Correct answer: Option D- DNA ligase
Explanation: In option A, thymine is a nucleotide, so it is present throughout the replication process, wherever it is required. It is added to the newly formed DNA. In option B, Helicase enzyme is active during initiation and elongation stage, as it facilitates the opening of the winded DNA strands. Option C is nucleotidase and it has no role in DNA replication. So, the correct answer is DNA ligase, which is option D.
The okazaki fragments formed during DNA replication are sealed at the end. And in this step, DNA ligase is used. It catalyzes the formation of phosphodiester bond between the nucleotides of okazaki fragments. So it is the last active molecule of the process.
<h2>Cell Cycle
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Explanation:
Eukaryotes grow and divide by cell cycle.
The main parts of a cell cycle are an ordered series of events – Gap 1 or G1 phase, Synthesis or S phase, Gap 2 or G2 phase, and the mitosis or M phases.
Interphase period (G1, S, G2 phases) - cell grows by size, duplicates its content, replicates its DNA, and finally prepares for mitotic cell division
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Mitosis and cytokinesis - formation of two identical daughter cells
Cell cycle is regulated by regulatory or restrictive checkpoints in the cell cycle which are activated with detection of a defective DNA.
Proliferation of undesired or cells with defective DNA like in case of tumor cells is controlled by the action of suppressing agents like p53 and cyclins.
The tumor suppressor gene protein p53 prohibits division of tumor cells. Cyclins regulate cell cycle by activation of the enzyme cyclin-dependent kinase.
Answer:
Make reclamation mandatory after limestone has been removed
Explanation:
The Answer is the Intertidal Zone
