Natural gas is a fossil fuel used as a source of energy for heating, cooking, and electricity generation. It is also used as fuel for vehicles and as a chemical feedstock in the manufacture of plastics and other commercially important organic chemicals. Fossil fuel based natural gas is a non-renewable resource.
Definition: A chromosome is a long, stringy aggregate of genes that carries heredity information and is formed from condensed chromatin. Chromatin is composed of DNA and proteins that are tightly packed together to form chromatin fibers. Condensed chromatin fibers form chromosomes.
The chrosomsomes have already duplicated but are still in the form of loosely packed chromatin fibers. PROPHASE: During the prophase the nucleoli in the nucleus disappear. The chromatin fibers become tightly ccoiled and condense into chromosomes. Chromosomes line up in pairs and are joined at the centromere. In the cytoplasm, the spindle fibers begin to form and are made of microtubules.