Chapter 7 Cell Structure and Function PDF
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This document appears to be a chapter from a general biology textbook, specifically focused on cells. It includes a glossary of terms and diagrams of cell structures.
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P108 普通生物學共筆 General Biology 1 Chapter7: Cell Structure and Function 上課日期:2019.9.16 共筆學藝:陳衍儒 陳裕仁 審稿:郭亭萱 組員:周艺涵 林亭 江佳真 蔡佳恩 蘇郁晴 李義昕 邱薏恩 廖宣品 吳紹帆 KMU P108 普生共筆 Chapter7: Cell Structure and Function...
P108 普通生物學共筆 General Biology 1 Chapter7: Cell Structure and Function 上課日期:2019.9.16 共筆學藝:陳衍儒 陳裕仁 審稿:郭亭萱 組員:周艺涵 林亭 江佳真 蔡佳恩 蘇郁晴 李義昕 邱薏恩 廖宣品 吳紹帆 KMU P108 普生共筆 Chapter7: Cell Structure and Function By 周艺涵 Outline 本章大綱 ⚫ Comparison of prokaryotic and eukaryotic cells (原核與真核細胞的比較) ⚫ Organelles(胞器): Nucleus(細胞核) Ribosomes(核糖體) 備註:Ribosomes are not membrane bounded →not considered organelles 核糖體無膜包圍,故不稱做胞器 Endoplasmic Reticulum(内質網 ) Golgi(高基氏體 ) Lysosomes(溶體) Mitochondria(粒線體)and Chloroplasts(葉綠體) Peroxisomes 過氧化體 ⚫ Cytoskeleton(細胞骨架) ⚫ Extracellular components(細胞外的組成成分) ⚫ Cell-Cell: intercellular junctions(細胞與細胞之間的連結) ⚫ Studying tools (研究工具) 1 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Glossary Actin 肌動蛋白 Endoplasmic Reticulum 內質網 Adhesion 附著 Enzyme 酵素 Amoeboid 變形蟲 Eukaryotic cell 真核細胞 Anabolism 合成代謝 Exocytosis 胞吐作用 Autophagosome 自噬小泡 Extracellular matrix(ECM) 胞外基質 Autophagy 自體吞噬 Fibronectin 纖維連接蛋白 Axon terminal 軸突末端 Flagella 鞭毛 Biosynthetic 生物合成的 Flagellum 鞭毛 Carbohydrate 碳水化合物 Fluorescence 螢光 Catabolism 分解代謝 Glycoprotein 醣蛋白 Catalase 過氧化氮酵素 Golgi apparatus 高基氏體 Cell division 細胞分裂 Gap junction 間隙型連接 Cellular motility 細胞運動性 Hydrolyze 水解 Cellular respiration 呼吸作用 Hydrophilic 親水性的 Centriole 中心粒 Hydrophobic 疏水性的 Centrosome 中心體 Integrin 整合蛋白 Chloroplast 葉綠體 Intermediate filament 中間絲 Chromosome 染色體 Lipid bilayer 脂雙層 Cilia 織毛 Lipid 脂質 Cis face 高基氏體接收側 Lysosome 溶體 Cisternae 扁囊 Macromolecule 大分子 Collagen 膠原蛋白 Matrix 基質 Contractile vacuole 伸縮泡 Microfilament 微絲 Cytoplasm 細胞質 Microtubule 微管 Cytoskeleton 細胞骨架 Microvillus 微絨毛 Cytosol 細胞質液 Mitochondria 粒線體 Dynein 纖毛內蛋白 Motor protein 動蛋白 Doublet 成對物 Myosin 肌凝蛋白 Endocytosis 胞吞作用 Non-cellulose 非纖維素多醣類 Endomembrane System 內膜系統 Nuclear envelope 核膜 2 KMU P108 普生共筆 Chapter7: Cell Structure and Function Nuclear lamina 核纖維蛋白 Nucleic acid 核酸 Nuclear pore 核孔 Nucleus 細胞核 Nucleolus 核仁 Undulate 波動 Organelle 胞器 Vacuole 液胞 Oxidase 氧化酶 Vesicle 囊泡 Oligosaccharide 寡糖 Pectin 果膠 Peroxisome 過氧化體 Phagocytosis 吞噬作用 Photosynthesis 光合作用 Pinocytosis 胞飲作用 Plasma membrane 細胞膜 Plasmodesmata 原生質絲 Polypeptide 多肽 Polysaccharide 多醣 Prokaryotic 原核的 Protein Dynein 動力蛋白 Pseudopod 偽足 Replicate 複製 Resolution 解析度 Secretion 分泌 Specimen 樣本 Sperm 精子 Stain 染色 Synaptic 突觸的 Synthesize 合成 Tight junction 緊密型連接 Tonoplast 液泡膜 Trans face 高基氏體的輸出側(shipping side) Tubulin 微管蛋白 3 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Diagram of animal cell(動物細胞簡圖) 4 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Plasma Membrane(細胞膜) ⚫ A selective barrier(選擇性屏障) ⚫ Allows sufficient passage of nutrients and waste 允許特定的養分與廢物通過 (膽鹼) (磷酸根) (甘油) 備註:不同的極性基使細胞膜有所差異。 