So that we look more experienced and intelligent!

它讓我們看起來更有歷練、更聰明。

Naahhh!

錯啦！

Smoking makes people look old because things like cigarettes contain nicotine.

因為香菸中含有尼古丁, 因此抽菸會讓人看起來比較老。

Nicotine is a vasoconstrictor, which means it narrows our blood vessels, restricting the blood supply.

尼古丁是一種血管收縮劑, 這表示它會使我們的血管變窄, 因而限制血液的供應。

When the blood supply is restricted, our cells don't get the required oxygen and nutrients.

血液供應受限時, 我們的細胞就無法得到足夠的氧氣和養分。

As a result, our skin becomes dry and discoloured.

因此, 我們的皮膚就會變得乾燥、無血色。

In addition to this, the collagen and elastin fibers, which keep our skin firm and elastic, begin to break down much faster, leading to saggy and wrinkled skin.

除此之外, 維持皮膚緊緻和彈性的膠原蛋白和彈性蛋白纖維, 會分解地更快, 使皮膚變得鬆弛並形成皺紋。

Also, when we smoke, we purse our lips and squint our eyes.

此外, 抽菸時, 我們會噘起嘴唇, 瞇起眼睛。

Regularly repeating these actions may also cause wrinkles on our lips and around our eyes.

常做這些動作也會使我們的嘴唇和眼睛周圍產生皺紋。

In this way, smoking makes our skin dry, saggy and wrinkled, thus making us look old.

正因如此, 抽菸使我們皮膚乾燥、鬆弛、長皺紋, 讓我們看起來比較老。

Why is snow white?

雪為什麼是白色的？

'Cause it applies fairness cream!

因為用了美白霜！

No!

錯！

Sunlight or white light is a combination of all visible colors of light.

陽光或白光是由所有可見的顏色組合而成。

When light falls on an object, it may absorb some colors of light and reflect the remaining colors.

當光線落在物體上時, 它可能會吸收光的某些顏色並反射其它顏色。

The colors which are reflected by an object make up its color.

物體反射的顏色構成了該物體的顏色。

For example, when light falls on an apple, it absorbs all other colors except red.

例如, 光線落在蘋果上時, 它會吸收紅色以外的所有顏色。

Apple reflects red color, making it appear red.

蘋果因反射紅色而呈現紅色。

When light falls on coal, it absorbs all colors and does not reflect any color.

光線落在煤炭上時, 它會吸收所有的顏色, 不反射任何顏色。

Hence, coal appears black to us.

因此, 煤炭呈現黑色。

Really?

真的嗎？

I didn't know that!

我之前都不知道！

Now, snow does not absorb any colors of light and reflects all of them equally.

雪不會吸收任何顏色的光, 而是均勻地反射所有的顏色。

As the combination of all colors of light is white light, snow appears white to us.

由於白光是所有顏色的組合, 雪在我們眼中是白色的。

Topic: Anaerobic Respiration

主題：厭氧呼吸作用

What is the cause of muscle cramps?

造成肌肉抽筋的原因是什麼？

Excess sleep!

過度睡眠！

Nooo!

不對！

Respiration is a process in which the cells of our body produce energy.

呼吸是我們身體細胞產生能量的過程。

Normally, our cells respire aerobically.

通常我們的細胞會進行有氧呼吸。

In this process, the glucose, with the help of oxygen, is completely broken down to produce energy, water and carbon dioxide.

在此過程中, 葡萄糖在氧氣的幫助下被完全分解, 以產生能量、水和二氧化碳。

Is this energy then used for all our activities?

然後變成我們進行所有活動運用的能量？

Indeed!

沒錯！

However, during heavy exercise, our body cannot deliver enough oxygen to the cells of our muscles.

然而, 從事劇烈運動時, 我們的身體不能輸送足夠的氧氣給肌肉細胞。

Hence, in such situations, anaerobic respiration helps us to produce some energy temporarily and thus continue our work.

因此, 在此情況下, 厭氧呼吸作用能幫我們暫時產生一些能量, 以讓我們持續運動。

In anaerobic respiration, the glucose is partially broken down in the absence of oxygen to produce comparatively less amount of energy.

在厭氧呼吸作用中, 葡萄糖在缺氧的情況下被部分分解, 產生相對較少的能量。

And a waste product called lactic acid.

還有乳酸廢棄物。

Now, one of the most prominent reasons for the muscle cramps is the accumulation of this lactic acid.

肌肉抽筋最主要的原因之一就是乳酸的累積。

Topic: Sublimation

主題：昇華作用

Why do mothballs disappear over time?

樟腦丸為什麼過一段時間就會消失？

Wow!

哇！

You have a nice collection of clothes!

你有好多好看的衣服！

But have you kept mothballs to protect them?

但你有放樟腦丸來保護它們嗎？

Yeah, yeah!

當然！

I had kept them a few months back below these clothes!

幾個月前我在這些衣服下面放了一些。

Hey!

欸！

Where did the mothballs go?

樟腦丸跑去哪兒了？

I placed them right here!

我明明把它們放在這裡！

Did you steal them?

你把它們偷走了嗎？

No, no!

沒有！

I haven't stolen anything!

我什麼都沒有偷！

Mothballs disappear over time.

樟腦丸過一段時間就會消失。

Do you know why?

你知道為什麼嗎？

It is because of a process called sublimation.

因為所謂的昇華作用使然。

During sublimation, a solid on heating, converts directly into vapor without passing through the intermediate liquid state.

在昇華的過程中, 固體受熱後不會變成液體, 而是直接轉化為蒸氣。

Don't lie!

少騙人！

How is that even possible?

這怎麼可能？

See, I also hid a burger here many days ago!

你看, 幾天前我也在這裡藏了個漢堡。

It did not disappear!

它可沒有消失！

Oh, gross!

真噁心！

Just throw that burger in the dustbin!

把漢堡丟進垃圾桶裡吧！

Not all substances sublimate.

不是所有物質都會昇華。

Mothballs are made up of naphthalene.

樟腦丸由萘組成。

Naphthalene has very weak intermolecular forces.

萘的分子間拉力很弱。

Because of these weak forces, the mothball, which is made up of naphthalene, sublimates.

因為拉力很弱, 由萘組成的樟腦丸就會昇華。

That is, it changes its state from solid to vapor.

也就是說, 它的狀態從固態變成了氣態。

Now, this vapor is either absorbed by the fabric or it escapes into the atmosphere, causing the mothballs to disappear over time.

這些水蒸氣不是被織物吸收就是逃逸到大氣中, 使樟腦丸經過一段時間後就消失。