AP BIOLOGY

Detailed explanation-1: -The adult human skeleton is made up of 206 bones. These include the bones of the skull, spine (vertebrae), ribs, arms and legs.

Detailed explanation-2: -In humans 206 bones are found. So, option A of 306 bones is wrong.

Detailed explanation-3: -The axial skeleton, comprising the spine, chest and head, contains 80 bones. The appendicular skeleton, comprising the arms and legs, including the shoulder and pelvic girdles, contains 126 bones, bringing the total for the entire skeleton to 206 bones.

Detailed explanation-4: -There are typically around 270 bones in human infants, which fuse to become 206 to 213 bones in the human adult. The reason for the variability in the number of bones is because some humans may have a varying number of ribs, vertebrae, and digits.

Detailed explanation-5: -It’s time to look at all your bones-the adult human body has 206 of them!