Erwin Chagraff did further observation on the Double Helix DNA. He concluded that there is a 1:1 ratio of guanine and cytosine and the same for adenine and thymine.
A base pair is two nucleobases combined through a double hydrogen bond. This creates a double helix in DNA. Adenine can only bond with Thymine and Guanine is only compatible with cytosine.
Almost everyone on earth has 46 chromosomes. 23 from each parent. Chromosome carry your characteristics that make you, you. Chromosomes are threadlike structures of nucleic acid found in the nucleus of most living cell. A picture of all the chromosomes in one cell is called a Karyotpe.
In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. This process occurs in all living organisms and is the basis for biological inheritance. DNA is made up of a double helix of two complementary strands. During replication, these strands are separated. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, a process referred to as semiconservative replication. Cellular proofreading and error-checking mechanisms ensure near perfect fidelity for DNA replication.
In a cell, DNA replication begins at specific locations, or origins of replication, in the genome. Unwinding of DNA at the origin and synthesis of new strands results in replication forks growing bi-directionally from the origin. A number of proteins are associated with the replication fork to help in the initiation and continuation of DNA synthesis. Most prominently, DNA polymerase synthesizes the new strands by adding nucleotides that complement each (template) strand. DNA replication occurs during the S-stage of interphase.
DNA damage is an alteration in the chemical structure of DNA. Damage that occurs to DNA can occur hydrolytic and metabolic processes.