Instructions
- Read the Story: Read the introductory paragraph titled "The Body's Filter System" to understand how the renal system works.
- Word Bank Mastery: Use the words in the Word Bank to complete the System Map table below.
- Trace the Path: In the "Path of the Drop" section, number the steps in the correct order to show how waste moves through your body.
- Hydration Station: Analyze the hydration chart and answer the questions about keeping your kidneys healthy.
- Expert Challenge: Complete the bonus question at the end if you want to test your advanced knowledge!
The Body's Filter System
Imagine your body is like a busy city. As the city runs, it creates trash that needs to be hauled away. Your blood is like the delivery trucks moving through the city. The Renal System (also called the Urinary System) is the city's waste treatment plant. It cleans your blood, keeps the right amount of water in your body, and gets rid of liquid waste called urine.
Part 1: The System Map
Word Bank: Kidneys, Ureters, Bladder, Urethra, Renal Arteries
| Part Name | Where is it? | What is its job? |
|---|---|---|
| Kidneys | Two bean-shaped organs in your lower back | Filters waste and extra water out of the blood to make urine |
| These two thin tubes connect the kidneys to the bladder | ||
| A hollow, muscular sac located in the lower abdomen | ||
| The final tube that leads out of the body | ||
| The "highways" that bring blood into the kidneys to be cleaned | ||
Part 2: Path of the Drop
Below are the steps a drop of waste takes from the time it is in the blood until it leaves your body. Number them from 1 to 4 to put them in the correct order.
- [ ] The bladder fills up and sends a signal to your brain that it is time to go to the bathroom.
- [ ] The kidneys filter the blood and create a drop of urine.
- [ ] Urine travels through the urethra to exit the body.
- [ ] The urine travels down the long, skinny ureters.
Part 3: The Hydration Station
Your renal system needs water to work properly! Look at the "Hydration Check" descriptions below and answer the questions.
- Pale Yellow/Clear: You are well-hydrated. Your kidneys have plenty of water to help flush out waste.
- Bright Yellow: You are doing okay, but you should probably drink a glass of water soon.
- Dark Honey/Amber: You are dehydrated! Your kidneys are working extra hard because there isn't enough water to move the waste easily.
Questions:
-
If a marathon runner notices their urine is dark amber, what is their renal system trying to tell them?
-
Why do you think the kidneys need water to do their job of "filtering"? (Hint: Think about trying to wash dishes without any water!)
Part 4: Interactive Activity - The Kidney Model
In the space below, draw a simple diagram of the renal system. Be sure to include two kidneys, two ureters, one bladder, and one urethra. Label each part using the words from your Word Bank.
(Space for drawing)
Part 5: Expert Challenge
Your kidneys filter about 150 quarts of blood every single day, but you only pee about 1 or 2 quarts. What do you think happens to the rest of the liquid the kidneys "clean"?
Answer Key
Part 1: The System Map
- Ureters: Two thin tubes; Carries urine from kidneys to bladder.
- Bladder: Hollow sac; Stores urine until you are ready to pee.
- Urethra: Final tube; Allows urine to exit the body.
- Renal Arteries: Highways into kidneys; Delivers blood to be filtered.
Part 2: Path of the Drop
- The kidneys filter the blood...
- The urine travels down the ureters...
- The bladder fills up...
- Urine travels through the urethra...
Part 3: Hydration Station
- They are dehydrated and need to drink water immediately.
- Water acts as the "carrier" or the "rinse" to move waste particles out of the blood and through the tubes.
Part 5: Expert Challenge Most of the water and nutrients are reabsorbed back into the bloodstream to be used by the body again!