which of the following nucleic acids carries amino acids to organelles called ribosomes in which the amino acids are linked one by one to produce a po

ATI TEAS 7

ATI TEAS 7 Science

1. Which of the following nucleic acids carries amino acids to organelles called ribosomes, where the amino acids are linked one by one to produce a polypeptide?

A. DNA
B. mRNA
C. rRNA
D. tRNA

Correct answer: D

Rationale: tRNA is the correct answer as it carries amino acids to the ribosomes during protein synthesis. Transfer RNA (tRNA) plays a crucial role in protein synthesis by bringing specific amino acids to the ribosome according to the mRNA sequence. Once at the ribosome, the amino acids are linked together to form a polypeptide chain. This process is essential for the creation of proteins in the cell, highlighting the significance of tRNA in the translation process. Choice A, DNA, is incorrect as DNA does not directly participate in protein synthesis. Choice B, mRNA, is incorrect as mRNA carries the genetic information from DNA to the ribosome but does not directly carry amino acids. Choice C, rRNA, is incorrect as ribosomal RNA is a component of the ribosome structure and is involved in protein synthesis but does not carry amino acids like tRNA.

2. Which of the following is NOT a characteristic of mitosis?

A. The replication of DNA
B. The condensation of chromosomes
C. The separation of sister chromatids
D. The formation of haploid cells

Correct answer: D

Rationale: Rationale: A) The replication of DNA is a characteristic of mitosis. Before cell division occurs, the DNA is replicated to ensure that each daughter cell receives a complete set of genetic information. B) The condensation of chromosomes is a characteristic of mitosis. During mitosis, the chromosomes condense and become visible under a microscope as distinct structures. C) The separation of sister chromatids is a crucial step in mitosis. During anaphase, the sister chromatids are pulled apart and move to opposite poles of the cell to ensure that each daughter cell receives a complete set of chromosomes. D) The formation of haploid cells is NOT a characteristic of mitosis. Mitosis results in the formation of two identical diploid daughter cells, each containing the same number of chromosomes as the parent cell. Haploid cells are typically formed through the process of meiosis, not mitosis.

3. What is the importance of RNA splicing?

A. Removes introns from the mRNA molecule
B. Adds the poly-A tail to the mRNA molecule
C. Activates the mRNA molecule for translation
D. Modifies the structure of the protein

Correct answer: A

Rationale: RNA splicing is a crucial process in gene expression where non-coding regions called introns are removed from the pre-mRNA molecule, and the remaining coding regions called exons are joined together to form the mature mRNA molecule. This process ensures that only the protein-coding sequences are retained in the mRNA for translation, allowing for the production of functional proteins. Therefore, option A is the correct answer as it accurately describes the importance of RNA splicing in generating mature mRNA molecules for protein synthesis. B) Adding the poly-A tail to the mRNA molecule is a post-transcriptional modification that occurs after RNA splicing and is not directly related to the process of removing introns. C) Activating the mRNA molecule for translation is typically achieved through the addition of a 5' cap and the poly-A tail, rather than through RNA splicing. D) Modifying the structure of the protein is not directly related to the process of RNA splicing, which primarily focuses on mRNA maturation by removing non-coding introns.

4. Acids are generally characterized by a sour taste and the ability to:

A. Turn litmus paper red
B. Conduct electricity in solution
C. Neutralize bases
D. React explosively with metals

Correct answer: C

Rationale: Acids are known for their sour taste and their ability to neutralize bases, which is a defining characteristic of their acidic nature. When acids neutralize bases, salts and water are formed, highlighting the unique property of acids. The other options are incorrect: Option A, 'Turn litmus paper red,' is a test for acidity but not a defining characteristic of acids; Option B, 'Conduct electricity in solution,' pertains to the electrolytic properties of acids rather than their defining trait; Option D, 'React explosively with metals,' is not a general characteristic of acids. Therefore, the correct feature associated with acids is their capability to neutralize bases, making option C, 'Neutralize bases,' the correct answer.

5. Which of the following is NOT a function of the liver?

A. nutrient processing
B. blood filtration and detoxification
C. cholesterol and lipoprotein production
D. insulin production and blood sugar regulation

Correct answer: D

Rationale: The correct answer is D. The liver does not produce insulin; instead, insulin is produced by the pancreas. The liver plays a crucial role in regulating blood sugar levels by storing and releasing glucose but does not directly produce insulin. Choices A, B, and C are functions of the liver. Nutrient processing, blood filtration, detoxification, cholesterol, and lipoprotein production are essential roles performed by the liver to maintain overall metabolic balance and health.