About Tac Light. Tac Light is a small-but-powerful flashlight by Bell & Howell that has been advertised on television in 2016. The official product website is trytaclight.com, which was registered in April 2016. The screenshot below was taken of the official website in May 2016. 22 times brighter than regular flashlights (600 lumens)
However, only four bases: A (adenine), C (cytosine), G (guanine), and T (thymine) constitute the backbone of the molecule. The DNA molecule is made up of two polynucleotide strands intertwined together to form a long helical structure, the DNA double helix.
Plants and Animals. In plants and animals DNA is also found in the cell nucleus. The DNA of all animals is very similar. The major differences are in the number of chromosomes and genes, and the arrangement of base pairs within these genes.