Answer: "To move substances against a concentration or electrochemical gradient, a cell must use energy. Active transport mechanisms do just this, expending energy (often in the form of ATP) to maintain the right concentrations of ions and molecules in living cells."
Four chambered heart keeps oxygenated and deoxygenated blood separate and has double circulation while three chambered heart has a single circulation. Two chambered heart only has single atrium and single ventricle
Amino acids are used in the production of proteins!
There are two approaches used when inserting a pacemaker; the epicardial approach and the transvenous approach. Epicardial approach involves the opening the chest cavity and placing a lead on epicardial sac of heart while the transvenous approach involves accessing a vein and inserting an electrode into the vein. Epicardial approach for inserting pacemakers are divided based on approach to heart thoracotomy, upper abdominal or endoscopic.
Spongy bones forms the interior of the epiphyses, the diaphysis consist of compact bone surround the central marrow cavity.
