<span> Because stem-cell therapies are relatively new and their side effects have yet to be completely discovered.
Long delays associated with the search for organ donors
Large payments to secure a bone marrow donor
Possibility that the organ may be rejected</span>
Answer:
The change in total population over a period is equal to the number of births, minus the number of deaths, plus or minus the net amount of migration in a population. The number of births can be projected as the number of females at each relevant age multiplied by the assumed fertility rate.
Pernicious anemia<span> is a decrease in red blood cells that occurs when the intestines cannot properly absorb vitamin B12.</span>