Look at sucrose, a disaccharide, and cellulose, a polysaccharide, on the carbohydrate page. How do you think these two molecules were formed? help please

Use the phylogenetic tree to the right to determine which statement below is true. organisms a and f are not related. organism e is more closely related to organism b than organism f. organisms c and d are more closely related than organisms a and b. phylogenetic trees

Wich level of organization includes all the other levels or organizations

Which of the following is a reason why early living organisms on earth could not have survived on the surface? 1. the lack of an ozone layer 2. the lack of oxygen in the atmosphere 3. the fact that these organisms were single-celled