Outside of cell Carbonhydrate side chain(醣類支鏈) Inside of celll Hydrophilic region (親水端) Hydrophobic region (疏水端) Hydrophilic region Proteins 負責訊息傳遞 region Phospholipid(磷脂) 5 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ The Nucleus: Genetic information 細胞核:基因訊息 ⚫ Double membrane(脂雙層)with nuclear pores(核孔)that encloses nucleus(核仁) ⚫ The nuclear envelope(核膜) : A double memebrane ⚫ Nuclear pore(核孔): Regulating the entry and exit of proteins and RNAs 核孔負責調控蛋白質與 RNA 的進出 ⚫ Nuclear lamina(核纖層): A network of intermediate filaments(中間絲)that maintain the shape of the nucleus. 中間絲構成的網狀結構,用以維持細胞核的形狀 ⚫ Nucleolus(核仁):Assembles ribosomal RNA (rRNA) 組裝核糖體 RNA 補充:若細胞缺乏核纖層(Nuclear lamina),只會影響細胞核構型,不 影響遺傳物質。 核孔 核膜 核仁 染色質 核質 核纖層 核籃 細胞質絲 核孔 6 KMU P108 普生共筆 Chapter7: Cell Structure and Function By 林亭 ◆ Ribosomes: Protein Factories in the Cell ⚫ Ribosome(核糖體) The engine of translation( 轉譯) Carry out protein synthesis 執行蛋白質合成 A complex(複合物)comprising several different ribosomal RNA and as many as 83 proteins Ribosomes:核糖體 Cytosol:細胞質 Free Ribosomes:游離型核糖體 Bound Ribosomes:附著型核糖體 Large Submit:大單元 Small Submit:小單元 TEM:透射電子顯微鏡 ⚫ Types Free ribosomes( 游離型核糖體): Are suspended in the cytosol and synthesize proteins 懸浮於細胞質中並合成蛋白 Most proteins are made on free ribosomes Bound ribosomes(附著型核糖體): Are attached to the outside of endoplasmic reticulum or nuclear envelope. Synthesize membrane protein, lysosome protein, secretion protein 附著在內質網或核膜的外側,合成膜蛋白、水解酶(e.g.酵 素)、分泌蛋白(e.g.抗體)。 7 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ The endomembrane system regulates protein traffic and performs metabolic functions 內膜系統掌控蛋白質運輸及執行代謝功能 ⚫ Components of the endomembrane system(內膜系統的組成) Nuclear envelope(核膜) Endoplasmic reticulum(內質網) Golgi apparatus(高基氏體) Lysosomes(溶體) Vacuoles(液泡) Plasma membrane(細胞膜) ⚫ These components are either continuous or connected via transfer by vesicles 這些物質彼此之間藉由直接接觸或是囊泡來運送 ◆ The Endoplasmic reticulum: Biosynthetic Factory 內質網:生物合成的工廠 ⚫ Smooth ER, which lacks ribosomes Synthesizes lipids(脂質): oils, steroids(荷爾蒙前驅物), membrane phospholipids(磷脂膜) Metabolizes carbohydrates, alcohol Stores calcium ions 儲存鈣離子:用於肌肉&生理功能 Detoxifies poison and drug: adding hydroxyl group →making more soluble and easier to flush from the body 解毒:添加羥基於其上,使其增加水溶性以加速代謝排出體外 8 KMU P108 普生共筆 Chapter7: Cell Structure and Function ⚫ Rough ER, which contains ribosomes Produces proteins and membranes, which are distributed by transport vesicles 產生蛋白質和細胞膜,並由運輸囊泡傳遞出去 Secret protein production: glycoprotein 產生分泌蛋白質:醣蛋白 Membrane factory