The gas exchange system and airways · 气体交换系统与气道
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| trachea/trəˈkɪə/ | 气管 | qì guǎn |
| bronchi/ˈbrɒŋkaɪ/ | 支气管 | zhī qì guǎn |
| bronchiole/ˈbrɒŋkɪəʊl/ | 细支气管 | xì zhī qì guǎn |
| alveoli/ˈælvɪɒli/ | 肺泡 | fèi pào |
| cartilage/ˈkɑːtɪlɪdʒ/ | 软骨 | ruǎn gǔ |
| ciliated epithelium/ˈsɪlɪeɪtɪd ˌepɪˈθiːlɪəm/ | 纤毛上皮 | xiān máo shàng pí |
| mucus/ˈmjuːkəs/ | 黏液 | nián yè |
| goblet cell/ˈɡɒblət sel/ | 杯状细胞 | bēi zhuàng xì bāo |
| squamous epithelium/ˈskwɒməs ˌepɪˈθiːlɪəm/ | 扁平上皮 | biǎn píng shàng pí |
Getting oxygen to the blood
- Your body must take in oxygen and get rid of carbon dioxide.
- Air travels down a branching set of airways to tiny sacs deep in the lungs.
- Special tissues keep those airways open and clean.
把氧气送到血液
- 你的身体必须摄入 氧气 并排出 二氧化碳。
- 空气沿一组分支的气道行进到肺深处的微小囊。
- 特殊的组织保持那些气道打开和清洁。
The path of air
- Air goes: down the trachea 气管 (windpipe) → into two bronchi 支气管 (one per lung) → into many bronchioles 细支气管 → into tiny alveoli 肺泡.
- Each alveolus is wrapped in a network of capillaries, bringing air and blood very close together.
The human lungs, where gas exchange takes place across millions of alveoli.
空气的路径
- 空气走:沿 气管(trachea)(风管)→ 进入两个 支气管(bronchi)(每肺一个)→ 进入许多 细支气管(bronchioles) → 进入微小的 肺泡(alveoli)。
- 每个 肺泡 被一个 毛细血管 网络包裹,使空气和血液非常靠近。

人的肺,气体交换在数百万个肺泡上进行。
Explore the airways · 探索气道
Tap each part. Air branches from the trachea down to the tiny alveoli, where gas exchange happens. · 点击每个部分。空气从气管分支向下到微小的肺泡,气体交换在那里发生。
Put the airways in the order air passes through them. · 把气道按空气通过它们的顺序排列。
Air flows: trachea → bronchi → bronchioles → alveoli (where exchange happens). · 空气流动:气管 → 支气管 → 细支气管 → 肺泡(交换发生的地方)。
Airway tissues
| Tissue | Function |
|---|---|
| cartilage 软骨 | C-shaped rings hold the airway open |
| ciliated epithelium 纤毛上皮 | cilia beat to sweep mucus 黏液 up to the throat |
| goblet cells 杯状细胞 | make mucus that traps dust and microbes |
| smooth muscle | contracts to narrow the airway |
| elastic fibres | stretch on breathing in, recoil to push air out |
| squamous epithelium 扁平上皮 | very thin alveolus lining → short distance to cross |
A section through an airway wall: cartilage, smooth muscle, and the ciliated epithelium with goblet cells
**Lung tissue under the microscope: a small airway in the centre, ringed by the lacy network of thin-walled alveoli **
气道组织
| 组织 | 功能 |
|---|---|
| 软骨 | C 形环把气道保持 打开 |
| 纤毛上皮 | 纤毛摆动把 黏液 扫到喉咙 |
| 杯状细胞 | 制造困住灰尘和微生物的 黏液 |
| 平滑肌 | 收缩以 缩窄 气道 |
| 弹性纤维 | 吸气时伸展,回弹以推出空气 |
| 鳞状上皮 | 很薄的肺泡内衬 → 穿过的距离短 |

气道壁的一个切面:软骨、平滑肌,以及带杯状细胞的纤毛上皮

显微镜下的肺组织:中央是一个小气道,周围环绕着薄壁肺泡的网状结构
The C-shaped rings of cartilage in the trachea and bronchi: · 气管和支气管中 C 形的软骨环:
Cartilage supports the airway, keeping it open as air pressure changes during breathing. · 软骨支撑气道,在呼吸时气压变化时保持它打开。
Match each airway feature to its job. · 把每个气道特征与它的工作配对。
Cartilage supports, goblet cells trap, cilia sweep, and the thin alveolar lining speeds diffusion. · 软骨支撑,杯状细胞困住,纤毛扫,薄的肺泡内衬加快扩散。
The squamous epithelium of the alveoli is very thin and flat because this: · 肺泡的鳞状上皮很薄很扁,因为这:
A thin, flat lining means a short diffusion distance, so gas exchange is fast. · 一层薄而扁的内衬意味着短的扩散距离,所以气体交换很快。
Bronchioles have no cartilage; their walls contain smooth muscle instead. · 细支气管没有软骨;它们的壁含有平滑肌代替。
The smallest airways lose the cartilage and have smooth muscle, which can narrow them. · 最小的气道失去软骨,有能缩窄它们的平滑肌。
Keeping the lungs clean
- Goblet cells (and mucous glands) make mucus that traps dust and microbes you breathe in.
- The cilia then sweep that mucus up to the throat, where it is swallowed.
- Together they protect the lungs from dirt and infection.
Ciliated epithelium and goblet cells keep the airways clean
保持肺清洁
- 杯状细胞(和黏液腺)制造困住你吸入的灰尘和微生物的 黏液。
- 纤毛 然后把那些黏液扫 到喉咙,在那里它被吞下。
- 它们一起保护肺免受污垢和感染。

纤毛上皮和杯状细胞保持气道清洁
The tiny hair-like structures that beat to sweep mucus up out of the lungs are called ______. · 摆动以把黏液向上扫出肺的微小毛发状结构叫做 ______。
Cilia beat in a wave, moving the dirt-laden mucus up to the throat to be swallowed. · 纤毛以波浪状摆动,把带污垢的黏液移到喉咙被吞下。
You've got it
- air path: trachea → bronchi → bronchioles → alveoli (wrapped in capillaries)
- cartilage holds airways open; smooth muscle narrows them; elastic fibres recoil
- goblet cells make mucus (traps dust/microbes); cilia sweep it up to the throat
- squamous epithelium = thin alveolus lining → short diffusion distance
你掌握了
- 空气路径:气管 → 支气管 → 细支气管 → 肺泡(被毛细血管包裹)
- 软骨 把气道保持打开;平滑肌 缩窄它们;弹性纤维 回弹
- 杯状细胞 制造黏液(困住灰尘/微生物);纤毛 把它扫到喉咙
- 鳞状上皮 = 薄的肺泡内衬 → 短的扩散距离