Kristina S
bio help pleaseee
Answer
To summarize what I copied for you below, a wobble interaction is the interaction formed between the third base of a tRNA codon between that tRNA molecule and a ribosome. As you probably know, there are 20 standard amino acids. These 20 standard amino acids are encoded by 61 codons, each codon containing 3 bases. If you look closely at a list of codons that encode for a single amino acid, you may notice that one amino acid is encoded by many codons, usually with the first 2 bases the same, and the third codon variable. This third codon is known as a wobble, and the bond formed between this third base on the tRNA and the ribosome is not as stable, thus its importance is diminished.
A wobble base pair is a G-U and I-U / I-A / I-C pair fundamental in RNA secondary structure. Its thermodynamic stability is comparable to that of the Watson–Crick base pair. Wobble base pairs are critical for the proper translation of the genetic code. The genetic code makes up for disparities in the number of amino acids (20) for codons (64), by using modified base pairs in the first base of the anti-codon. One important modified base is hypoxanthine (more commonly referred to by its nucleoside form, inosine), which can pair with three bases: uracil, adenine, and cytosine.
Another critical base pair is the G-U base pair, which allows uracil to pair with two bases: guanine and adenine.
The fact that there are 61 amino-acid-coding codons and about 45 tRNA molecules presented a problem; in 1966 Francis Crick proposed the Wobble hypothesis to account for this. He postulated that the 5' base on the anti-codon, which binds to the 3' base on the mRNA, was not as spatially confined as the other two bases, and could thus have non-standard base pairing.[1] This would account for there being 61 codons compared to only about 45 tRNA.
As an example yeast tRNAPhe has the anticodon 5'-GmAA-3' and can recognize the codons 5'-UUC-3' and 5'-UUU-3'. It is, therefore, possible for non-Watson–Crick base pairing to occur at the third codon position; i.e. the 3' nucleotide of the mRNA codon and the 5' nucleotide of the tRNA anticodon.
To summarize what I copied for you below, a wobble interaction is the interaction formed between the third base of a tRNA codon between that tRNA molecule and a ribosome. As you probably know, there are 20 standard amino acids. These 20 standard amino acids are encoded by 61 codons, each codon containing 3 bases. If you look closely at a list of codons that encode for a single amino acid, you may notice that one amino acid is encoded by many codons, usually with the first 2 bases the same, and the third codon variable. This third codon is known as a wobble, and the bond formed between this third base on the tRNA and the ribosome is not as stable, thus its importance is diminished.
A wobble base pair is a G-U and I-U / I-A / I-C pair fundamental in RNA secondary structure. Its thermodynamic stability is comparable to that of the Watson–Crick base pair. Wobble base pairs are critical for the proper translation of the genetic code. The genetic code makes up for disparities in the number of amino acids (20) for codons (64), by using modified base pairs in the first base of the anti-codon. One important modified base is hypoxanthine (more commonly referred to by its nucleoside form, inosine), which can pair with three bases: uracil, adenine, and cytosine.
Another critical base pair is the G-U base pair, which allows uracil to pair with two bases: guanine and adenine.
The fact that there are 61 amino-acid-coding codons and about 45 tRNA molecules presented a problem; in 1966 Francis Crick proposed the Wobble hypothesis to account for this. He postulated that the 5' base on the anti-codon, which binds to the 3' base on the mRNA, was not as spatially confined as the other two bases, and could thus have non-standard base pairing.[1] This would account for there being 61 codons compared to only about 45 tRNA.
As an example yeast tRNAPhe has the anticodon 5'-GmAA-3' and can recognize the codons 5'-UUC-3' and 5'-UUU-3'. It is, therefore, possible for non-Watson–Crick base pairing to occur at the third codon position; i.e. the 3' nucleotide of the mRNA codon and the 5' nucleotide of the tRNA anticodon.
Does our sun wobble?
bwfrieds
If our sun was carefully watched from Andromeda for over 3000 Earth orbits, would the gravitational attraction between the sun and its orbiting planets cause it to move a bit? Assume that Andromeda is perfectly stable and does not wobble.
Answer
Yes.
Although not very much.
This technique is one of those used by us to detect planets in other solar systems. (Although these are a heck of a lot closer than the Adromeda Galaxy.) The offical name for this method is "astrometric detection."
The largest wobbles we can see occur when there is a relatively large planet very close to the star. Planets such as these are called "hot jupiters."
For someone else to detect a wobble from us they would need better instruments. Most of the wobble from the sun would come from Jupiter - its effect dwarfs that of all the other planets combined. But since Jupiter is, relatively speaking, far away from the Sun the extent of the wobbling is small.
Details on planets found thus far around other stars, using a variety of techniques, are included in these links. Note: the Extrasolar Planet Encyclopedia is an official resource for actual astronomers.
Yes.
Although not very much.
This technique is one of those used by us to detect planets in other solar systems. (Although these are a heck of a lot closer than the Adromeda Galaxy.) The offical name for this method is "astrometric detection."
The largest wobbles we can see occur when there is a relatively large planet very close to the star. Planets such as these are called "hot jupiters."
For someone else to detect a wobble from us they would need better instruments. Most of the wobble from the sun would come from Jupiter - its effect dwarfs that of all the other planets combined. But since Jupiter is, relatively speaking, far away from the Sun the extent of the wobbling is small.
Details on planets found thus far around other stars, using a variety of techniques, are included in these links. Note: the Extrasolar Planet Encyclopedia is an official resource for actual astronomers.
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