ECONOMICS (CBSE/UGC NET)

Detailed explanation-1: -The brain reaches 90% of its adult size by the time a person is six or seven years of age. Thus, the brain does not grow in size much during adolescence. However, the creases in the brain continue to become more complex until the late teens.

Detailed explanation-2: -Although the brain stops growing in size by early adolescence, the teen years are all about fine-tuning how the brain works. The brain finishes developing and maturing in the mid-to-late 20s. The part of the brain behind the forehead, called the prefrontal cortex, is one of the last parts to mature.

Detailed explanation-3: -At birth, the average baby’s brain is about a quarter of the size of the average adult brain. Incredibly, it doubles in size in the first year and keeps growing to about 80% of adult size by age 3 and 90% – nearly full grown – by age 5.

Detailed explanation-4: -Although the brain reaches its full adult weight by the age of 21, it continues to develop for several years. In fact, a study done by the National Institutes of Health found that the region of brain that inhibits risky behavior does not fully form until age 25. This is the final stage of brain development.

Detailed explanation-5: -Neurulation. About 2 weeks after conception, the developing embryo has organized itself into a three-layered, spherical structure. Proliferation. Cell migration. Differentiation. Synaptogenesis. Synapse pruning. Myelination. Summary.