<span>The sequence of alternation of generation is; gametes->zygote->sporophyte->spores->gametophyte->gametes.
The attached diagram shows clearly this looped cycle. Alternation of generation
occurs in a more advanced land plant that
has distinct
haploid and diploid phases in their life
cycle. The diploid phase usually involves
the sporophyte while the haploid phase involves the gametophyte</span>
        
             
        
        
        
A pathogen is a disease carrying vector that has the ability to spread using a variety of different mechanisms. A pathogen that is a contagion has the ability to spread through touch. An example of such a pathogen would be the one that results in staph infections.