Because it has no scientific explanation. As a matter of fact it has no explanation.
The things that black cats cause bad luck are a myth, and do not have any proof or explanation, meaning it cannot be concluded neither as a hypothesis nor scientific.
Hope it helped,
BioTeacher101
 
        
             
        
        
        
It's a region of DNA that binds DNA Polymerase to begin replication.
        
             
        
        
        
The Cell<span> membrane </span>surrounds<span> all living </span>cells<span> and is the most important organelle, there is also a similar plasma membrane that </span>surrounds<span> all the organelles except for the ribosome. It is composed of phospholipids, proteins, and carbohydrates, which are arranged in a fluid mosaic structure.</span>
        
                    
             
        
        
        
Show differences between species/organisms