Answer: Option D) Norepinephrine
Explanation:
Norepinephrine, also known as noradrenaline acts as both a hormone and neurotransmitter.
Its effects is similar to epinephrine, in that during stress conditions epinephrine stimulates the heart to beat and pump blood faster, while norepinephrine helps to maintain blood pressure, causing the narrowing of the blood vessels, known as vasoconstriction.
The cell cycle is a four-stage process in which the cell increases in size (gap 1, or G1, stage), copies its DNA (synthesis, or S, stage), prepares to divide (gap 2, or G2, stage), and divides (mitosis, or M, stage). The stages G1, S, and G2 make up interphase, which accounts for the span between cell divisions.
Tumor-suppresor genes inhibit cell division in the cell-cycle to repair DNA that is damaged or abnormal chromosomes to stop the mutation of such genes which causes pathology in the body.
