First-degree burns affect the outer layer of skin, which is called the epidermis. They are moist, red in color and cause pain, redness and swelling. First-degree burns are partial-thickness burns because of their depth. They will heal spontaneously.
Nucleus. DNA can be found inside the nucleus of every cell, apart from red blood cells. It's tightly wound and spread throughout the 46 chromosomes. One set of 23 chromosomes is inherited from each parent. Inside the chromosomes the DNA exists as genes.
Before a cell divides it has to replicate its DNA so that the daughter cell receives a copy of the genome. The DNA helix consists of two complementary DNA strands. Therefore, each of the two strands serves as a template for the construction of the other strand. Under normal conditions the DNA is packed into a compact structure called chromatin. To be able to replicate, the cell has to unfold and unwind the DNA, and also has to separate the two strands from each other.