Human Growth and Development

Here are some changes that puberty can bring in females and males. ●​ Males experience a series of changes during puberty, including the growth of testicles and penis, the development of pubic hair, and the ability to ejaculate. Voice changes occur as it deepens, facial hair begins to grow, and growth spurts are common. ●​ Females undergo different but equally significant changes, such as the development of breasts, the appearance of pubic hair, and the onset of their first menstrual period. Additionally, hips widen, and growth spurts occur during this period. Physical Development in Adulthood Early adulthood (ages 20 to 40) is considered the "prime of life," with peak physical performance that can be maintained through regular activity. Senescence , the start of physical decline begins around age 30. Strength and efficiency may decrease, and while height no longer increases, muscle mass and fat storage often do. Hormonal changes also occur, with a reduction in growth-related hormones.

During this period, major health problems are rare, with physicians mainly treating sports injuries and caring for pregnant women. While minor issues like colds and flu can occur, death is more likely to result from accidents than illness.

Many people also start families during this time, but around 15% of couples face infertility . Thankfully, medical interventions like in-vitro fertilization and artificial insemination can help. In middle adulthood , typically after age 40, visible signs of aging begin to appear. These may include: ●​ Development of gray hair

●​ Developing thin hair ●​ Discovering wrinkles ●​ Changes in bone density ●​ Changes in body shape

As people age, bone density decreases, and intervertebral discs lose elasticity, which can make them feel as though they are shrinking. Many also become overweight with age, affecting both men and women. Let's examine the decline in various body systems as we age.

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