for the cell 合成細胞膜的工廠 Smooth ER:平滑內質網 Rough ER:粗糙內質網 Nuclear Envelope:核膜 ER Lumen:內質網內腔 Cisternae:扁囊;內腔 Ribosomes:核糖體 Transport Vesicle:運輸囊泡 Transitional ER:過渡內質網 9 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ The Golgi Apparatus: Shipping and Receiving Center (高基氏體:傳送和接收的中心)(教授比喻郵局XD) ⚫ Receives vesicles from RER 接收來自粗糙內質網的運輸囊泡 ⚫ Cisternae: a flattened membranous sac 扁囊:一種扁平膜狀囊袋 ⚫ Functions: Modification(修飾): modification of the oligosaccharide portion of glycoproteins 修飾蛋白質的寡糖部分 補充:高基氏體由一堆扁囊所構成,但並不相連,所以和內質網有所區 別。囊泡就像郵差,運送信件(蛋白質)前往目的地。 Manufacture(製造): pectin and other non-cellulose polysaccharides(plant cells) 製造膠質和非纖維素多醣類 高基氏體有 cis face(接收 面)和 trans face(運送 面),各有不同酵素,可逐 步產生和改造產物,加工過 程中,則由囊泡在扁囊間傳 送,最後產物包在囊泡中與 細胞膜融合而離開。 Secretion:分泌物 Transport Vesicle:運輸囊泡 Saccules:球囊 Trans Face:運送面 Cis Face:接收面 Glogi Apparatus:高基氏體 10 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ 細胞膜傳輸 奪諾貝爾醫學獎 ⚫ 2013 諾貝爾生理學講或醫學獎由 James Rothman、 Ra n d y S ch e km a n 、 T h o m a s S u e d h o f 以「調控囊泡傳輸(vesicle) 的機制,囊泡運輸為體內細胞主要的運輸系統」的發現獲獎 ⚫ 3 位得獎主解決了細胞如何組織其運送系統之謎。每個細胞都是生產 與輸出分子的工廠。這些分子在細胞周圍以囊泡來運送。發現了規 範細胞如何在正確時間把貨物運送到正確位置的分子原則。 體內細胞的正常運作取決於在正確的時間、正確的地方獲得正確的分 子。一些分子,像是胰島素,需要從細胞輸出,而其他分子則需要待在 胞內的特定位置。已知在胞內有些分子是需要被裝入運輸囊泡的(如圖 上藍色區域所示),但這些囊泡如何正確交付貨物仍然是一個謎。 11 KMU P108 普生共筆 Chapter7: Cell Structure and Function By 江佳真 ◆ Lysosomes: Digestive Compartments(溶小體:消化隔間) ⚫ Hydrolytic enzymes(内含水解酶) ⚫ Digesting all kinds of macromolecules 消化各種大分子 Work best at pH5 Hydrolyze proteins, fats, polysaccharides, and nucleic acids 會水解蛋白質,脂質,多醣類,核酸 ⚫ For programmed destruction of cells in multicellular organisms 在多細胞有機生命體中負責調控細胞程序性凋亡 ⚫ Diseases Tay-Sachs diseases(戴薩克斯症或家族性黑矇痴呆症) 因分解脂質的酵素缺少或失活性導致脂質堆積於腦中造成神經 系統退化 Lysosomal storage disease(溶小體儲積症 LSD) 由溶小體的缺陷所引起,通常缺乏代謝脂質、醣蛋白或黏多醣 的酵素,導致大分子堆積於細胞中,造成細胞死亡 Pompe disease; acid maltase deficiency: (龐貝氏症;酸性麥芽糖酵素缺乏症) Deficiency of the lysosomal acid alpha-glucosidase enzyme. Accumulation of glycogen in the lysosome 缺乏酸性 α-葡萄糖苷酶,肝糖無法分解而堆積在溶體,導致漸 進式的肌肉無力與呼吸困難,台灣研發第一個解藥:Myozyme 12 KMU P108 普生共筆 Chapter7: Cell Structure and Function ⚫ Digestion type 消化形態 Phagocytosis(吞噬作用):Endocytosis(胞吞作用)其中ー種 Fuse with food vacuoles, formed when a food item is brought into the cell 當食物分子被帶進細胞時,會和溶小體膜融合並形成食泡 Hydrolytic enzymes digest food Lysosome contains active particles hydrolytic enzymes 溶體內的水解酶消化損壞胞器 Lysosome Digestion Food vacuole fuses with lysosome 溶小體和含損壞胞器的囊泡融合 13 KMU P108 普生共筆 Chapter7: Cell Structure and Function ⚫ Autophagy(自噬作用):回收細胞內有機物質的機制 Recycling of worn-out organelles through endocytosis 透過胞吞作用回收損壞的胞器 Balance between anabolism and catabolism 在合成代謝和分解代謝間達成平衡 The accumulation of autophagic vesicles(自噬囊泡的累積) 1. Parkinson's(帕金森氏症) 2. Alzheimer’s(阿茲海默症) 3. Huntington’s(亨丁頓氏舞蹈症) 溶體包含兩個受損胞器 粒線體碎片 過氧化體碎片 溶小體和含損壞胞器的囊泡融合 溶小體內的水解酵素消化損壞胞器 Lysosome fuses with vesicle Hydrolytic enzymes digest containing damaged organelle organelle components Lysosome Digestion Vesicle containing damaged mitochondrion 含損壞胞器的囊泡 (b) Autophagy: lysosome breaking down damaged organelle 14 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ 補充:Autophagy pathway(自噬作用途徑) 日本科學家大隅良典因「自噬機制的發現」獲得 2016 諾貝爾生醫獎。 