seen the basic difference between a living and a non- living thing and some of the characteristics

看到了生物和非生物之間的基本區別和一些特徵。

shown by living organisms. So today we will be looking at the 1st characteristic

生物體所表現出來的。所以，今天我們要研究的是第1個特徵。

in detail i.e the composition of an organism The trees in the forest the fish in the riverthe

詳解即生物體的組成 森林裡的樹 河裡的魚兒

birds in the sky the worm in the soilthe tiger in the jungle the cactus in the desert your

天空中的鳥兒 淤泥中的蟲子 叢林中的老虎 沙漠中的仙人掌 您的

class mate in fact any living thing on this planet is made up of cells which are known

同學其實這個星球上的任何生物都是由細胞組成的，這些細胞被稱為是

to be the building blocks of a living thing. Many many cells come together to form a living

是一個生命體的構件。很多很多的細胞聚集在一起，形成了一個活的

organism. Besides this, some organisms like bacteria

生物體。除此之外，一些生物如細菌

are made up of only one cell. One celled organism is all together an individual itself which

是由只有一個細胞組成的。一個細胞的生物體共同是一個獨立的個體，它的特點是

can perform all the functions like any other multi-cellular organism.

可以像其他多細胞生物體一樣執行所有功能。

Every living being performs various functions during its entire lifespan like respiration,

每個生物在其整個生命週期中都會執行各種功能，比如呼吸。

digestion, excretion, reproduction etc. the body has specific organs to carry out these

消化、排洩、生殖等，身體有特定的器官來完成這些工作。

functions. These organs are made up of various types

功能。這些器官是由各種類型的

of tissues; and tissues are nothing but a group of cells. So in short we can say that

的組織；而組織不過是一群細胞。所以簡而言之，我們可以說

the human body is composed of many cells.Just as bricks form the important part of a building,

人的身體是由許多細胞組成的，就像磚頭是建築物的重要組成部分。

cells make up an organism. So we can say that cells are the basic fundamental unit of life.

細胞組成了一個生物體。所以我們可以說，細胞是生命的基本基本組織、部門。

In 1665, Robert Hooke discovered cells. He observed dead cells within the cork of the

1665年，羅伯特-胡克發現了細胞。他觀察到了軟木塞內的死細胞。

bark of a tree using an old basic microscope. He observed empty spaces contained by a wall

用老式的基本顯微鏡觀察樹皮。他觀察到一堵牆所包含的空隙

and named them cells because they resembled small compartments.

並把它們命名為細胞，因為它們像小隔間。

So we can say that what Robert Hooke observed looked something similar to a honeycomb structure.

所以我們可以說，羅伯特-胡克觀察到的東西，看起來類似於蜂窩結構。

We shall take a look at some features of a cell. So lets get started.

我們來看看細胞的一些特徵。所以讓我們開始吧。

No. of cells: Based on the no. of cells an organism can

細胞的數量。根據一個生物體可容納的細胞數量。

either be unicellular or multi cellular. As the word suggests Uni- is one cell and multi is many cells.

要麼是單細胞，要麼是多細胞。顧名思義Uni-是一個細胞，multi是許多細胞。

Shape of a cell: Cells are of various shapes. Majority of them

細胞的形狀。細胞有各種形狀。大多數細胞

are round, spherical and elongated. But you know what gives a cell its shape..???

是圓形、球形和拉長的。但你知道是什麼賦予了細胞的形狀嗎？

Just like a room gets its shape from its walls a cell gets its shape from a cell membrane

就像房間的形狀來自於牆壁一樣 細胞的形狀來自於細胞膜。

which is the outer covering of the cell. Soooo talking about shape of cells u know

這是細胞的外層。談到細胞的形狀，你知道嗎？

a unicellular organism named amoeba has no definite shape it is irregular and it keeps

變形蟲是一種單細胞生物，它沒有確定的形狀，它是不規則的，而且它保持著

changing its shape. In multi-cellular organisms, cells are of

改變其形狀。在多細胞生物體中，細胞是有的。

different shapes. Like for eg. A nerve cell is long and branched in structure while a

不同的形狀。像例如，神經細胞是長而支的結構，而一個

red blood cell (rbc) is spherical and concave.

紅細胞(rbc)是球形的，凹形的。

Size of a cell:

細胞的大小。

Cells are very tiny in size and are not visible by the eye. Hence to view them we use a microscope

細胞的大小非常微小，肉眼無法看到。是以，為了觀察它們，我們使用顯微鏡

which is an instrument that magnifies and enlarges the image of a cell.

是一種可以放大細胞影像的儀器。

So did you all know that A smallest cell is 0.1 to 0.5 micrometer which is of a bacteria

那麼大家知道嗎，一個最小的細胞是0.1到0.5微米，這是細菌的。

while the largest cell is 170 mm x 130 mm in size which is the egg of an ostrich.

而最大的細胞大小為170毫米×130毫米，是鴕鳥的蛋。

You must know that the Size of a cell is based on the function it performs and not on the

你必須知道，單元格的大小是基於它所執行的功能，而不是基於單元格中的

size of an organism. sooo.. The nerve cell in an elephant and a rat will be of the same

所以，大象和老鼠的神經細胞也是一樣的。

size.

大小。

A cell has many parts and it contains components which help in the proper functioning of the

一個細胞有許多部分，它包含的成分有助於細胞的正常運作。

cell.

細胞。

We will have a look at them in detail in our next video.

我們將在下一個視頻中詳細瞭解它們。

Till then why dont you all try a small exercise

在那之前，你們為什麼不試著做個小運動呢？

Exercise: try listing all the various types of cells found in a human.

練習：嘗試列出人體內所有的各種類型的細胞。

Until now we have been saying that biology is all about study of life but life is composed

到現在為止，我們一直在說，生物學是研究生命的，但生命是由

of many many cells which come together to form a living organism. Our planet consists

由許多許多的細胞組成，這些細胞聚集在一起形成了一個生命體。我們的地球由

of a vast number of creatures; some may be formed of just one cell like we have seen

有的可能像我們所看到的那樣，只由一個細胞組成。

in an amoeba while others are multi-cellular No of cells can vary depending on the size

在變形蟲中，有些是多細胞的，而有些則是多細胞的，細胞的數量可以根據大小而變化。

of an organism an elephant will obviously have more no of cells compared to a rat but

大象的細胞數顯然比老鼠多，但大象的細胞數卻比老鼠多。

the size of a cell will remain the same as we have seen previously.

單元格的大小將和我們之前看到的一樣。

Also cells have a property of regeneration. Imagine you have got a wound on your knee

同時細胞也有再生的特性。想象一下，你的膝蓋上有一個傷口。

and your skin cells are damaged. But your body has a tendency to regenerate those cells

你的皮膚細胞就會受損。但你的身體有再生的傾向，這些細胞。

on its own. This is the most fascinating property

在自己的身上。這是最吸引人的特性

of cells.

的細胞。

So till the

所以直到

next video follow your curiosity. Do subscribe for more videos on biology.

下一個視頻按照你的好奇心。請訂閱更多關於生物學的視頻。

If you have any questions ask me in the comments below

如果你有任何問題，請在下面的評論中問我。