When we look at old photos of our grandparents, we often notice how much their facial features have changed over the years, not only do they gain new wrinkles, but their noses and ears seem to become visibly larger over time.
The size of the ears and nose increases throughout life, but this is not because their tissues actually grow, as happens in childhood, for example.
“The ears and nose are fully developed by your 20s,” said Dr. Alan Matarasso, professor of clinical surgery at Zucker School of Medicine in New York. “After adolescence, most changes in their shape and size can be attributed to the aging process.”
The basic structures of both ears and nose are made of cartilage, a strong, elastic connective tissue that also serves to protect bones and joints.
Cartilage is composed of cells called chondrocytes, which are stabilized by a network of structural proteins called collagen and elastin. As we age, our bodies become less efficient at producing new collagen and elastin fibers, causing the entire cartilage structure to weaken and loosen, Matarasso said, Furthermore, age affects the structure of the tissue surrounding the cartilage. For example, facial tissues that were once tight begin to sag with age, and this, combined with the effects of gravity, leads to sagging earlobes and a drooping tip of the nose. This can contribute to increased nose and ear size, Matarasso said.
In addition, the skin on the nose can become heavier due to increased activity of the sebaceous glands.
However, Matarasso said the amount of change in nose and ear size over the years depends on a number of genetic and environmental factors.
Facial features in general are a highly hereditary trait. Nose shape, in particular, appears to be linked to a person's genetic makeup, according to a 2018 review published in the journal Frontiers in Genetics.
Regarding environmental factors, there is evidence to suggest that exposure to pollution and sun can accelerate aging processes in cartilage, Matarasso said.
Source News: Live Science Publication date: 27-12-2023 - https://r.rtarabic.com/wok0
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