Human Body

Reproduction and Human Development

What are some general effects of aging on the human body?

The aging process affects every organ system. Some changes begin as early as ages 30 to 40. The aging process becomes more rapid between ages 55 and 60.

  Effects of Aging
Organ System Effect of Aging
Integumentary Loss of elasticity in the skin tissue, producing wrinkles and sagging skin; oil glands and sweat glands decrease their activity, causing dry skin; hair thins
Skeletal Decline in the rate of bone deposition, causing weak and brittle bones; decrease in height
Muscular Muscles begin to weaken; muscle reflexes become slower
Nervous Brain size and weight decreases; fewer cortical neurons; rate of neurotransmitter production declines; short-term memory may be impaired; intellectual capabilities remain constant unless disturbed by a stroke; reaction times are slower
Sensory Eyesight is impaired with most people becoming far-sighted; hearing, smell, and taste are reduced
Endocrine Reduction in the production of circulating hormones; thyroid becomes smaller; production of insulin is reduced
Cardiovascular Pumping efficiency of the heart is reduced; blood pressure is usually higher; reduction in peripheral blood flow; arteries tend to become more narrow
Lymphatic Reduced sensitivity and responsiveness of the immune system; increased chances of infection and/or cancer
Respiratory Breathing capacity and lung capacity are reduced due to less elasticity of the lungs; air sacs in lungs are replaced by fibrous tissue
Digestive Decreased peristalsis and muscle tone; stomach produces less hydrochloric acid; intestines produce fewer digestive enzymes; intestinal walls are less able to absorb nutrients
Excretory Glomerular filtration rate is reduced; decreased peristalsis and muscle tone; weakened muscle tone often leads to incontinence
Reproductive Ovaries decrease in weight and begin to atrophy in women; reproductive capabilities cease with menopause in women; sperm count decreases in men


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