Normal heartbeat. Tachycardia is caused by something that disrupts the normal electrical impulses that control the rate of your heart's pumping action. Many things can cause or contribute to problems with the heart's electrical system.These factors include: 1  Damage to heart tissues from heart disease.2  Abnormal electrical pathways in the heart present at birth (congenital).n atrial flutter, the heart's atria beat very fast but at a regular rate. Atrial flutter is caused by irregular circuitry within the atria. The fast rate results in weak contractions of the atria. The rapid signals entering the AV node cause a rapid and sometimes irregular ventricular rate.
Definition: A diploid cell is a cell that contains two sets of chromosomes. One set of chromosomes is donated from each parent. Examples: The diploid number of a cell is the number of chromosomes in the cell. This number is commonly abbreviated as 2n, where n stands for the number of chromosomes.
Triploid and tetraploid chromosomes are examples of polyploidy. Polyploid cells and organisms are those containing more than two paired (homologous) sets of chromosomes. Most species whose cells have nuclei (Eukaryotes) are diploid, meaning they have two sets of chromosomesâone set inherited from each parent.However, polyploidy is found in some organisms and is especially common in plants.pecies whose cells do not have nuclei, that is, Prokaryotes, may be polyploid organisms, as seen in the large bacterium Epulopicium fishelsoni [1] . Hence ploidy is defined with respect to a cell. Most eukaryotes have diploid somatic cells, but produce haploid gametes (eggs and sperm) by meiosis.