A replication bubble forms as the DNA unwinds.
Option C
<u>Explanation</u>:
Replication bubble is the space where the strands of double helical DNA structure are separated with the help of DNA helicase. The strands of the double helical DNA are still in the helix form on the both end of the unwinded DNA stand which gives this region an appearance of a bubble.
DNA unwinding is the first step in replication or transcription of the DNA molecule. DNA helicase separates the two types of "DNA" that are connected by hydrogen bonds with the help of ATP hydrolysis.
Living things in the environment such as plants, animals, and bacteria are biotic factors. Biotic factors also include once-living parts such as dead leaves on the forest floor. Abiotic factors are nonliving aspects of the environment such as sunlight, temperature and water. One important abiotic factor is soil.
Microtubule – serves as a framework of the cell –cytoskeleton.<span>
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Nucleus – the control center of each cell. It regulates, monitors and organizes the whole cell<span>
Since the pictures isn't given I can assume that it can be the microtubule, the microtubule is responsible for maintaing the shape and structure of the overall cell. It maintains homeostasis by permanently aiding the framework of the overall cell.
If it is the nucleus, the control center of a cell. It does a lot of functions in the cell, it helps maintain homeostasis by sending commands that the organelles do, supply energy, excrete or digest waste, regulate the movement of objects and cellular respiration, even cell division. It sustains the cell to be functional and proactive at the same time reactive to situations that is likely to occur.
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The function of the respiratory system is to exchange two gases: oxygen and carbon dioxide.
Hope this helps :)
