The chlorophyll breaks down when this happens.

这时叶就分解了。

They contain chlorophyll, which helps create various colors.

他们所含的叶颜色深浅不同。

To understand why, think back to photosynthesis and chlorophyll.

想知道什么，请回想一下光合作用和叶。

It's formulated with chlorophyll to reduce redness and pore size while also soothing the skin.

它采用叶配方，可缓解红肿和孔，同时舒缓肌肤。

Because chlorophyll is green, and plants are full of it.

因叶是色的，而植物充满了叶。

Chloroplasts are found only in plant cells and contain chlorophyll.

叶体仅存在于植物细胞内，而且含有叶。

While chlorophyll is there, it's there and it's green.

叶在哪儿产生，哪儿就会是色的。

Chlorophyll is also the substance that gives plants its green colour.

叶也是使植物呈现色的物质。

Nitrogen is needed for proteins, DNA and the chlorophyll that let plants perform photosynthesis.

氮是蛋白质、DNA和让植物进行光合作用的叶所必需的。

And this is where chlorophyll really shines.

这才是叶真正闪光的地方。

They're just hidden by the abundance of green chlorophyll during the warmer months.

它们只是在温暖的月份被大量的色叶掩盖。

In photosynthesis, chlorophyll absorbs energy from sunlight and creates sugar to feed the plant.

在光合作用中，叶从阳光中吸能量，并合成糖类供养植物。

When chlorophyll molecules absorb light, some of their electrons become excited.

当叶分子吸阳光时，一部分电子被激发起来。

You see in the fall leaves stop their food making process and the chlorophyll declines.

你看，在秋天，树叶的光合作用减弱，叶减。

They're able to transfer the sun's energy and create a chemical known as chlorophyll.

树叶能够转移太阳的能量，产生一种被称叶的化学物质。

Plant cells also contain chloroplasts which are filled with a chemical called chlorophyll.

植物细胞还包含叶体，里面充满了一种叫做叶的化学物质。

In contrast, chlorophyll fluorescence is a direct measure of photosynthetic activity.

相比之下，叶荧光能直接地测量光合作用活动。

And the molecule that did the light-absorbing? Chlorophyll! Maybe.

是什么分子吸了光线呢？可能是叶。

As the chlorophyll in a tree's leaves begins to wane, these underlying pigments become visible.

随着树叶中的叶开始减，这些潜在的色变得可见。

And not all parts of a leaf always have the same amount of chlorophyll.

叶子的所有部分并非拥有相同数量的叶。