Search results
Results from the WOW.Com Content Network
A segment of DNA. Genes are like sentences made of the "letters" of the nucleotide alphabet, between them genes direct the physical development and behavior of an organism. Genes are like a recipe or instruction book, providing information that an organism needs so it can build or do something - like making an eye or a leg, or repairing a wound.
DNA can be twisted like a rope in a process called DNA supercoiling. With DNA in its "relaxed" state, a strand usually circles the axis of the double helix once every 10.4 base pairs, but if the DNA is twisted the strands become more tightly or more loosely wound. [43]
Human genomes include both protein-coding DNA sequences and various types of DNA that does not encode proteins. The latter is a diverse category that includes DNA coding for non-translated RNA, such as that for ribosomal RNA , transfer RNA , ribozymes , small nuclear RNAs , and several types of regulatory RNAs .
Each strand of DNA is a chain of nucleotides, matching each other in the center to form what look like rungs on a twisted ladder. Although genes were known to exist on chromosomes, chromosomes are composed of both protein and DNA, and scientists did not know which of the two is responsible for inheritance.
Deoxyribonucleic acid (DNA) is a nucleic acid containing the genetic instructions used in the development and functioning of all known living organisms. The chemical DNA was discovered in 1869, but its role in genetic inheritance was not demonstrated until 1943. The DNA segments that carry this genetic information are called genes.
Digital karyotyping is a technique used to quantify the DNA copy number on a genomic scale. Short sequences of DNA from specific loci all over the genome are isolated and enumerated. [65] This method is also known as virtual karyotyping. Using this technique, it is possible to detect small alterations in the human genome, that cannot be ...
"When we look to the world of DNA, it is a wonderful tool," he said. "It's a powerful tool." Using DNA for identification, though, only works when there is something to compare it to.
Triple-stranded DNA (also known as H-DNA or Triplex-DNA) is a DNA structure in which three oligonucleotides wind around each other and form a triple helix. In triple-stranded DNA, the third strand binds to a B-form DNA (via Watson–Crick base-pairing ) double helix by forming Hoogsteen base pairs or reversed Hoogsteen hydrogen bonds.