科学素养与生活应用·英语30篇（2）

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趋磁细菌如何利用地磁场导航

Magnetotactic bacteria build internal chains of magnetite crystals that act like microscopic compass needles.
These crystals align passively with Earth’s magnetic field lines, guiding movement toward optimal oxygen levels.
In northern hemispheres, they swim downward along field lines into sediments with less oxygen.
Each crystal is perfectly sized—about fifty nanometers—to stay single-domain and magnetically stable.
Electron tomography shows how cells rotate the whole chain to adjust direction smoothly.
Researchers harvest these bacteria to create biocompatible contrast agents for medical MRI scans.
They thrive in ponds and estuaries where oxygen gradients change rapidly with tides.
Unlike animals, they lack nerves or brains—yet achieve navigation through pure physics.
Synthetic versions now guide drug carriers to tumors using external magnetic fields.
This demonstrates how life harnesses planetary forces at the smallest observable scale.

听 → 读 → 学表达 → 懂 → 今天会说这一句 → 跟读录音 → 自己说一句。

Each crystal is perfectly sized—about fifty nanometers—to stay single-domain and magnetically stable. 每颗晶体尺寸精准——约50纳米——以保持单磁畴结构和磁稳定性。
Unlike animals, they lack nerves or brains—yet achieve navigation through pure physics. 与动物不同，它们没有神经或大脑，却仅靠纯粹物理机制实现导航。
Synthetic versions now guide drug carriers to tumors using external magnetic fields. 人工合成版本现已利用外部磁场引导药物载体靶向肿瘤。

这篇中文题目最接近哪一句？趋磁细菌如何利用地磁场导航一次学校运动会的通知一份超市购物清单

课文第一句的意思更接近？趋磁细菌在体内形成磁铁矿晶体链，如同微观指南针。今天学校放假了。请把窗户打开。

这一课主要在讲什么？（看英文标题） How Magnetotactic Bacteria Navigate Using Earth’s Magnetic Field How to cook noodles A maths worksheet

Each crystal is perfectly sized—about fifty nanometers—to stay single-domain and magnetically stable.

Each crystal is perfectly sized—about fifty nanometers—to stay single-domain and magnetically stable.

第一版：录下来、回听、再听标准音。系统打分以后再加。

用今天的表达，自己说一句。

例子：Each crystal is perfectly sized—about fifty nanometers—to stay single-domain and magnetically stable.