The Brain
What is the brain’s size compared to?
A coconut
What do nerve cells also get called?
Neurons
How many kidneys do you have?
Two
What do your lungs excrete?
Waste gases (like carbon dioxide)
How fast do signals travel compared to an airplane?
About the same speed as an airliner (400 km/h)
What does the surface of the brain look like?
Wrinkled like a walnut
What do axons act like inside your body?
Wires that carry messages
What is the size of a kidney compared to?
About the size of your fist
What do your kidneys excrete?
Waste water (urine)
What special “booster” did the biggest dinosaurs have?
A booster at the base of their tails to speed up signals
What does the brain do with unimportant signals?
It ignores them
How fast do signals travel to the brain?
400 km/h (111 m/s)
What bag stores urine before it leaves the body?
The bladder
What gives urine its pale yellow color?
Waste products
Can you live with just one kidney?
Yes, the other kidney grows to do the work of two
Name two organs (besides the brain) that send signals to the brain.
eyes, ears, nose, tongue, skin, internal organs
What is the longest type of cell in your body?
Nerve cells (neurons)
What do kidneys hold onto if you are drying out?
Water
What would happen if you never excreted waste?
It would build up and harm your body
What machine can replace kidney function if they fail?
dialysis machine
Explain why your brain could be overloaded, and how it prevents this.
It receives signals from all senses and organs, but filters to focus only on important ones
How does the brain alert you to a problem? Give two examples.
It tells you when you are hungry, tired, or need the lavatory
What is the main function of the kidneys in blood filtration?
They filter blood, removing waste products while keeping salts the body needs
Describe the path of waste water from the kidneys out of the body.
Kidneys → bladder → leaves body when you go to the lavatory
Why can people donate a kidney?
Because humans can survive with one kidney, so they can give one to someone in need