the ribs and rib cage are also flexible enough to expand and contract as the lungs fill and release with a person’s breath. In this article, learn more about the number of ribs humans have ...

The rib cage is part of the axial skeleton. The average human is born with the same number of ribs regardless of gender. The ribs articulate with the thoracic vertebra. For example, the first rib ...

Prime numbers are special numbers, greater than 1, that have exactly two factors, themselves and 1. 19 is a prime number. It can only be divided by 1 and 19. 9 is not a prime number. It can be ...