Cell division and differentiation first begins during the germinal stage of prenatal development.
<u>Explanation:</u>
The development of the zygote into a full developed fetus occurs in three most prominent stages they are the germinal stage that occurs from the conception to the second week.
The embryonic stage that is from second week to the eighth week and the fetal stage that is from the eighth week till the birth of the baby. Each stage has its characteristic development that has to be completed.
The correct answer of the given question above is option A. The line of defense that his immune system is exhibiting in this situation is the first line of defense. The first line of defense includes the physical or external line of defense of the body that are responsible for inhibiting of the entry of foreign microorganisms. Such include the skin, tears, cilia, mucus, urine flow and even stomach acid.
Answer:
Although most adults won't grow taller after age 18 to 20, there are exceptions to this rule. First, the closure of the growth plates may be delayed in some individuals. If the growth plates remain open past age 18 to 20, which is uncommon, height could continue to increase.
There are 4 atoms in ammonia.