Shaft骨幹
The shaft itself does not stretch. It gets longer only because the growth plates keep adding bone to its ends.
骨幹本身不會被拉長；它會變長，完全是因為生長板不斷在它的兩端加上新的骨頭。
The Human Body · Lesson 16 · 人體探索 第16課
How Do You Grow Taller?你是怎麼長高的？
Bones grow at soft growth plates near their ends. Watch real 3D leg bones grow from age 2 to 18, look at them the way an X-ray does, and measure how much taller you are in the morning.
骨頭在兩端附近軟軟的生長板長長。看真實的 3D 腿骨從 2 歲長到 18 歲，用 X 光的方式看一看，再量量你早上比晚上高多少。
Big idea · 一句話看懂
You grow taller because cartilage at the growth plates keeps making new bone. When the plates close after the teenage years, growing taller stops.
你會長高，是因為生長板的軟骨不斷變成新的骨頭；青春期過後生長板閉合，就不再長高了。
3D Model · 3D 模型
Watch a Leg Grow 看一條腿長大
Slide the age from 2 to 18, or press play. On the left, a whole skeleton grows beside a ruler. On the right, the thighbone and the shinbone are magnified. The glowing bands near their ends are the growth plates: sparks show new bone being added on the side toward the middle of the bone. Switch to the X-ray view, and the plates turn into dark gaps, just as a doctor sees them. Keep sliding: in the late teens the gaps close, and the bones stop getting longer.
把年齡從 2 歲拉到 18 歲，或按播放。左邊是一整副骨架，站在一把尺旁邊長大；右邊是放大的股骨和脛骨。兩端附近發亮的帶子就是生長板：小火花表示新的骨頭正加在靠近骨頭中段的那一側。切換到 X 光畫面，生長板變成暗色的縫隙，就像醫生看到的那樣。繼續拉：十幾歲後期，縫隙閉合，骨頭就不再變長了。
Loading… · 載入中…
Drag to turn · 拖曳旋轉 Scroll or pinch to zoom · 滾輪／雙指縮放
Leg bones shown about 2× life size · 腿骨大約放大 2 倍
This 3D model needs WebGL, which this browser does not support. The measuring tool and the cards below still work.
這個瀏覽器不支援 WebGL，無法顯示 3D 模型；下方的測量工具和卡片一樣能用。
Morning and evening · 早上和晚上
Arm span · 臂展
—of your height是身高的百分之幾
In one study of 100 children, the average child was about 1.5 cm shorter in the late afternoon than first thing in the morning.有一項研究量了 100 個孩子：到了傍晚，平均比早上剛起床時矮大約 1.5 公分。
- Glowing bands: growth plates (cartilage)
發亮的帶子：生長板（軟骨） - Sparks: new bone being added
小火花：正在加上去的新骨頭 - Thin line: a closed growth plate
細線：已經閉合的生長板 - X-ray view: bone is light, cartilage is dark
X 光畫面：骨頭是亮的，軟骨是暗的
The bones are real adult shapes from BodyParts3D, made smaller for younger ages; a real child's bones are not just small adult bones, and their ends are shaped differently. The growth plates are drawn thicker than they really are, and the sparks are only a sign that bone is being added. The heights are for one example child, not a rule: healthy children of the same age can differ by many centimeters, and they start and finish growing at different times.
骨頭是 BodyParts3D 的真實成人形狀，依年齡縮小；真正的兒童骨頭並不只是縮小的成人骨頭，兩端的形狀也不一樣。生長板畫得比實際厚，小火花只是表示「這裡正在加骨頭」。身高是一個舉例的孩子，不是標準：同年齡的健康孩子可能相差好幾公分，開始和結束長高的時間也不一樣。
Bone models: BodyParts3D, © The Database Center for Life Science, licensed under CC BY 4.0. We selected the bones, simplified the shapes, turned the model upright, and scaled it by age; the growth plates are our own drawing. · 骨骼模型來源：BodyParts3D（日本生命科學資料庫中心，CC BY 4.0 授權）；本站挑選骨頭、簡化形狀、轉正方向並依年齡縮放，生長板為本站自繪示意。
Reading · 英文閱讀
16
Unit 16: How Do You Grow Taller?
Stand against a door frame and ask someone to make a mark above your head. Come back in a year, and the mark will be too low. You have grown. But think about that for a moment. Your bones are as hard as rock. How can something so hard get longer?
靠著門框站好，請人在你頭頂上方畫一條線。一年後再回來，那條線就太低了——你長高了。但請想一想：你的骨頭像石頭一樣硬。這麼硬的東西，怎麼會變長呢？
The answer is that a bone does not stretch. It grows only in special places called growth plates. A long bone, like your thighbone, has a growth plate near each end. A growth plate is a thin layer of cartilage, the same bendy stuff that shapes your ears and the tip of your nose.
