Nervous System
Digestive System
Skeletal System
Muscular System
Reproductive System
100

The main organ that runs the nervous system.

What is the brain?

100

This is the longest organ in the digestive system.

What is the small intestine?

100

This is the longest bone in the human body.

What is the femur?

100

This muscle in the upper arm is responsible for flexing – bending the elbow to bring the wrist closer to the shoulder.

What are the biceps? 

100

This is the female reproductive organ which releases eggs.

What are the ovaries? 

200

The main units of the nervous system.

What is the neuron?

200

This digestive organ is responsible for filtering poisons out of the blood.

What is the liver?

200

The flat bone in the middle of the chest.

What is the sternum?

200

These are the main components/building blocks of muscles.

What is protein? 

200

The process in which eggs are released from the ovaries.

What is ovulation? 

300

This is how neurons communicate with each other.

What is electrical and chemical communication/signalling?

300

This is the main organ that stores bile (also known as gall) after it is made in the liver, before being released into the intestine.

What is the gallbladder?

300

The smallest bones of the human body.

What are the ear bones (malleus, stapes, incus)?

300

This wide, flat muscle controls our breathing.

What is the diaphragm? 

300

This hormone is responsible for male sexual traits and characteristics. 

What is testosterone? 

400

This is the gap between two neurons where communication occurs.

What is the synapse/synaptic cleft?

400

This is the name of the rhythmic, wave-like squeezing motions that move food through the digestive system.

What is peristalsis?

400

This is the main component that makes up bones.

What is calcium?

400

These tissues connect muscles to bones. 

What are tendons?

400

The number of chromosomes in a human sperm or egg cell. 

23 chromosomes. 

500

The material that wraps around a neuron to speed up signals.

What is a myelin sheath?

500

This is the acidic substance in the stomach that helps break down food.

What is hydrochloric acid?

500

This condition is due to a gradual loss of bone density and strength.

What is osteoporosis?

500

This is the type of muscle tissue that makes up your heart. 

What is cardiac tissue? 

500

The part of the female reproductive system that a fertilized egg attaches to and develops a fetus.

What is the uterus?