Answer:
Because the trophozoites are unable to survive outside a host.
Explanation:
The term infectious is used for a disease or microorganism that can be transmitted from one organism to the other organism through the environment. If we look at the two forms of Giardia, we find that out of the two forms viz. cysts and trophozoites, only the cysts of Giardia have the ability to remain alive in the environment outside the host and thus they are able to be transmitted to the other organisms. On the other hand trophozoites are not able to survive in outside environment so there is no chance of transmission of trophozoites.
 
        
             
        
        
        
I think ur face is a rat and gorilla I eat humans oh yeaa so don’t oh yeaaa
        
             
        
        
        
The property of carbon that allows it to make very large organic molecules would be the ability of carbon to form a maximum of 4 covalent bonds. Due to its 4 valence or outermost electrons.
        
             
        
        
        
Answer:
a chemical reaction mass is neither created nor destroyed
Explanation:
a chemical reaction mass is neither created nor destroyed