B2 中上級 2841 タグ追加 保存
There's a factory inside you that weighs about 1.4 kilograms
and runs for 24 hours a day.
This is your liver, the heaviest organ in your body,
and one of the most crucial.
This industrious structure simultaneously acts as a storehouse,
a manufacturing hub,
and a processing plant.
And each of these functions involve so many important subtasks
that without the liver, our bodies would simply stop working.
One of the liver's main functions is to filter the body's blood,
which it receives in regular shipments from two sources:
the hepatic artery delivers blood from the heart,
while the hepatic portal vein brings it from the intestine.
This double delivery fills the liver with nutrients,
that it then sorts, processes and stores
with the help of thousands of tiny internal processing plants,
known as lobules.
Both blood flows also deliver the oxygen that the liver needs to function.
The blood that is received from the intestine
contains carbohydrates, fats,
and vitamins and other nutrients dissolved in it
from the food you've consumed.
These must be processed in different ways.
In the case of carbohydrates,
the liver breaks them down and converts them into sugars
for the body to use as energy when the filtered blood is sent back out.
Sometimes the body has leftovers of nutrients
that it doesn't immediately require.
When that happens, the liver holds some back,
and stacks them in its storage facility.
This facility works like a pantry
for future cases when the body might be in need of nutrients.
But the blood flowing into the liver isn't always full of good things.
It also contains toxins and byproducts that the body can't use.
And the liver monitors these strictly.
When it spots a useless or toxic substance,
it either converts it into a product that can't hurt the body
or isolates it and whisks it away,
channeling it through the kidneys and intestine to be excreted.
Of course, we wouldn't consider the liver a factory
if it didn't also manufacture things.
This organ makes everything from various blood plasma proteins
that transport fatty acids and help form blood clots,
to the cholesterol that helps the body create hormones.
It also makes vitamin D and substances that help digestion.
But one of its most vital products is bile.
Like an eco-friendly treatment plant,
the liver uses cells called hepatocytes
to convert toxic waste products into this bitter greenish liquid.
As it's produced, bile is funneled into a small container below the liver,
called the gallbladder,
before being trickled into the intestine
to help break down fats, destroy microbes, and neutralize extra stomach acid.
Bile also helps carry other toxins and byproducts from the liver
out of the body.
So as you can see,
the liver is an extremely efficient industrial site,
performing multiple tasks that support each other.
But such a complex system needs to be kept running smoothly
by keeping it healthy
and not overloading it with more toxins than it can handle.
This is one factory we simply can't afford to shut down.


【TED-Ed】What does the liver do? - Emma Bryce

2841 タグ追加 保存
稲葉白兎 2014 年 11 月 30 日 に公開
  1. 1. クリック一つで単語を検索


  2. 2. リピート機能


  3. 3. ショートカット


  4. 4. 字幕の表示/非表示


  5. 5. 動画をブログ等でシェア


  6. 6. 全画面再生


  1. クイズ付き動画


  1. クリックしてメモを表示

  1. UrbanDictionary 俚語字典整合查詢。一般字典查詢不到你滿意的解譯,不妨使用「俚語字典」,或許會讓你有滿意的答案喔