The Urinary System Our Bodies are Amazing Our

The Urinary System

Our Bodies are Amazing! Our bodies are made up entirely of cells, the basic unit of life. There are over 50 trillion cells in our bodies. That’s over 50, 000, 000 and they all work together!

Cells are too small to see without a microscope. Different cells group together to form tissues. When tissues work together they form organs. Can you name any organs?

When organs work together they are called an organ system! Let’s recap! Each organ system has a different job to do within our bodies.

Our Organ Systems Muscular System Skeletal System Protection Breathing Urinary System Digestive System Integumentary System (skin) Respiratory System Support Nervous System Cardiovascular System Moving Digestion Pumping Thinking ? ? ?

What does the Urinary System do? “We are the Urinary System and we’re kind of a big deal. ” The Urinary System gets rid of waste and excess water in the form of urine. Since urine output is not constant, the urinary organs transport and store urine till it’s time for release.

Organs of the Urinary System: • 2 Kidneys 1 • 2 Ureters 1 2 2 1 • 1 Bladder • 1 Urethra 2

Each Urinary Organ has a Different Job • 2 Kidneys: filters waste from blood making urine • 2 Ureters: carries urine from kidneys to your bladder 1 2 • 1 Bladder: stores urine • 1 Urethra: carries urine from bladder to outside your body

#1 #2 The Kidneys The kidneys filter out wastes and excess water from our blood. Inside a kidney. Blood, waste and water enter the kidney here through the Renal Artery. Blood cleaned of waste and excess water leave the kidney here through the Renal Vein. All the wastes and excess water leave the kidney in the form of urine via the ureter.

Kidneys & Spaghetti When making spaghetti you boil the noodles in water first. Once the noodles are soft you get rid of the water, it is no longer needed. We do this with a strainer, which keeps what we need (noodles) and lets go of what we don’t (the water). Kidneys work the same way! They filter the nutrients we need to keep and let the wastes and extra water leave.

Kidneys and Water Our kidneys also regulate the amount of water we have in our bodies. Humans are made up of about 70% water! So it is important to drink enough water to replace the water that leaves the body as sweat, urine, tears, and spit. This is called water balance. When we have excess or too much water the kidney also filters it out as urine.

Let’s give your Kidneys a pat on the back! 1. Stand up. 2. Place your hands on your hips. 3. Slide them up until you feel your ribs. 4. Put your thumbs on your back. You are now touching your kidneys! Yay!

Kidneys The Ureters Once the kidneys filters out the wastes and excess water from our blood, the wastes leave as urine. Ureters Bladder The ureters are like a tube that carries the urine away from the kidneys. There is one ureter for each kidney and they take the urine to the bladder for storage.

Ureters & Water Hoses Ureters are like water hoses. Both are tubes that carry liquids from one place to place. Water hoses can carry water to a water balloon to be stored in. Ureters carry urine to the bladder for storage.

Bladder The bladder is a hollow organ, like an empty balloon. Also like a balloon, the bladder expands in size as it is filled. The bladder stores urine until we go to the bathroom.

Urethra The urethra is the last tube urine passes through to leave the bladder. The urethra is like the finish line leading to the exit! Where’s the exit?

Fun Fact Since our bladder can store urine our urinary system never stops working! In the past hour your urinary system made about 30 milliliters or 1 fluid ounce of urine! That’s about how much cold syrup you take when you’re sick.

Why Filter? Outside of Kidney Inside of Kidney Why do kidneys filter our blood? That’s where all the nutrients are. When we digest food, the nutrients are brought across our stomach’s lining and into the blood. The blood is pumped throughout the body, traveling to every organ to drop off needed nutrients as well as oxygenated blood.

Filter How? How do kidneys filter? The kidney’s functional unit is called the nephron. The red in the bottom left picture is a blood vessel bringing in blood rich with nutrients that need to be filtered. The blood vessel is intimately connected to the nephron’s tubes. As blood gets initially poured into the nephron, nutrients will be absorbed across the nephron’s tubes back into the blood vessel.

There are sensors in every nephron that detect the levels of nutrients and water. When the body does not have enough water, nephrons will absorb water back into the blood flow. If the body has too much water, the nephron will let the excess water travel down the nephron tubes and turn into urine to be excreted out as waste.

The Nephron’s Helper The podocyte, is a cell in kidneys that help filter due to their special structure. They have intricate branches called the primary processes or arms with tiny projections branching off called secondary processes or feet. Neighboring podocytes will line up their arms and feet leaving tiny slits through which blood with have to flow through. These slits are so small only small molecules can pass through.

Urine Color clear yellow When our urinary system does not work properly we see changes in urine’s color. dark This is why doctors take urine samples when we visit the hospital to check our urinary system is working fine. If urine is clear, you are hydrated. You are drinking lots of water and the excess water dilutes the color of urine making it clear. If urine is yellow, you are dehydrated. There is not a lot of extra water being filtered out so the urine is yellow. If urine is dark and cloudy, this indicates something is wrong with the kidney and it is not filtering correctly.

Let’s Review! ? Kidney! Ureter! ? ? Bladder! Urethra! ?

Different Kidneys for Different Animals They look different but they still function the same!

The End!