.  
3. A macrophage refers to a huge agranular phagocyte, which is found within the tissues like lungs and brain.  
4. An eosinophil comprises histamine and major basic protein in granules gets stain with acidic dye eosin and helps in reactions against the helminths and protozoa.  
 
        
             
        
        
        
He used Selective Breeding
        
             
        
        
        
Answer:
Acidophilic and acidotolerant eukaryotic microorganisms such as algae, amoebas, ciliates, heliozoan and rotifers, not to mention filamentous fungi and yeasts.
Explanation:
Acidophilic and acidotolerant eukaryotic microorganisms such as algae, amoebas, ciliates, heliozoan and rotifers are the organisms which can survive in highly acidic solution that have large amounts of iron, sulfur dioxide, carbondioxide, and oxygen molecule. In these organisms algae is autotrophic whereas archaea, bacteria, fungi, yeasts and protozoa are heterotrophic.
 
        
                    
             
        
        
        
A gemstone is a piece of hard mineral that is considered exquisite in terms of physical properties and valuable because of its rarity or usefulness. In this case, the properties classify diamond as a gemstone is its <span>color and profitability. Diamonds are very expensive because of its rarity</span>