字幕列表 影片播放 列印所有字幕 列印翻譯字幕 列印英文字幕 A building is made up of thousands and thousands of bricks 一棟建築是由上千塊磚頭打造的 likewise, our body is made up of thousands and thousands of 同樣地,我們的身體是由成千上萬個細胞 cells 所組成 What is a cell? Cell is a basic structural 細胞是什麼?細胞是生命的基本構造 and functional unit of life. It is the smallest unit of life 和功能單位。是生命的最小單元 and is often called, the building block of life 常被稱為建構生命的磚塊 the cell was discovered by Robert hooke in 1665 細胞是虎克在1665年發現的 he examined (under coarse, compound microscope) 他檢視(用很粗糙的複式顯微鏡) very thin slices of cork and saw a multitude of tiny pores that he remarked looked 很薄的軟木塞薄片,看見許多小孔隙,他覺得 like the walled compartments 看起來像用牆分隔的小房間 and named them cells 並將之取名為cell(拉丁文:小室) Matthias Jakob Schleiden and Theodore 許萊登和 Schwann proposed cell theory in 1839 許旺在1839年發表細胞學說 which states that all plants and animals are made up of cells 主張所有動植物都是由細胞所組成 and cell is the basic unit of life. 而且細胞是生命的基本單位 unicellular organisms 單細胞生物 they are formed of one cell example amoeba, 由一個細胞組成,舉例:變形蟲 paramecium etc multicellular organisms 草履蟲等等。多細胞生物 they are formed of many cells examples 由多個細胞組成,例如 we human beings etc 我們人類 take a look at the structure of 我們來看看 an animal cell 動物細胞的結構 and now 現在 the structure of a plant cell 植物細胞的結構 let's talk about the components of a cell, cell membrane 我們來談談細胞的組成。細胞膜 it is the outermost elastic covering of the cell 是細胞最外層有彈性的膜 it is made up of lipids and proteins 由脂肪和蛋白質構成 it protects the cell from injury and allows 保護細胞不受傷害並且允許 osmosis it is selectively permeable 滲透作用。有選透性 and allows endocytosis membrane has carrier proteins 並且允許胞吞作用。膜上有運輸蛋白 for active transport 可以傳送物質 cell wall it is a rigid semi elastic 細胞壁:它是一個固態、半流質的 protective and permeable covering present outside the cell membrane 保護性的、可通透的細胞膜外的包覆物 only in plant cells it is made up of cellulose , 只有植物細胞有。它由纖維素、 hemicellulose and pectin . it gives strength to plants 半纖維素、果膠所組成。它讓植物有支撐力 and prevents cell from bursting. 並且防止植物脹破 nucleus it is made up of four 細胞核:它是由四個部分 parts nuclear membrane nucleoplasm 構成,核膜、核質、 nucleolus and chromatin material 核仁和染色質 it controls all cell functions and brings 它控制細胞所有的功能和 about cell differentiation DNA 細胞分化 of chromosome transfers the hereditary characters 染色體的DNA把遺傳因子 from parents to off springs 從親代轉移到子代 cytoplasm it is a Jelly like semi fluid substance 細胞質:它是像果凍般半流質的物質 it is present between cell membrane and nucleus 位於細胞膜和細胞核之間 various cell organelles are present in it 內含各種不同的胞器 cell organelles these 胞器:它們是 are tiny sub-cellular structures specialized to perform specific 比細胞更小的結構,專門執行特定的 functions 功能 and hence are very important as they Carry out important functions 它們非常重要,因為它們執行重要功能 the various cell organelles 各種不同的胞器 and their functions are endoplasmic recticulum, Golgi apparatus 以及它們的功能:內質網及高基氏體 they are membrane-bound vesicles arranged 它們是膜狀囊泡 parallel to each other in tiny sacs 彼此以細小的囊狀平行排列 called cisternae, it helps in formation of cell wall, cell membrane and lysosomes 稱為扁囊。幫助形成細胞壁、細胞膜和溶體 complex sugars may be made from simple sugars in golgi 複雜的醣類可以在高基氏體裡由簡單的醣類形成 apparatus Lysosomes 溶體 they are smaller vesicles covered by single membrane 它們是由單層膜覆蓋的小囊泡 and contain digestive enzymes they are known 內含消化酵素。它們被稱為 as a suicide bags of the cell. they destroy foreign particles 細胞的自殺袋。它們破壞外來粒子 and remove dead and wornout cells Mitochondria 並清除老舊細胞。粒線體 these are rod shaped covered by double membrane 他們是由雙層膜包覆的短棒 it is the site for respiration 是呼吸作用發生的地方 it provides the energy in the form of 它提供能量以 adenosine triphosphate for various chemical ATP的形式給各種化學 activities hence it is called the power house 反應,因此被稱為 of the cell plastids 細胞的發電廠。質體(色素體) these are present only in plant cells 它們只出現在植物細胞 and are of two types: leucoplast and chromoplast 有兩種形式:白色體和雜色體 green coloured plastids called chloroplast contain 綠色的質體稱為葉綠體,含有 chlorophyll and are important for photosynthesis 葉綠素,對光合作用很重要 chromoplast give colour to flowers 雜色體呈色給花 and fruits leucoplast store starch, 果。白色體儲存澱粉 oil and proteins , 油脂和蛋白質 ribosomes 核醣體 this is a structure of a ribosome 這是核醣體的結構 vacuole animal cells have small sized Vacuoles 液胞:動物細胞有小的液胞 while plant cells have very large vacuoles 而植物細胞有非常大的液胞 they are covered by single membrane called tonoplast 它們被單層膜包覆,稱為液胞膜 Turgidity and rigidity of plant cell 植物細胞的膨壓和張力 is due to cells sap. thank you. 是由細胞液決定。謝謝
B2 中高級 中文 細胞 植物 細胞膜 功能 結構 醣類 細胞,細胞的結構和功能 - CBSE NCERT Science (Cells, Cell Structure and Functions - CBSE NCERT Science) 177 28 Study English 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字