Best Answer: The definitions will tell you the differences. The nucleus, in a eukaryotic cell, contains the DNA for cell function and, therefore, is the control center of the cell (It is NOT a brain).It also contains the nucleolus which is the site where ribosomes are manufactured.he nucleus, in a eukaryotic cell, contains the DNA for cell function and, therefore, is the control center of the cell (It is NOT a brain). It also contains the nucleolus which is the site where ribosomes are manufactured.
The heart contains four chambers. The two upper chambers are the atria and the two lower chambers are the ventricles. On the cranial surface of each atrium is a pouch-like appendage called an auricle which is thought to increase the capacity of the atrium slightly.
The 2 upper chambers of the heart, also called the receiving chambers because blood enters the heart through veins that open into these upper cavities. Ventricle. The 2 lower chambers of the heart, also called discharging chambers because blood is pumped from the heart into arteries that exit from the lower cavities. Myocardium. The wall of each heart chamber is composed of cardiac muscle tissue.