Alexander Fleming discovered penicillin, C16H18N2O4S, in 1928 at the University of London. He isolated the compounds from a mold which had contaminated some of his experiments. Since then penicillin has been used as a general antibiotic since it destroys bacterial cells without harming animal cells. How many moles of penicillin molecules are present in 250 mg penicillin

An easy way to calculate the amount of energy available at each level is to what?

Directions: read the descriptions of the four islands presented in the lesson. 1. list two new traits that each new species of rat might demonstrate as it adapts to the conditions on each island. 2. introduce one of the four new rat species to another island and describe one challenge it would encounter and one success as it adapts to its new environment.

Cladistics is a way of classifying organisms by examining the characteristics of their ancestors and descendants and depicting the relationships in a cladogram. which of the following best describes a challenge in classifying organisms this way? a. there are millions of species on earth, and a cladogram is not a practical means for classifying all of them. b. it is impossible to tell which organisms are most closely related to each other using a cladogram. c. cladograms are detail-oriented and do not provide a useful understanding of evolutionary relationships. d. there is a limited number of ways to organize the information, so most cladograms end up looking very similar.