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.
Heart is the most important organ of the human body. It lies in the thoracic cavity. It is divided into four chambers, two atria and two ventricles. Upper left chamber is called as the left atrium; lower left chamber is the left ventricle. Upper right chamber is called right atrium and lower right chamber is the right ventricle. Atria receive blood, whereas ventricles pump blood to the body.