What do glaciers leave behind when they retreat

How many trophic levels are there in the following food chain? phytoplankton - shrimp - perch - pike - osprey

Students commonly confuse saccharomyces cerevisiae and staphylococcus aureus when viewed on a microscope slide how could you microscopically differentiate

In trying to determine whether dna or protein is the genetic material, hershey and chase made use of which of the following facts? a) dna contains sulfur, whereas protein does not. b) dna contains phosphorus, whereas protein does not. c) dna contains nitrogen, whereas protein does not. d) dna contains purines, whereas protein includes pyrimidines.