Critical: After seeds germinate, they must be removed from the heating mat. Germinate warm; grow cool. You are able to see how both of these varieties of tomatoes contain the similar cotyledons, but after their accurate leaves arise, 1 seedling has the serrated edges standard of a regular tomato leaf https://www.pentaverge.com/wall/blogs/29738/Germination-of-Seeds-A-Comprehensive-Guide