DNA replication,illustration. Strand of DNA (deoxyribonucleic acid) splitting (centre left) and forming two identical copies (right). DNA consists of two strands (blue) of sugar phosphates forming a double helix (spiral). The two strands are held together by bonds between their nucleotide bases (coloured bars). There are four nucleotide bases,but they pair in only two combinations (here,pink-yellow and green-orange): guanine to cytosine,and thymine to adenine. Hence each DNA strand is a complementary copy of the other. As the original strand splits,this complementary base chemistry causes a reverse copy to assemble next to each half,reforming the original DNA strand. This is known as semi-conservative replication. The nucleotide base sequence is the genetic code. DNA,which is stored in cell nuclei,is the genetic material that controls the growth and development of all living organisms. | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Jensen, Mikkel Juul |
Bildgröße: | 8048 px × 4343 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |