Excretion – The Urinary System
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Kidneys excrete wastes from the body as urine
The liver breaks down excess protein and makes urea
The kidneys filter the blood to remove the urea. The urea is dissolved in the urine.
The kidneys also remove excess salt and water from the blood, as well as vitamins.
If wastes are allowed to build up, you would die.
Parts of the urinary system include –
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Kidneys – filter the blood
Ureter – carry urine to the bladder
Bladder – holds urine (about 400mL)
Urethra – carries urine to the outside
There are ______ kidneys, one on each side of the body.
The kidneys remove the waste products from the blood using small filters called ________________.
The waste products now called urine drains into a tube called the ___________ that connects to the
bladder.
The _____________ stores the urine, and when it is full a muscular ring opens up, allowing the urine to go
through the outlet tube called the __________________.
Complete this Crossword
ACROSS
5. Muscle that controls opening the release
of urine from the bladder.
6. A word that refers to the kidney.
7. Tube that transports urine from the
kidney to the bladder.
10. If this substance is found in the urine it
indicates a problem.
11. Compound produced when proteins are
broken down by the liver.
12. Disease that can cause sugar to exit with
the urine.
14. A doctor who specialises in the urinary
system.
15. There are two of these organs that filter
the blood.
DOWN
1. Organs that excrete carbon dioxide from
the body.
2. A doctor who specialises in diseases of the
kidney.
3. This excreted liquid contains water, salts,
vitamins and urea.
4. This can be excreted by the skin.
8. Tube that transports urine out of the
body.
9. There are a million of these filtration units
in each kidney.
13. Where urine is stored before it is
expelled.
Colour and label the urinary system.