答案是：骨頭並不會被拉長，它只在一些特別的地方生長，那些地方叫做生長板。長長的骨頭，例如股骨，兩端附近各有一片生長板。生長板是薄薄的一層軟骨，就是讓耳朵和鼻尖有形狀的那種有彈性的東西。
Inside a growth plate, cartilage cells divide again and again, and the new cells stack up in columns like coins. The oldest cells, on the side toward the middle of the bone, die, and hard bone takes their place. So the plate stays about the same thickness while the bone behind it grows longer, and the two ends of the bone move farther apart. A chemical messenger called growth hormone tells the cartilage cells to keep dividing. Your body releases growth hormone while you are in deep sleep.
在生長板裡，軟骨細胞一次又一次地分裂，新的細胞像硬幣一樣一疊一疊地排成一行行。靠近骨頭中段那一側、最老的細胞會死掉，由堅硬的骨頭取代。所以生長板本身的厚度差不多不變，它後面的骨頭卻越來越長，骨頭的兩端也就越離越遠。有一種叫做生長激素的化學信差，會叫軟骨細胞繼續分裂；身體是在深睡的時候分泌生長激素的。
Doctors can see growth plates on an X-ray. Bone shows up white, but cartilage hardly shows at all, so an open growth plate looks like a dark gap across the bone. Growth plates are the last part of a bone to harden, and they are weaker than the bone around them. That is why a child who falls hard and has a sore, swollen joint should see a doctor.
醫生可以在 X 光片上看到生長板。骨頭在 X 光片上是白色的，軟骨卻幾乎照不出來，所以還沒閉合的生長板看起來就像橫過骨頭的一道暗色縫隙。生長板是骨頭最後才變硬的部分，也比周圍的骨頭脆弱。所以小朋友重重摔一跤之後，如果關節又痛又腫，就應該去看醫生。
Children do not grow at the same speed every year. From about age 2 to age 10, most children grow at a steady pace. Then come a few years of faster growth, which begin at a different age for each child, sometime between about 9 and 15. Later, the growth plates slowly close: bone replaces the last of the cartilage, and only a thin line is left. This usually happens in the middle or late teens. After that, you do not grow taller. Your bones are still alive, though, and they keep rebuilding themselves all your life.
孩子並不是每年都長得一樣快。大約從 2 歲到 10 歲，大部分的孩子以穩定的速度長高；接著有幾年長得比較快，每個孩子開始的年齡都不一樣，大約在 9 到 15 歲之間。之後生長板慢慢閉合：骨頭取代了最後的軟骨，只留下一條細線。這通常發生在十幾歲的中後期。在那之後，你就不會再長高了。不過骨頭仍然是活的，一輩子都在不斷重建自己。
What decides how tall you will be? Mostly the genes you got from your parents. You cannot make your growth plates work faster by stretching or by hanging from a bar. What you can do is give them what they need: enough sleep, food with protein and calcium, some sunshine for vitamin D, and plenty of active play. One more surprise: you are taller in the morning than in the evening. During the day, the soft discs between the bones of your spine get squeezed, and at night they fill out again. Try the measuring tool below the model and see for yourself.
是什麼決定你會長多高？主要是你從父母那裡得到的基因。拉筋或吊單槓並不能讓生長板工作得更快；你能做的，是給它們需要的東西：足夠的睡眠、含有蛋白質和鈣的食物、曬一點太陽來得到維生素 D，還有多多活動、玩耍。還有一個驚喜：你早上比晚上高。白天，脊椎骨之間柔軟的椎間盤被壓扁了；到了晚上，它們又恢復飽滿。用模型下方的測量工具，自己量量看。
Read aloud · 課文朗讀
Questions · 閱讀理解
Where does a long bone grow, and what is that place made of?
It grows at the growth plates near its two ends. A growth plate is a thin layer of cartilage.
Why does a growth plate look like a dark gap on an X-ray?
Because bone shows up white on an X-ray, but cartilage hardly shows at all.
Why are you taller in the morning than in the evening?
Because the soft discs between the bones of the spine get squeezed during the day and fill out again at night.
