Q 01/05

How many bones does a typical adult human skeleton have?

A) 206

B) 256

C) 306

D) 356

Answer · why

A) 206

Newborns start with around 270 separate bones, many of which fuse during childhood. Bone mass keeps growing until about age 25 to 30.

Q 02/05

Roughly how many bones is a human baby born with, before many of them fuse?

A) About 150

B) About 206

C) About 270

D) About 350

Answer · why

C) About 270

The skull alone has soft fontanelles that let it squeeze through the birth canal and then close. Fusion of the last growth plates finishes in the mid-...

Q 03/05

How many bones are in the axial skeleton (skull, spine and rib cage)?

A) 80

B) 100

C) 126

D) 140

Answer · why

A) 80

The appendicular skeleton of limbs and girdles holds the other 126. Together they make up about 14% of total body weight.

Q 04/05

Roughly what share of your total body weight is bone?

A) About 4%

B) About 14%

C) About 30%

D) About 45%

Answer · why

B) About 14%

Bone marrow, tucked inside those bones, adds another 5% or so on its own. Water and muscle make up most of the rest.

Q 05/05

Which bone is the largest and thickest in the human body?

A) Femur

B) Skull

C) Sternum

D) Pelvis

Answer · why

A) Femur

On average it accounts for 26.74% of a person's height, which is why forensic scientists can estimate stature from a single thigh bone. Its ball-shape...