Q 01/05

How many bones does an adult human normally have?

A) About 206

B) About 106

C) About 306

D) About 500

Answer · why

A) About 206

Babies start with around 270; many fuse together as we grow, especially in the skull and spine.

Q 02/05

Which is the longest in the human skeleton?

A) The shin (tibia)

B) The upper arm (humerus)

C) The forearm (ulna)

D) The thigh (femur)

Answer · why

D) The thigh (femur)

It is also the largest and thickest, and the only bone in the upper leg.

Q 03/05

The smallest bone in the body is shaped like a stirrup. Where is it?

A) In the little toe

B) In the nose

C) In the ear

D) In the wrist

Answer · why

C) In the ear

It is called the stapes and passes sound vibrations to the inner ear. It is one of three tiny bones there.

Q 04/05

Which is the only bone in the body not connected to any other bone?

A) The kneecap, in the knee

B) The hyoid, in the throat

C) The tailbone, at the base of the spine

D) The collarbone, at the shoulder

Answer · why

B) The hyoid, in the throat

It sits above the voice box, held by muscles, and helps anchor the tongue for swallowing and speech.

Q 05/05

Roughly how big is the human heart usually said to be?

A) The size of a grapefruit

B) The size of a closed fist

C) The size of a golf ball

D) The size of a football

Answer · why

B) The size of a closed fist

It sits between the lungs, slightly to the left, with the atria on top and the ventricles below.