Words & Phrases · 生字及片語
grow(v.)生長；長大Plants grow fast in the summer.植物在夏天長得很快。height(n.)身高；高度The nurse measured my height at school.護理師在學校幫我量了身高。measure(v.)測量Let's measure the table before we move it.搬桌子之前，我們先量一量吧。cartilage(n.)軟骨Your ears are made of cartilage, so they can bend.你的耳朵是軟骨做的，所以可以彎。growth plate(n.)生長板A growth plate is near each end of the bone.骨頭的兩端附近各有一片生長板。thighbone(n.)股骨；大腿骨The thighbone is the longest bone in your body.股骨是你身體裡最長的骨頭。X-ray(n.)X 光片The doctor looked at an X-ray of my wrist.醫生看了我手腕的 X 光片。adult(n.)成人；大人An adult does not grow taller anymore.大人不會再長高了。
Quick Check · 小測驗
1. Where does a long bone grow longer?
2. What is a growth plate made of?
3. What does growth hormone do in a growth plate?
4. What happens when the growth plates close?
5. According to the reading, when are you tallest?
A Growing Bone · 一根會長大的骨頭
The parts that make you taller 讓你長高的幾個部分
Think of building a tower with blocks: you cannot stretch the blocks, but you can keep adding new ones at the top. A growth plate is the place where the new blocks are made.
把它想成用積木蓋塔：積木不能被拉長，但你可以一直在上面加新的。生長板就是製造新積木的地方。
Growth plates生長板
Thin layers of cartilage. Each long bone has at least two. They are the last part of a bone to harden.
薄薄的一層軟骨，每根長骨至少有兩片；它們是骨頭最後才變硬的部分。
Cartilage cells軟骨細胞
They stack up like coins. The oldest ones die, and bone takes their place.
它們像硬幣一樣疊起來；最老的細胞死掉，由骨頭取代。
Growth hormone生長激素
It travels in the blood to the growth plates. Your body releases it during deep sleep.
它隨著血液來到生長板；身體在深睡的時候分泌它。
Discs of the spine椎間盤
They get squeezed during the day and fill out again at night. That is why you are taller in the morning.
它們白天被壓扁，晚上又恢復飽滿——這就是你早上比較高的原因。
Measure Yourself · 親身測量
Morning and evening 早上和晚上的身高
Measure your height twice in one day, and use the tool below the model to see the difference. You can also compare your arm span with your height.
同一天量兩次身高，用模型下方的工具看看差多少。你也可以比一比臂展和身高。
- ☀️In the morning · 早上Right after you get up, take off your shoes and stand with your heels, back, and head against a wall. Ask a helper to lay a book flat on your head, mark the wall, and measure to the nearest millimeter.一起床就量：脫掉鞋子，腳跟、背和頭貼著牆站好。請人把一本書平放在你頭上，在牆上做記號，量到公釐。
- 🌙In the evening · 晚上Just before bed, measure again in exactly the same way. Enter both numbers in the tool.睡覺前，用完全一樣的方法再量一次。把兩個數字輸入工具裡。
- ↔Your arm span · 你的臂展Stretch your arms out to the sides, and have a helper measure from fingertip to fingertip. For many people, it is close to their height.兩手往兩邊平舉伸直，請人從一邊的指尖量到另一邊的指尖。很多人的臂展和身高差不多。
Myth vs. Fact · 常見迷思
Four things people get wrong 四個常見的誤會
✗ Myth · 迷思Bones grow by stretching all along their length.骨頭是整根一起被拉長的。
✓ Fact · 事實A long bone grows only at the growth plates near its ends. The middle of the bone just gets pushed along.長骨只在兩端附近的生長板生長，中間的部分只是被往外推。
✗ Myth · 迷思Stretching or hanging from a bar makes you grow taller.拉筋或吊單槓可以長高。
✓ Fact · 事實Exercise is good for your bones, but it cannot make the growth plates work faster. Sleep, good food, and time do that job.運動對骨頭很好，但沒辦法讓生長板工作得更快。那是睡眠、好的食物和時間的工作。
✗ Myth · 迷思Everyone has a growth spurt at the same age.每個人都在同樣的年紀突然長高。
✓ Fact · 事實The years of fast growth begin sometime between about 9 and 15. Classmates who are the same age can be at very different points, and all of them can be healthy.長得比較快的那幾年，大約在 9 到 15 歲之間開始。同年齡的同學可能處在很不一樣的階段，而他們都可以是健康的。
✗ Myth · 迷思You are the same height all day.一整天身高都一樣。
✓ Fact · 事實You are tallest in the morning. In one study of 100 children, the average child was about 1.5 centimeters shorter in the late afternoon.早上最高。有一項研究量了 100 個孩子，到了傍晚平均矮了大約 1.5 公分。
Remember It · 記憶口訣
Growing taller in a sentence 一句話記住長高
Bones grow at the ends骨頭從兩端長
Not in the middle, and not by stretching: at the growth plates near each end.
不是從中間，也不是被拉長：是在兩端附近的生長板。
Cartilage first, bone later先是軟骨，後來變骨頭
New cartilage is made, and old cartilage turns into bone. When the cartilage is all gone, growing taller stops.
新的軟骨長出來，舊的軟骨變成骨頭。軟骨全部用完，就不再長高了。
Sleep, eat, play睡飽、吃好、多活動
You cannot rush your growth plates, but you can give them what they need.
