sex at 11 to 15 years

11 to 15 years: Sex organs mature {sex development, 11 to 15 years}. Puberty averages two and a half years later in males than in females.

boys

Boys typically start at age 13, peak at age 14, and decline at age 15.5. Boys can start as early as 9.5 years or as late as 13.5 years.

girls

Girls typically start at age 11, peak at age 12, and decline at age 13. Girls can start as early as 7.5 or as late as 11.5 years. Breast buds appear at age 11, as areola diameter increases and small mound appears. One or two years before menarche, breast enlarges, nipples project, uterus grows, and pubic hair appears. At age 13, with range from 11 to 15, menarche starts and pigmented pubic hair grows. Climate does not affect menarche time. Menarche time has not decreased much over history. Malnutrition can delay menarche. Fertility is one to three years after puberty.

attitudes

Adolescent sexual attitudes are aggressive, exciting, shameful, dangerous, pleasant, and sharing.

cause

Gonadotropin-releasing-hormone (GnRH) release from hypothalamus triggers puberty, causing pituitary to secrete hormones that affect testes or ovaries. Kiss-1-gene enzyme {kisspeptin} activates GPR54, which also affects puberty.

Whole Section in One File

4-Zoology-Development-Stages-Adolescent 11-15 Years

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Date Modified: 2022.0224