The Body's Strange Machinery

Science and Technology · 10 questions

The engineering inside you that nobody explained at school.

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1. What stops stomach acid from digesting the stomach itself?

   1. A very thick muscle wall
   2. The acid being too weak
   3. A coating of bile
   4. A constantly renewed mucus layer
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   D) A constantly renewed mucus layer

2. Which muscle is striated, works involuntarily, and is remarkably resistant to fatigue?

   1. Skeletal muscle
   2. Smooth muscle
   3. Cardiac muscle
   4. Connective tissue
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   C) Cardiac muscle

3. Which of these is among the fastest-renewing tissues in the human body?

   1. The lining of the intestine
   2. The muscle of the heart
   3. The neurons of the brain
   4. The enamel of the teeth
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   A) The lining of the intestine

4. What actually triggers the urge to take a breath?

   1. Falling oxygen in the blood
   2. Rising carbon dioxide in the blood
   3. The lungs emptying completely
   4. A timer in the brainstem
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   B) Rising carbon dioxide in the blood

5. A newborn has around 300 bones and an adult 206. What explains the difference?

   1. Some bones dissolve away
   2. The counting method differs
   3. Cartilage is discarded
   4. Bones fuse together as we grow
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   D) Bones fuse together as we grow

6. Which structure inside your cells carries its own DNA, inherited from your mother?

   1. The ribosome
   2. The Golgi apparatus
   3. The mitochondria
   4. The lysosome
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   C) The mitochondria

7. Roughly how long does the eye need to adapt fully to darkness?

   1. About 10 seconds
   2. 20 to 30 minutes
   3. About 2 minutes
   4. About 3 hours
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   B) 20 to 30 minutes

8. Tooth enamel is the hardest tissue in the body, yet it cannot repair itself once damaged.

   1. True
   2. False
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   A) True

9. A person can live without a spleen.

   1. True
   2. False
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   A) True

10. Sweetness is detected only by the tip of the tongue and bitterness only by the back.

    1. True
    2. False
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    B) False