Search results
Results from the WOW.Com Content Network
DNA exists in many possible conformations that include A-DNA, B-DNA, and Z-DNA forms, although only B-DNA and Z-DNA have been directly observed in functional organisms. [14] The conformation that DNA adopts depends on the hydration level, DNA sequence, the amount and direction of supercoiling, chemical modifications of the bases, the type and ...
[2] [3] The mRNA sequence is determined by the sequence of genomic DNA. [4] In this context, the standard genetic code is referred to as 'translation table 1' among other tables. [3] It can also be represented in a DNA codon table. The DNA codons in such tables occur on the sense DNA strand and are arranged in a 5 ′-to-3 ′ direction.
Given the two 10-nucleotide sequences, line them up and compare the differences between them. Calculate the percent difference by taking the number of differences between the DNA bases divided by the total number of nucleotides. In this case there are three differences in the 10 nucleotide sequence. Thus there is a 30% difference.
If amino acids were randomly assigned to triplet codons, there would be 1.5 × 10 84 possible genetic codes. [81]: 163 This number is found by calculating the number of ways that 21 items (20 amino acids plus one stop) can be placed in 64 bins, wherein each item is used at least once. [82]
DNA is a macromolecule made up of nucleotide units, which are linked by covalent bonds and hydrogen bonds, in a repeating structure. DNA synthesis occurs when these nucleotide units are joined to form DNA; this can occur artificially (in vitro) or naturally (in vivo). Nucleotide units are made up of a nitrogenous base (cytosine, guanine ...
A diagram of DNA base pairing, demonstrating the basis for Chargaff's rules. Chargaff's rules (given by Erwin Chargaff) state that in the DNA of any species and any organism, the amount of guanine should be equal to the amount of cytosine and the amount of adenine should be equal to the amount of thymine.
The linking number for circular DNA can only be changed by breaking of a covalent bond in one of the two strands. Always an integer, the linking number of a cccDNA is the sum of two components: twists (Tw) and writhes (Wr). [16] = + Twists are the number of times the two strands of DNA are twisted around each other.
For example 3 pairs of homologous chromosomes allow 8 possible combinations, all equally likely to move into the gamete during meiosis. This is the main reason for independent assortment. The equation to determine the number of possible combinations given the number of homologous pairs = 2 x (x = number of homologous pairs)