自噬體前驅構造 自噬溶小體 自噬體 人類你已經唸 1/4 了 還有 3/4 加油~ 15 KMU P108 普生共筆 Chapter7: Cell Structure and Function By 蔡佳恩 ◆ Autophagy degrades lipid droplets(油滴自噬) ⚫ 原理: 彎月狀吞噬泡包圍油滴後,凹陷端關閉形成自噬體吞入油滴,自噬 體再與溶體(內含水解酶)結合形成自噬溶小體,在自噬溶小體內 將油滴分解為脂肪酸。脂肪酸最終進入粒線體並產生 ATP。 Lipophagy:脂肪分解 phagophore:吞噬泡,彎月狀雙層構造 lipid droplet:脂肪滴 autophagosome:自噬體 autolysosome:自噬溶小體 fatty acid:脂肪酸 oxidation:氧化作用 mitochondria:粒線體 16 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ 補充:Autophagy induction(如何引起細胞自噬) ⚫ Environmental stress responses 環境壓迫(正面) Accumulation of protein aggregates(聚集體) damaged organelles(胞器) intracellular(細胞內的)bacteria and viruses infection ⚫ Oncogenic stress 癌化因子刺激(負面) Aberrant cellular proliferation(異常的細胞增殖): recycling of ATP and maintain cellular biosynthesis(生物合成)and survival 目的為協助癌細胞維持高度平衡,讓細胞不過勞死。 ⚫ 此為病毒抑制細胞自噬之例 Modulation of the host autophagy pathway by human tumor viruses 17 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Vacuoles(液胞): Diverse Maintenance Compartments(隔間) ⚫ Food vacuoles:Are formed by phagocytosis(吞噬作用) ⚫ Contractile(伸縮) vacuoles:Pump excess water out of protist (原生生物) cells ⚫ Central vacuoles: In plant cell Hold reserves of important organic compounds(化合物) and water 細胞質 液胞膜 Nucleus 葉綠體 18 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ The endomembrane system(內膜系統) ⚫ 過程 1. 核膜,粗糙內質網與平滑內質網相連 2. 蛋白質和細胞膜在粗糙內質網製造,再由囊泡運至高基氏體 3. 高基氏體擠壓出運輸囊泡和其他形成溶體與液泡的囊泡 4. 溶體和其他囊泡融合以消化食物 5. 運輸囊泡把蛋白質運至細胞膜以進行分泌 6. 細胞膜藉由與囊泡融合而擴張;細胞則分泌出蛋白質 cis Golgi:高基氏體接收面 trans Golgi:高基氏體釋出面 19 KMU P108 普生共筆 Chapter7: Cell Structure and Function By 蘇郁晴 ◆ 補充:Exosomes (外泌體;胞外體) ⚫ Small intracellular membrane-based vesicles with a lipid bilayer membrane 有單層膜的囊泡 Containing various types of lipids and proteins For distant intercellular communication:by extracellular vesicle (EV ) 透過胞外囊泡 EV 進行細胞間遠距離聯絡 ⚫ Three types of EVs: 外泌體 微泡 凋亡小體 20 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ 補充:Application of exosomes 外泌體應用 ⚫ Exosomes as therapeutic drug carriers and delivery vehicles across biological membranes 外泌體作為治療藥物以及橫跨生物膜間的運送載體 Non-immunogenic in nature due to similar composition as body’s own cells 由於與身體自身細胞的成分相似,不易讓身體發生免疫反應, 甚至可以通過 BBB *血腦屏障(BBB) :血管與大腦之間的「障壁」,除氧氣、二 氧化碳、血糖外,大分子物質如藥物、蛋白質等無法通過。 *血腦屏障(BBB)Blood-brain barrier 薑黃素 21 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Energy transformers ⚫ Mitochondria(粒線體) Generating ATP from the catabolism of sugars, fats, and other fuels in the presence of oxygen. 