What is the main function of the circulatory system?
It carries blood to and from body cells
100
This is the control center of your nervous system.
Brain
100
The main organ of the respiratory system is the _____.
Lungs
200
What kind of muscle squeezes and relaxes without ever stopping?
Cardiac Muscle
200
After leaving the stomach, food enters the _______ ________.
Small Intestine
200
The heart is divided into four segments called ________.
chambers
200
What is the main function of the nervous system?
To send and receive messages to and from the body
200
Red blood cells deliver ______ to the body.
oxygen
300
What kind of muscles make up the wall of the stomach?
Smooth muscle
300
The stomach is made up of this kind of muscle.
Smooth Muscle
300
Tiny branch-like blood vessels that surround air-sacs in the lungs are called ______.
capillaries
300
A nerve cell is called a ________.
Neuron
300
The respiratory system works very closely with this organ.
Heart
400
What kind of muscle is moved voluntarily?
Skeletal Muscles
400
Nutrients are absorbed through the walls of this tube-like structure and into the bloodstream.
Small Intestine
400
What kind of blood vessel returns blood to the heart?
Veins
400
These groups of neurons pass along messages or signals between the body and the brain, much like a telephone wire.
Nerves
400
Why do you breath faster when exercising?
Your muscles are working hard and need more oxygen than when you are resting. They are also producing more carbon dioxide that needs to be removed from the body.
500
What is the name of the location where bones meet?
Joints
500
After you swallow, food travels down this tube that connects your mouth to your stomach.
Esophagus
500
What type of blood vessel carries blood away from the heart towards the body?
arteries
500
This tube of nerves runs through your spine and sends information between your body to your brain.
Spinal Cord
500
The waste product of cells is ______ _______. Your blood picks up this waste and delivers it back to the lungs to be breathed out.