Genetics: transcription translation help

In summary, this person created 7 different tRNAs to use with 6 different codons that each encoded one of the 23 possible amino acids. 20 different tRNAs are present in a typical cell, but there are some exceptions. The protein created has 7 amino acids, including the start codon.
  • #1
dagg3r
67
0
OK i just want some clarification on what i am doing is right if it is wrong please help me

first i have a template strand for a part of a DNA
this is
TAC CGA TGA CCA TCA GCC TGC

now this strand is decoded via the process of transcription into mRNA where it moves to the cytoplasm.

the mRNA formed is
AUG GCU ACU GGU AGU CGG ACG
now with this the mRNA attaches to ribosomes and each amino acid is brought to the mRNA on ribosomes by tRNA. these tRNA molecules have 3 bases that make up an anticodon.
this will form
UAC CGA UGA CCA UCG GCC UGC.

so far is my process right of transcription / translation.

now the questions

1. how many trna molecules did you make?
would this be 7 since there are 7 anticodons?
2. how many different trna molecules did you make?
*** not sure about this ***i would assume 7 since each trna anticodon are not the same order or is it each trna anticodon gives a different amino acid
3.how many different tRNA molecules would you expect to find in a cell
*** also had problem*** would this be 64 as 4^3 gives the different instructions i would find in a cell or would it be 20 as there are only 20 different amino acids that can be formed.
4.how many amino acids are there in the protein chain you made? how does this number relate to the number of triplets in the DNA molecule you started with? How does the number of amino acids relate to the number of codons in your mRNA molecule?
** please check***would there be 7 amino acids since this is the number of triplets, codons and anti-codons. the number of amino acids that are in the protein chain i made will relate to as the number of triplets, codons and anticodons is the number of amino acids that will be produced.

can someone please give me the best answer for this general question
1. what is meant when we say the 2 strands in a DNA molecule is anti-parallel.
 
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  • #2
dagg3r said:
1. how many trna molecules did you make?
would this be 7 since there are 7 anticodons?
2. how many different trna molecules did you make?
*** not sure about this ***i would assume 7 since each trna anticodon are not the same order or is it each trna anticodon gives a different amino acid

You should translate the mRNA. You will find that the question as a tricky part.

dagg3r said:
3.how many different tRNA molecules would you expect to find in a cell
*** also had problem*** would this be 64 as 4^3 gives the different instructions i would find in a cell or would it be 20 as there are only 20 different amino acids that can be formed.

32 different kinds of tRNA in a typical eukaryotic cell. Thus most amino acids have more than one tRNA responsible for them. The anticodon on the tRNA may change and also there codon bias in cells. Therefore some codons are used more often than other (http://www.iscb.org/ismb2004/posters/danny-kATactcom.co.il_271.html [Broken]). The third (wobble) position in the codon also allow for some limited codon (http://www.web-books.com/MoBio/Free/Ch5C4.htm)


dagg3r said:
4.how many amino acids are there in the protein chain you made? how does this number relate to the number of triplets in the DNA molecule you started with? How does the number of amino acids relate to the number of codons in your mRNA molecule?
** please check***would there be 7 amino acids since this is the number of triplets, codons and anti-codons. the number of amino acids that are in the protein chain i made will relate to as the number of triplets, codons and anticodons is the number of amino acids that will be produced.

Again translate the mRNA.

dagg3r said:
1. what is meant when we say the 2 strands in a DNA molecule is anti-parallel.

One strand goes 5'-3' whereas the other goes 3'-5'. It like two arrow that are parrallel but point in different direction
 
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  • #3
Translation

1) 7 tRNAs are needed. The first codon (AUG) is the start of the open reading frame, but encodes the amino acid Met.

2) 6 *different* tRNAs are needed because the codons ACU and ACG both encode the amino acid Thr. Each amino acid has its own tRNA synthesase, and subsequently its own tRNA, but since different codons can encode the same amino acid, different codons can utilize the same tRNA.

3) 20 different tRNAs are found in a typical cell. However, there are some exceptions to this rule, as in some bacteria that lack a tRNA for glutamine. In that case the tRNA for glutamate is used and glutamate is converted to glutamine via an amination reaction.

4) 7 amino acids are encoded for this protein, one amino acid per codon, including the start codon (AUG). It should also be noted that the sequence of codons for this problem does not include a stop sequence (UAG, UGA, or UAA).
 
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1. What is the difference between transcription and translation in genetics?

Transcription is the process of copying genetic information from DNA to RNA, while translation is the process of using that genetic information to create proteins. Transcription occurs in the nucleus of a cell, while translation occurs in the cytoplasm.

2. How does the genetic code determine the sequence of amino acids in a protein?

The genetic code is a set of rules that determines how the sequence of nucleotides in DNA corresponds to the sequence of amino acids in a protein. Each set of three nucleotides, called a codon, codes for a specific amino acid. This is how the genetic code directs the synthesis of proteins during translation.

3. What is the role of RNA polymerase in transcription?

RNA polymerase is an enzyme that helps to transcribe DNA into RNA. It binds to a specific region on DNA called the promoter and begins to unwind the double helix. It then reads the template strand of DNA and assembles a complementary strand of RNA, using base pairing rules. This results in a single-stranded RNA molecule that is a copy of the DNA sequence.

4. How does the genetic code account for the diversity of proteins in living organisms?

The genetic code is degenerate, meaning that some amino acids can be coded for by more than one codon. This allows for redundancy and flexibility in the code, which allows for the production of a variety of proteins with different sequences and functions. Additionally, post-translational modifications can further increase the diversity of proteins in an organism.

5. What can cause errors in transcription and translation, and how do they impact protein synthesis?

Errors in transcription and translation can be caused by mutations in the DNA sequence, which can result in changes in the genetic code. These changes can lead to the production of proteins with different amino acid sequences, which may affect their structure and function. Errors can also occur due to environmental factors, such as exposure to radiation or toxins, which can damage the DNA and affect the transcription and translation processes.

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