有氧情況下,透過分解醣、脂肪或其他燃料來產生 ATP respiratory chain(呼吸鏈) oxidative phosphorylation(氧化磷酸化作用) 粒線體 膜間隙 外膜 內膜 粒線體皺褶 粒線體基質中的游離核糖體 粒線體基質 ⚫ Chloroplasts(葉綠體) Photosynthesis(光合作用) convert solar energy to chemical energy and synthesize new organic compounds from CO2 and H2O 將太陽能轉換成化學能以及用二氧化碳跟水合成出新的有機化 合物 ⚫ Both organelles have small quantities of DNA that direct the synthesis of the polypeptides produced by these internal ribosomes. (Mitochondria: 13 proteins, 2 ribosomal RNAs and 22 transfer RNAs) 粒線體及葉綠體皆有少量 DNA 影響其內部核糖體所產生的多肽鍊合成。 22 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ 補充:Mitochondrial dysfunction in amyotrophic lateral sclerosis (ALS)肌萎縮性脊髓側索硬化症,漸凍人 ⚫ Approximately 20% of fALS (familial ALS) displays mutations in the SOD1 gene encoding superoxide dismutase 1. (SOD1) gene 約有 20%左右的遺傳性 ALS 患者有 SOD1 基因編碼的突變現象 Location: intermembrane space of mitochondria 位置:粒線體的模間隙 SOD1 interacts with kinesin and dynein motor complexes SOD1 與驅動蛋白和動力蛋白複合體相互作用 Axon Terminal 軸突末端 軸突末 端 23 KMU P108 普生共筆 Chapter7: Cell Structure and Function By 李義昕 ◆ 補充:粒線體 DNA 與細胞核 DNA 的比較 *Leber Hereditary Optic Neuropathy 雷伯氏遺傳性視神經萎縮症:屬於母系遺傳 24 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Peroxisomes: Oxidation(過氧化體:氧化作用) contain enzymes that transfer hydrogen from various substrates to oxygen 含有可將氫從各種受質轉移至氧的酵素 Produce hydrogen peroxide (H2O2) and convert it to water 製造過氧化氫並將之轉化為水 Specialized peroxisomes, glyoxysomes, convert the fatty acids in seeds to sugars, an easier energy and carbon source to transport 植物中特化的過氧化體,又稱為乙醛酸循環體,能將種子內的脂肪 酸轉化為醣類,是一種較簡單的能量來源和碳源運輸形式 葉綠體 過氧化體 粒線體 25 KMU P108 普生共筆 Chapter7: Cell Structure and Function By 周艺涵 ◆ Peroxisomal diseases(過氧化酶疾病) ⚫ Oxidase(氧化酶) Use molecule oxygen to oxidize organic substances 利用微粒氧分子氧化有機物 e.g. Oxidize fatty acid for generating precursors for biosynthesis pathway 氧化脂肪酸來產生有機物以完成合成作用 ⚫ Catalase(過氧化氫酵素) 2H2O2 (hydrogen peroxide) 2H2O +O2 ⚫ Liver and Kidney cells Toxic molecule are degraded(有毒分子分解) ⚫ Human genetic disease: X-linked adrenoleukodystrophy (ALD) 腎上腺腦白質退化症 Defective in oxidation of very long chain fatty acids 超長鏈脂肪酸在氧化上有缺陷 ALD gene: encodes the peroxisomal membrane protein that transports into peroxisomes an enzyme required for the oxidation of long chain fatty acid ALD 基因:轉錄出過氧化小體包膜蛋白,此蛋白可運送可氧化長 鏈脂肪酸的酵素進入過氧化小體 血液裡面非常長鏈飽和脂肪酸過高,堆積於腎上腺皮質與大腦白質,進而 侵蝕人體腦神經系統的「髓鞘質」。 26 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Cytoskeleton(細胞骨架) ⚫ A network of fibers extending throughout the cytoplasm 在細胞質中延伸的纖維網狀構造 ⚫ Organize structure and activities in the cell 組織細胞內結構及活動 provides anchorage for many organelles and cytosolic enzymes 為多種胞器和酵素分子提供停泊處 微管 微絲 27 KMU P108 普生共筆 Chapter7: Cell Structure and Function By 邱薏恩 ◆ Roles of the Cytoskeleton(細胞骨架) ⚫ Support Give mechanical support to the cell. Remarkable strength and resilience(彈性). It can be quickly dismantled(拆解) and reassembled. ⚫ Motility Changes in cell location & movement of cell parts. Require interaction of the cytoskeleton with motor proteins. Examples: 1. Neurotransmitter(神經傳遞物) molecules migrate to the tips of axons(軸突). 