特别注意一下中心叶脉附近的区域。

Pay particular attention to the areas right near the center vein.

youdao

叶脉结构较为复杂，主脉发达。

The structure of leaf vein is complicated.

youdao

我们在叶子上可以看到叶脉。

We can see veins on a leaf.

youdao

而一切基于叶脉。

And veins are the basis of it all.

youdao

叶脉密度标志着树叶在这个网状结构中投入了多少。

Vein density is a sign of how much a leaf has invested in the network.

youdao

他们发现叶脉循环既可提高效率，又可减轻损害。

They found that as well as improving efficiency, they also help to ameliorate damage.

youdao

叶脉中木质部比重越大，越有利于水分的传输。

Large proportion of xylem benefit to the water transfer.

youdao

叶脉中木质部比重越大，越有利于水分的传输。

Large proportion of xylem benefit to the water transfer.

youdao