In the places of the greatest load on the bone in the compact substance, the bone plates intersect at a certain angle for maximum strength and the bone thickness in these places is greater. Lightness is provided by the presence of cavities in the tubular bones and air bones, so that the skeleton makes up 10-12% of the body weight of an adult, and its strength can be compared to cast iron.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.