Biology QuizTheLastDialogue BIOLOGY QUIZ Test Your Knowledge Of Biology With These Quizzes Biology Online Quiz for Kids and Adults #1. How Many insects Are There on Earth? Ten billion Ten trillion Ten million trillion 100 billion Work Harder #2. How many neurons are there in an average human brain? One billion 100 Trillion 100 billion 1000 million Work Harder Previous Finish Results Well Done. You Are Roaring Like A Lion Keep Working. Slow & Steady Wins The Race START NEW