Why are certain amino acids called essential amino acids

1. key concept list themajor biomes, and give onecharacteristic feature of each.

Which direction does the energy flow in this energy pyramid ?

Cpr, or cardiopulmonary resuscitation, is a first-aid technique to save lives. it involves compressions of the patient's chest cavity. which description is the best description of the functions of chest compressions in cpr? chest compressions are done to pump the heart. chest compressions are done to strengthen the rib bones. chest compressions increase carbon dioxide inhalation. chest compressions allow the patient's muscles to wake up.