生長板催不得，但你可以給它們需要的東西。
Tall in the morning早上比較高
Your spine's discs fill out at night and get squeezed by day. Always measure at the same time of day.
椎間盤晚上恢復飽滿、白天被壓扁。量身高要固定在同一個時段量。
In Chinese · 中文怎麼說
Pulling Up the Sprouts 拔苗助長
More than two thousand years ago, the Chinese thinker Mencius told a story about a farmer who thought the young plants in his field were growing too slowly. So he pulled each one up a little to help it grow. When his son ran out to look, every one of them had withered. The story became the saying 拔苗助長 (bá miáo zhù zhǎng), “pulling up the sprouts to help them grow”: you cannot rush something that needs time. Growth plates work the same way. Here is a language tip, too. In Chinese, 長高 means to get taller and 長大 means to get older. In English, “grow taller” is about your height, but “grow up” is about becoming an adult.
兩千多年前，中國思想家孟子講過一個故事：有個農夫嫌自己的秧苗長得太慢，就把每一株都往上拔高一點，想幫它們長大。他的兒子跑去田裡一看，秧苗全都枯死了。這個故事後來變成成語「拔苗助長」：需要時間的事情，急不得。生長板也是一樣。順便學一個語言小知識：中文的「長高」是變高，「長大」是年紀變大；英文的 grow taller 講的是身高，grow up 講的則是長大成人。
Classroom Activity 1 · 課堂活動一
The Door-Frame Record 門框上的紀錄
You need · 準備材料
- A strip of paper about 2 meters long, taped to a wall or a door frame一張大約 2 公尺長的紙條，貼在牆上或門框上
- A hardcover book, a pencil, and a tape measure一本精裝書、一枝鉛筆和一把捲尺
Steps · 步驟
- Take off your shoes and stand with your heels, back, and head against the paper strip.脫掉鞋子，腳跟、背和頭貼著紙條站好。
- A helper lays the book flat on your head and draws a short line under it. Write the date next to the line.請人把書平放在你頭上，在書底下畫一條短線，旁邊寫上日期。
- Measure again on the first school day of every month, at the same time of day.每個月第一個上學日再量一次，而且要在同一個時段量。
- At the end of the school year, work out how much you grew. In which months did you grow the most?學年結束時，算一算你長高了多少。哪幾個月長得最多？
Teaching tip: keep each student's strip private, and compare each child only with himself or herself. The point is the change, not the number. Height can be a sensitive subject, and children of the same age really do grow at very different times.
教學提示：每個學生的紙條請保密，只拿孩子和自己比較。重點是「變化」，不是數字。身高可能是敏感的話題，而同年齡的孩子長高的時間真的差很多。
Classroom Activity 2 · 課堂活動二
Arm Span and Height 臂展和身高
You need · 準備材料
- A tape measure and masking tape一把捲尺和紙膠帶
- Graph paper, or a large grid on the board方格紙，或是黑板上的一大張方格
Steps · 步驟
- Work in pairs. Measure your partner's height, then the arm span from fingertip to fingertip.兩人一組。先量同伴的身高，再量從一邊指尖到另一邊指尖的臂展。
- Put a dot on the graph: height across, arm span up. Do not write names.在方格紙上點一個點：橫軸是身高，縱軸是臂展。不要寫名字。
- When the whole class has added a dot, look at the pattern. Do the dots make a line?全班都點完之後，看看整體的樣子：這些點排成一條線嗎？
- Draw the line where arm span equals height. Are most dots close to it?畫出「臂展＝身高」的那條線。大部分的點都靠近它嗎？
Teaching tip: this is a first scatter plot. Anonymous dots keep the focus on the pattern instead of on who is tallest. Ask why the two measurements go together: arms and legs both grow at growth plates, under the same growth hormone.
教學提示：這是學生的第一張散布圖。匿名的點讓大家看的是整體趨勢，而不是誰最高。問問學生：為什麼這兩個數字會一起變大？因為手臂和腿都靠生長板生長，聽的是同一種生長激素的指揮。
⚕ Health note · 健康提醒This lesson is for learning about the body. It is not medical advice. Everyone grows at a different time and at a different speed, and being taller or shorter does not make anyone better. Doctors follow each child's growth on a growth chart. If you have a question about your own growth, or if a joint hurts or swells after a fall, tell an adult. Do not use any product that promises to make you taller.本課是認識身體的教材，不是醫療建議。每個人長高的時間和速度都不一樣，長得高或矮並不會讓誰比較好。醫生會用生長曲線追蹤每個孩子的成長。如果你對自己的成長有疑問，或是跌倒之後關節會痛、會腫，請告訴大人。不要使用任何宣稱能讓你長高的產品。