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Which of the following statements concerning ribosomes are true? Several ribosomes are often attached to and translating the same mRNA. Ribosomes join amino acids to form a polypeptide. Ribosomes have a binding site for mRNA and three binding sites for tRNA molecules. No protein synthesis within a cell would occur without ribosomes. All of the above statements are true.

User Warpech
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2 Answers

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Final answer:

All provided statements about ribosomes are true: they can be attached to the same mRNA as polysomes, they join amino acids to form polypeptides, have mRNA and tRNA binding sites, and are essential for protein synthesis.

Step-by-step explanation:

The statements concerning ribosomes provided in the question are all true. Several ribosomes are indeed often attached to and translating the same mRNA, which is a process that greatly increases the efficiency of protein synthesis. This arrangement is known as a polyribosome or polysome. Ribosomes join amino acids to form a polypeptide chain through a process known as elongation, where tRNA molecules bring the appropriate amino acids to the ribosome, which are then connected together by peptide bonds.

Ribosomes have a binding site for mRNA and three binding sites for tRNA molecules—designated the A (aminoacyl), P (peptidyl), and E (exit) sites—, which are crucial for the translation process. Without ribosomes, protein synthesis within a cell would not occur, as they are essential components of the cellular machinery responsible for producing proteins.

User Yassir Irfan
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4 votes

Answer:

1) Several ribosomes are often attached to and translating the same mRNA- True

2) Ribosomes join amino acids to form a polypeptide - True

3) Ribosomes have a binding site for mRNA and three binding sites for tRNA molecules- True

4) No protein synthesis within a cell would occur without ribosomes- True

Explanation:

1) When a messenger RNA is being translated, a number of ribosomes are invariably seen to be attached along the length of the mRNA thread. This complex of ribosomes and mRNA is called a polyribosome, or polysome.

2) Ribosomes have binding sites on them for tRNAs which bind to the ribosomal sites and help in the peptide bond formation between amino acids. So ribosome help in the process.

3) Ribosomes bind to the mRNA on the Start or initiation codon and have three binding sites namely P, A , E where the tRNA binds.

4) Ribosomes are the protein factories of the cell.

ALL ARE TRUE!! Hope it helps!!

User Lemondoge
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