DNA is generally tightly packed into a structure called chromatin. It is double stranded and twisted into a structure called a double helix. In order to replicate, DNA must unwind. After unwinding, each side of DNA separates by unzipping down the middle, with the two unzipped strands serving as templates for creating new strands. At the end of replication, the two new segments of DNA each contain one old and one new strand.
Replication occurs at different rates in different types of cells. Some cells continuously divide and must constantly replicate their DNA. Other cells divide at a much slower rate and do not need to replicate their DNA as often. Some cells divide until the organ they make up reaches its normal size, and then they do not divide again.
DNA stands for deoxyribonucleic acid. Each strand of DNA is made up of a sugar, a phosphate and a nitrogenous base bonded together into a structure called a nucleotide. Many nucleotides bond together to form DNA.
<span>DNA replication of one helix of DNA results in two identical helices. If the original DNA helix is called the "parental" DNA, the two resulting helices can be called "daughter" helices. Each of these two daughter helices is a nearly exact copy of the parental helix (it is not 100% the same due to mutations). DNA creates "daughters" by using the parental strands of DNA as a template or guide. Each newly synthesized strand of DNA (daughter strand) is made by the addition of a nucleotide that is complementary to the parent strand of DNA. In this way, DNA replication is semi-conservative, meaning that one parent strand is always passed on to the daughter helix of DNA.</span>
The most widely accepted theory of planetary formation, known as the nebular hypothesis, maintains that 4.6 billion years ago, the Solar System formed from the gravitational collapse of a giant molecular cloud which was light years across. Several stars, including the Sun, formed within the collapsing cloud.
A nurse suspects that the IV line through which Doxorubicin (adriamycin) is infusing has infiltrated. The nurse has discontinued the IV site. The nurse should IMMEDIATELY APPLY ICE PACK TO THAT AREA. Ice pack helps to reduce the absorption of the drug doxorubicin and thus minimize the its effect.
Plate tectonics have the potential to affect organic evolution due to the fact that the movement of these plates may well cause land masses to shift and cause a change in climate as a result
Each "human body cell" has 46 chromosomes. But human sex cells have 23 unpaired chromosomes in each cell. Sex cells are created by a special type of cell division, Meiosis.
