4. Which part of DNA provides instructions for how to produce a protein?
A. The sequence of nitrogen bases
B. The sugar molecules
C. The phosphate groups
D. The bonds that hold the sugar and bases together

Q: a: in sexually reproducing animals, once fertilization of the egg takes place, the exists as a single cell until cell division begins

Identify two examples of chemical reactions that you have encountered during the last week. identify an exothermic and endothermic reaction. explain.

Land conservation is a worldwide priority. there are several methods to prevent the loss of land due to a variety of reasons. which method is not a way to conserve land? a) sea walls b) rainwater harvesting c) limits on clear cuts of forests d) cut and burn methods of clearing land