2. Plasma membrane forms food vacuole(食泡). Receptor for motor protein interacts with motor proteins (動力蛋白受體) (與動力蛋白相互作用) (a) Motor proteins that attach to receptors on organelles can “walk” the organelles along microtubules or, in some cases, microfilaments. 有動力蛋白附著的囊泡可沿著微管行走,在某些例子中是微絲 28 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Centrosomes and Centrioles 中心體和中心粒 ⚫ The centrosome(中心體) Location: near nucleus microtubule-organizing center(微管組成中心粒) Contains a pair of centrioles(中心粒) 1. During cell division the centrioles replicate 2. Centrioles: nine sets of triple microtubules arranged in a ring 中心體的縱向截面 中心體的橫向截面 29 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Components of the Cytoskeleton ⚫ Microtubules(微管) Structure : Hollow rods constructed from tubulin(微管蛋白). Diameter: 25nm with 15-nm lumen. Protein subunits: Tubulin, a dimer consisting of α-tubulin and β- tubulin. Main functions: 1. Maintenance of cell shape 2. Cell motility 3. Chromosome movements in cell division 4. Organelle(胞器) movements ⚫ Intermediate Filaments(中間絲) Structure: Fibrous protein coiled into cables. Diameter: 8~12nm Protein subunits: several different proteins. Main Functions: 1. Maintenance of cell shape 2. Anchorage(停泊所) of nucleus 3. Formation of nuclear lamina(核纖層) ⚫ Microfilaments(微絲) Structure: Two intertwined strands of actin. Diameter: 7nm Protein subunits: Actin Main functions: 1. Maintenance of cell shape 2. Changes in cell shape 3. Muscle contraction 4. Cytoplasmic streaming in plant cells 5. Cell motility 6. Division of animal cells 30 KMU P108 普生共筆 Chapter7: Cell Structure and Function 31 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Cilia and Flagella(纖毛和鞭毛) ⚫ Cilia Extends from cells that are held in place as part of a tissue layer. They can more fluid over the surface of the tissue. Non-motile cilia acts as a signal-receiving antenna(天線). Usually occur in large numbers on the cell surface ⚫ Flagella It has an undulating motion. The sperm of animals, algae, and some plants have flagella. ◆ The protein dynein(動力蛋白) ⚫ Attached along each outer microtubule doublet. ⚫ Is responsible for the bending movements of cilia and flagella. ⚫ Powered by ATP, the dynein arms of one microtubule doublet grip the adjacent doublet, push it up, release, and then grip again 微管上的動力蛋白以消耗 ATP 來抓住附近的微管,藉此推動,放 開、推動,放開。 ⚫ A cilium or flagellum, two adjacent doublets(鄰近的微管雙聯體) cannot slide far because they are physically restrained by proteins, so they bend 32 KMU P108 普生共筆 Chapter7: Cell Structure and Function By 廖宣品 ◆ Microfilaments (Actin Filaments)微絲(肌動蛋白絲) ⚫ Are found in microvilli 微絨毛 ⚫ protein actin 肌動蛋白 Microvillus 微絨毛 Plasma membrane Microfilaments (actin filaments) *微絨毛中有微絲 ◆ Microfilaments that function in cellular motility 作用在細胞運動中的微絲 ⚫ 收縮原理:內含微絲,可做 cellular motility(細胞變形) ⚫ 其中的微絲 contain the protein myosin(肌凝蛋白)和 actin(肌動蛋白) Myosin: interdigitate(相互交叉) with the thinner actin fibers Muscle cell Actin filament 肌動蛋白絲 Myosin filamen 肌凝蛋白絲 Myosin arm 肌凝蛋白臂 (a) Myosin motors in muscle cell contraction. 肌動蛋白在肌細胞中收縮 33 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Working ⚫ Amoeboid movement(變形蟲運動) Involves the contraction of actin and myosin 牽涉微絲中的肌動蛋白和肌凝蛋白 微絲分布變化產生延伸的偽足 Cortex(皮質)(outer cytoplasm):gel with actin network(具肌動蛋白的凝膠體) Inner cytoplasm: sol with actin subunits (具肌動蛋白次單元的溶膠體) Extending pseudopodium(延伸偽足) ⚫ Cytoplasmic streaming(細胞質流) This speeds the distribution of materials within the cell 肌凝蛋白連接胞器沿著微絲移動,來牽引著胞器和帶動細胞內 物質朝著相同方向移動 Nonmoving cytoplasm(gel) (固定胞質) Streaming cytoplasm(sol) Chloroplast(葉綠體) (流動胞質) Parallel actin filaments (平行的肌動蛋白絲) Cell wall 34 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Intermediate Filaments(中間絲) ⚫ Support cell shape(維持細胞形狀) ⚫ Fix organelles in place(固定胞器) ⚫ Are more permanent fixtures of the cytoskeleton than are the other two classes(細胞骨架中最穩定持久的) 35 KMU P108 普生共筆 Chapter7: Cell Structure and Function By 吳紹帆 ◆ The Extracellular Matrix (ECM) of Animal Cells 動物細胞的胞外基質 ⚫ Covered by an elaborate matrix, the ECM 動物細胞被緻密的胞外基質包覆 ⚫ ECM function 1. Support(支持) 2. Adhesion(黏著) 3. Movement(移動) 4. gene regulation(基因調控) ◆ ECM structure: Is made up of glycoproteins and other macromolecules 胞外基質的結構:由醣蛋白和其他大分子構成 (多醣分子) (碳水化合物) (核蛋白) (蛋白多醣分子) ◆ Integrins transmit signals between the ECM (Fibronectin) and the cytoskeleton(整合蛋白於 ECM 核細胞骨架間傳遞信號) ⚫ regulate cell’s behavior(調控細胞的行為) ※ 1.Collagen(膠原蛋白) :多數動物細胞之胞外基質中最豐富的醣蛋白,與細胞生長、附 著、軟骨組織的彈性有關 2.Integrin(整合蛋白) :橫跨細胞膜,為一端接胞外基質,另一端與微絲結合的膜蛋 白。與細胞訊息、細胞週期之調節、細胞型態以及細胞運動有關。 36 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ ECM multidisciplinary integrated platform 37 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Types of intercellular junctions in animals 動物細胞間的連結類型 ⚫ Tight junctions(緊密型): very tightly pressed against each other, bound together by specific proteins, preventing fluid from moving across a layer of cells. 細胞間由特定蛋白緊密連結,以防液體通過細胞層 ⚫ Desmosomes (細胞間橋體): function like rivets, fastening cells together into strong sheets. 功能跟鉚釘很像,將細胞緊繫成強韌的層面 ⚫ Gap junctions(間隙型): provide cytoplasmic channels from one cell to an adjacent cell by special membrane proteins. 由特定膜蛋白提供細胞質液通道至鄰近細胞 38 KMU P108 普生共筆 Chapter7: Cell Structure and Function ◆ Dengue virus-caused plasma leakage and hemorrhage according to phase of illness 因登革病毒疾病階段所引起的血漿滲漏和出血 ⚫ Cytokine storm is an important factor for the development of severe DENV diseases (vascular leakage) 細胞因子風暴是嚴重 DENV 疾病(血管滲漏)發展的重要因素 共筆 feedback 有任何問題都可以透過這個表單 和我們聯絡! 39