<span>Every day, somewhere in our planet, a unique species of organism becomes extinct as the las member of that species dies. Some examples of this are the Caribbean Monk Seal, Tasmanian Tiger, Quagga, Passenger Pigeon, and the Baiji River Dolphin.
The answer is: <span>Its species.
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I hope it helps, Regards.</span>
<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.
<span>Carbon is the building blocks of all living molecules. With the ability to form carbon-carbon bonds, many different compounds formed into different structures can be used for different purposes such as macromolecules. </span>
The speed of a sound wave depends upon the medium through which it travels. In general, sound travels faster through solids than through liquids or gases. Also, the denser the medium, the slower sound will travel through it. The same sound will travel at a different speed on a cold day than it would on a warm day.
