s - orbitals have a spherical symmetry and the probability of finding an electron in an s orbital is equal for equal distance in x, y or z direction. i mean the probability of lets say an electron found at a distance 10 units from nuclues, its value will be same for x, y and z when u go 10 units distnace from nucleus in these directions. then the value at 5 units would be some value which also would be same for x,y and z.
Easier explanation is that if u place a ball, can u tell towards which axis it is oriented? no, its equally in all directions. So, non- directional.
However, if you have p- orbitals like dumb bells, a dumb bell can be oriented in three different directions, either x or y or z. see the pics.
Half-life is defined as the amount of time it takes a given quantity to decrease to half of its initial value. The equation to describe the decay is
Nt=N0(1/2)

where N0 is the initial quantity, Nt is the remaining quantity after time t, t1/2 is the half-time. So work out the equation, t1/2 = t (-ln2)/ln(Nt/N0) = 11.5*(-ln2)/ln(12.5/100) = 3.83 days
Answer:
Option (D)
Explanation:
Phosphorylation can be simply defined as the addition of a phosphate group to an organic and inorganic molecule. This process helps in regulating the processes that occur in the cells. It leads to the growth and development of cells and this process is efficiently carried out with the help of enzymes like kinase. It also plays an important role in transferring the signals within the cells, synthesis, and functioning of proteins within the cells, and storing as well as releasing of energy.
Thus, the correct answer is option (D).
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