In order to study the formation of cancer cells, you should study the life cycle of normal cells as cancer cells are abnormal cells.
Actually, Normal cells grow, divides and died after an interval of time. And when this process is break down, cancer cells begin to form. They are usually old cells which don't die after their life cycle.
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Answer:
An Enhancer
Explanation:
Enhancers are the regulatory sequences and are generally located 80-160 base pairs upstream of the transcription start site. Enhancers have bidirectional elements that are involved in the initiation of transcription. Enhancers serve as the binding sites for activators to increase the concentration of activators in the vicinity of the promoter and thereby increase the rate of transcription of the gene.
According to the given information, the loss of a regulatory sequence led to a reduced level of transcription of the gene. This means that the regulatory sequence was involved in the upregulation of transcription. The presence of the sequence far away from the promoter makes it an enhancer.
Relative Humidity is considered as the most important factor in regulating the closing and opening of stomata. Since it indirectly controls transpiration and stomata's main function is transpiration.
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