Question

During development which of the following organs is formed first?
a) Heart
b) Brain
c) Neural tube
d) Skin

Answer 1

Hint:The zygote is formed from the fusion of the male and female gametes. The embryo develops and from the cells, the tissue is formed which leads to the formation of various organs and tissues of the body. The development of organs takes place in week five and is known as the embryonic period.

Complete Answer:-
After implantation, the blastocyst has been successfully implanted in the uterine wall. The notochord formed is present of the mesodermal origin and it then causes the ectoderm layer present above it to roll and then form the neural plate. The rolled ectoderm layer forms the neural tube of the embryo. The neural tube leads to the formation of the brain and spinal cord in the embryo body. This then leads to the formation of the blood vessels. The nerve cells and kidney cells also develop. This all happens in the first trimester. The first trimester is the riskiest for the development of the baby. Most miscarriages usually occur in these first three months. During the sixth and the seventh week, the digits of the embryo are formed and the eyes and ears also begin to develop. In the ninth week, the formation of nipples and hair follicles take place. The arms and elbows start to grow. The essential organs required by the embryo grow during this time. As the time passes, the growth of the organs and the external features of the baby becomes more prominent. By week 20, the baby is able to listen to sounds and is able to make bowel movements too.
Thus, the right option is C.

Note:- The body of the embryo develops fully by the end of the week 20 and is able to perform different small functions. The baby is able to float around the uterus and is able to hear sounds. After the pregnancy period is over, a fully formed baby emerges out.