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The two types of beta decay are known as beta minus and beta plus.In beta minus (β −) decay, a neutron is converted to a proton, and the process creates an electron and an electron antineutrino; while in beta plus (β +) decay, a proton is converted to a neutron and the process creates a positron and an electron neutrino. β + decay is also known as positron emission.
Following electron capture, the atomic number is reduced by one, the neutron number is increased by one, and there is no change in mass number. Simple electron capture by itself results in a neutral atom, since the loss of the electron in the electron shell is balanced by a loss of positive nuclear charge. However, a positive atomic ion may ...
Telomeres are regions of repetitive DNA close to the ends and help prevent loss of genes due to this shortening. Shortening of the telomeres is a normal process in somatic cells. This shortens the telomeres of the daughter DNA chromosome. As a result, cells can only divide a certain number of times before the DNA loss prevents further division.
However, it is noted that the specific sequence of intronic splicing elements and the number of nucleotides between the branchpoint and the nearest 3' acceptor site affect splice site selection. [ 8 ] [ 9 ] Also, point mutations in the underlying DNA or errors during transcription can activate a cryptic splice site in part of the transcript ...
(The first process can even precipitate the second one.) Like IC electrons, Auger electrons have a discrete energy, resulting in a sharp energy peak in the spectrum. Electron capture also involves an inner shell electron, which in this case is retained in the nucleus (changing the atomic number) and leaving the atom (not nucleus) in an excited ...
The other two types of decay are observed in all the elements. Lead, atomic number 82, is the heaviest element to have any isotopes stable (to the limit of measurement) to radioactive decay. Radioactive decay is seen in all isotopes of all elements of atomic number 83 or greater.
This type of DNA damage would not accumulate with age, since once a cell was lost through apoptosis, its double-strand damage would be lost with it. Thus, damaged DNA segments undermine the DNA replication machinery because these altered sequences of DNA cannot be utilized as true templates to produce copies of one's genetic material. [1]
In these cases, some DNA sequences do double duty, encoding one protein when read along one strand, and a second protein when read in the opposite direction along the other strand. In bacteria , this overlap may be involved in the regulation of gene transcription, [ 41 ] while in viruses, overlapping genes increase the amount of information ...