The embryo has become a fetus. His vital organs – such as kidneys, intestines, brain, and liver – are starting to function. Tiny fingernails and toenails are starting to form. 11 weeks: Your baby is almost fully formed. Her bones are beginning to harden, and her genitalia are developing externally. read more
Third trimester: Baby's brain grows. The third trimester is brimming with rapid development of neurons and wiring. Baby's brain roughly triples in weight during the last 13 weeks of gestation, growing from about 3.5 ounces at the end the second trimester to almost 10.6 ounces at term. read more
The brain is fully developed A. in the fetus. B. at birth. C. at the onset of adulthood. D. in the newborn. read more