Muscles and Bones
Organs and Systems
Skin, Hair, and Nails
Brain and Senses
Weird but True Anatomy
100

This muscle, located in your backside, is the strongest muscle of the body  

What is the gluteus maximus?

100

This organ pumps about 100,000 times per day

What is the heart?

100

This organ is the largest in the body by surface area.

What is the skin?

100

This organ uses about 20 percent of the body’s oxygen.

What is the brain?

100

These body parts never stop growing.

What are the ears?

200

The smallest bone in the body is located in this organ

What is the ear? (The stapes)

200

This organ is the largest internal organ by mass.

What is the liver?

200

These glands help regulate temperature by releasing sweat.

What are sweat glands?

200

This sense can detect over 1 trillion odors.

What is smell?

200

The body contains enough of this metal to make a 3-inch nail

What is iron?

300

This bone in the thigh is the longest and strongest.

What is the femur?

300

This digestive organ is about 6 to 7 meters long.

What is the small intestine?

300

Humans shed about this many kilograms of skin in a lifetime. (For reference, 1 kilogram is about the weight of a liter of water or a small pineapple.)

What is 35 to 40 kilograms?

300

These eye cells detect light in low-light conditions.

What are rods?

300

The body can produce enough heat in 30 minutes to do this.

What is boil half a gallon of water?

400

Adults typically have this many total bones.

What is 206?

400

These organs filter about 150–180 liters of blood per day.

What are the kidneys?

400

Hair and nails are both made of this protein.

What is keratin?

400

This brain structure helps with balance and coordination.

What is the cerebellum?

400

This muscle is considered the strongest in the body relative to its size.

What is the tongue?

500

These cells build new bone

What are osteoblasts?

500

This body system produces hormones.

What is the endocrine system?

500

Goosebumps occur due to these small muscles.

What are arrector pili muscles?

500

These receptors detect pain

What are nociceptors?

500

This fluid makes up about 55 percent of total blood volume.

What is plasma?