Mitochondrial research expanded in the late twentieth century after the invention of the electron microscope, and with the development of molecular genetic techniques, such as DNA sequencing and the use of enzymes that cut DNA at certain sites, called restriction endonuclease enzymes.ithin each mitochondrion is the mitochondrial DNA (mtDNA), which is different from the DNA in the cell's nucleus (nDNA). Organisms inherit their mitochondria only from their mothers via egg cells (oocytes).
Splenomegaly is a term which refers to enlargement of the spleen. The normal adult splenic length upper limit is usually around 12-15 cm.he causes of splenomegaly are protean, and can be thought of under a number of headings: 1  haematological disease. 2  haemodynamic. 3  infectious. 4  storage diseases/metabolic diseases. 5  neoplastic (non-haematologic).
1 Splenomegaly refers strictly to spleen enlargement, and is distinct from hypersplenism, which connotes overactive function by a spleen of any size.2  Splenomegaly and hypersplenism should not be confused.3  Each may be found separately, or they may coexist. Moderate splenomegaly, if the largest dimension is between 11â20 cm. 2  Severe splenomegaly, if the largest dimension is greater than 20 cm. 3  Splenomegaly refers strictly to spleen enlargement, and is distinct from hypersplenism, which connotes overactive function by a spleen of any size.