Difficulty planning, inhibiting unwanted responses, and coordinating thoughts might be seen in late adulthood due to the shrinkage of the cortex with age.

The given blank can be filled with prefrontal.

Explanation:

It is known that stress enhances the chances for the development of chronic illnesses like cardiovascular disease and hypertension. However, it has been found that stress also affects brain functioning. It has been demonstrated that chronic stress leads to long-term modifications in the brain, which results in mood disorders and anxiety.  

The chronic stress results in the loss of synaptic associations between the cells of the brain that could lead to a reduction in the mass of the brain or shrinkage in the prefrontal cortex, that is, the section of the brain just behind the forehead. The prefrontal cortex is mainly responsible for monitoring the behavior of an individual.  

It is the part of the brain, which is accountable for problem-solving, emotional processing and regulation, adaptation to challenges, and control of impulse. The shrinkage of the prefrontal cortex generally takes place during late adulthood, and one may find it tough to plan, preventing unwanted responses, and to coordinate thoughts.  

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.

a. to encourage apoptosis