An organelle is a specialized cellular structure in eukaryotic cells analogous to an organ in the body.Organelles are discrete structures within the cell that perform a specialized function. Most are surrounded by internal membranes and can be seen in the light or the electron microscope.n organelle is a specialized cellular structure in eukaryotic cells analogous to an organ in the body.
irregular pulse or heart palpitations; chest pain; pale skin; sweating; What causes abnormal heart rhythms? A number of things may cause an abnormal heartbeat, including high blood pressure. Other common causes are: Coronary heart disease. This serious heart problem occurs when cholesterol and other deposits block the coronary arteries. Medications
Arrhythmias may be caused by many different factors, including: 1  Coronary artery disease. 2  Electrolyte imbalances in your blood (such as sodium or potassium). 3  Changes in your heart muscle.  Injury from a heart 1  attack. Healing process after heart surgery.  Irregular heart rhythms can also occur in normal, healthy hearts.