Fill in the blanks.
The _______ period lasts from conception to implantation of the zygote in the lining of the uterus. During this time, the organism begins cell division and growth.
The first trimester is a critical stage in human development because nutrient deficiencies____________.
Throughout the prenatal period, the embryo/fetus depends entirely on its _______________ .
A very preterm infant who is born after about 26 weeks of pregnancy may _______________.