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 Heart. Structure. The heart is divided into four chambers: the right atrium and right ventricle, and the left atrium and left ventricle. The walls of the chambers are made of a special muscle, the myocardium, which contracts rhythmically under the stimulation of electrical currents.