AP PSYCHOLOGY

Detailed explanation-1: -A new born’s head is very large in proportion to the body, and the cranium is enormous relative to his or her face. the new born’s is about ¼. Normal head circumference for a full-term infant is 33–36 cm at birth.

Detailed explanation-2: -Generally, a newborn’s head is about half the baby’s body length in cm plus 10 cm. So a baby that is 18 inches long would be 45.7 centimeters (18 x 2.54). His or her head would be about 32.9 cm or a little under 13 inches.

Detailed explanation-3: -Your baby’s brain grows quickly during their first year of life. To accommodate the growing brain, your baby’s head has to grow, too. During their first year of life, a baby’s head grows 12 centimeters.

Detailed explanation-4: -At birth the head is one-fourth the total body length, whereas in the adult it is one-seventh (Fig. 5). Also the trunk is long with the upper limbs being longer than the lower limbs. From the second half of the first year to puberty the extremities grow more rapidly than the head.

Detailed explanation-5: -Having a larger head size can be harmless, if a larger head size is a family trait, or it can be a sign of a serious medical condition. Common medical conditions include an enlarged brain, brain bleed, fluid on the brain and genetic disorders. Treatments are specific to the cause.