All Free Biology MCQs with Answers
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19844 questions · page 727 of 1985
7261. Total number of genetic codes is:
- A. 43
- B. 60
- C. 64
- D. 68
Explanation: The total number of possible genetic codes is 64. This is because there are 4 different nucleotides (A, C, G, and U) that can be arranged into codons of 3 nucleotides each. With 4 options for each of the three positions in a codon, there are 4^3 = 64 possible combinations.
Correct answer: 647262. Which of these initiation code?
- A. AUU
- B. AUG
- C. UGA
- D. UCC
Explanation: The initiation codon, which also serves as the start codon for protein synthesis, is AUG. This codon codes for the amino acid methionine and signals the beginning of translation. In addition to encoding methionine, AUG also functions as the site where the ribosome begins the process of translation, ensuring that the correct reading frame is established for protein synthesis.
Correct answer: AUG7263. Which of the followings is not termination or non-sense code?
- A. UAA
- B. UAG
- C. UCC
- D. UGA
Explanation: The codon UCC, which codes for the amino acid serine, is not a termination or nonsense codon. Instead, it specifies an amino acid in the genetic code. Termination or nonsense codons signal the end of translation and do not code for any amino acids.
Correct answer: UCC7264. Which of the followings is mismatched for genetic code?
- A. Crick
- B. Watson
- C. Nirenberg
- D. Philip Leader
Explanation: Explanation for this question will be added soon!
Correct answer: Watson7265. The code of arginine is:
- A. CAU
- B. CCU
- C. CGU
- D. CAA
Explanation: The genetic code for arginine is represented by the codons CGU, CGC, CGA, CGG, AGA, and AGG. These codons all code for the amino acid arginine. So, CGU is just one of the codons that code for arginine, not the "code of arginine" itself.
Correct answer: CGU7266. The genetic code for alanine is:
- A. GUU
- B. GUA
- C. GUC
- D. GCU
Explanation: The genetic code for the amino acid alanine is represented by the codons GCU, GCC, GCA, and GCG. These four codons all code for the amino acid alanine.
Correct answer: GCU7267. Genetic code for phenylalanine is:
- A. CCC
- B. UUU
- C. AAA
- D. GGG
Explanation: The genetic code for the amino acid phenylalanine is represented by the codons UUU and UUC. These two codons both code for the amino acid phenylalanine.
Correct answer: UUU7268. Genetic code for glycine is:
- A. UUU
- B. GCU
- C. GCA
- D. GGC
Explanation: The genetic code for the amino acid glycine is represented by the codons GGU, GGC, GGA, and GGG. These four codons all code for the amino acid glycine.
Correct answer: GGC7269. The site of ribosome where peptide bond is formed is:
- A. A site
- B. P site
- C. E site
- D. None of the above
Explanation: Proteins called initiation factor position the tRNA on the ribosomal surface at the P site (peptidyl site) where peptide bonds will form. Nearby two other sites will form. A site (for aminoacyl site), where successive amino acid bearing tRNAs will bind and the E site (for exit site) where empty tRNAs will exit the ribosome
Correct answer: P site7270. Empty tRNA is present in:
- A. A site
- B. P site
- C. E site
- D. None of the above
Explanation: Explanation for this question will be added soon!
Correct answer: E site