Unit 3: The Cell (Lecture Notes)

emit-The cell pant-1 Cell's ane the building blocks of all living organisms, → Acell y the fundamentare enit of structure and finetion. It ly the mit of all living system. either plants on animals →The term "Dell" owa introduce by Robert Hooke in 1665. → Deffination: "Ceu y a unit of bio bilalogicae activitieg delimited by a semi- permiable mentssane and caproice of self reproduction! force of others living system: In a medium mai's seatures of cou thenry as known today : modern call theory: modern living anyanim ane composed of ceus. cell is the structural and fimetiones en't of living organisme.. 3. All cens anise from the pre-existing call of the similar kind. 4. The chemiare composition and Similan. meta brority of all cens are basically 5. The function of an organim as a ahole y the out come of the activities and interaselfions of the constituent cells. 6. Each cell antains generally a centrally placed nuclears and many cell onepresies T. ceu Vy the store house of genetic information and vehicle of Cell 8. its expression. Energy flow occurs who within Cell- (iv) origin of eukaryotic cells (Endosymbiotic theory): Symblagenesis or endosymbiotic therry, isan evolutionary theory of the origin of eukanyaotre ceus fitom prokaryotre onefanitnes, finst atticulated in 1985 and 1910. by the Russian botanist konstantin Substantia and su Lynn mangulis 1967- with nicrobiologycal evidence by →t holds had the organellets organeves distingcchisuishing eulkanyatre evalued though Symbiogenesis of Prokaryotes (bacteria & anchaza). indivisual Single cened The tweory holde that mitochondria, Plastids suchas Chioroplast and posing ather organelles of eukaryotic celus represent in in free liv sldesymbiosis Prokaryotes taken one inside the other The evidence in support of the theory that mitochondria and Chieve plast anose toom bacteria and lepane bacteria! か New mitochonahsia and plastids are formed only through a process Similar to bi birany Assion that occur in bacteria. 2. Transpored protein callest porins. ane in the membrane of mitochondria and Chioso plast's and are also found in balterial cell membrane. 3 A merabreane lipid, candiallpisi candiallpis is exclusively found in the inner membrane of mitochondria and bacterial cell membrane. 4. Both mitochondria and plastids contesto single cinevlan DNA that y different form cell nucleus, but Similan to that of bacteria barth in size & Structure. (5.) Genome comparison indicate the cyanobacteria contributed to the genette onigin of plastids." 6. The ritosomes of Chioroplast and mitochondria ane like those foond in beceteria (705). T Several enxyme and transport system of mitochondola ost of bacteria. ane simbianto to thaste • muchos the internal structure, and blochemistry of plastids for example the presence of thylakoids and encorophyll molecules, ane very similar to that of cyano bacteria, phylogenetic estimates constructed with bacteria, plastids, and eukaryotic genomes suggested plant cell would (Parch-2) mosting closery related to that plastids ane mosto Defination', cell wall y a thick regids Cyanobacteria. Semi- elastic, semi- transparent, protective covering of the plant cell which Surrounded the outside of y not completely dead active. A plasma membrane. cell wall non-elving, it y metaborically نورد → The thickness of cell coll veinies from 0.1 to 10 km. I chemical Composition cellulose y the majore chemical Component of the cell wal Comprising of about 33% of al vegetable matters. others ane: CLipids 2.5-9%% (is coater Bo-6070 (y) microfibrilu=20-40% Hemi cellulose-5-15% (iny peetly substance 2-3%. (viⅱ) Depositions = 0-0.25% proteing 1-2% Structure ~ The plant cell wall y multi-layered and consists ols upto three section from the outermost layer of the cell wall, these layer are identified as the middle lamella, primery while all plant cells & secondary cell wall & felmi have a middle Cell wall. cell cwall y protest not all home sec Secondary coll axell. and primeroy cells • Middle lamella) This outer con axul layer contains poly sarcharides lamella and Called pectins. resping the cell walls of adjacent → pectins aid in reis adhesion by helping. cells to bind to ane another. •Primaryseall) This layers y formed between the middle lamella and plasma membrane in growing plant cells. Tickness -(61-3.0m) →t y primerrily composed of cellulase microfibring contained lager-ethe matrix of hemicellulose fibers & pectin. within a polysaccharides. →The primary cell was provides the strengtes and flexibility needef allow cell growth. cell wall → this layere formed between the primary cell membrane in some plant caus asace & plasma fon wall has stopped dividinge and growing, cken day foreng It may thicken This a Secondary cell wall. f&pports rigid layer strengthens any. ypports the cele. → once the →In addition to cellulose cay cualls cantein lignin. and hemicellulose, some secondary → Lignin strengthens the cellware & aids in water conductivig In plants Vasculare tissue ceus. → the proteins are of two types: Integrasproteins and peripheral proteins. → Integrace proteso imbenched th the lipid bilayer anel provides fon chounels. But peripheral proteins are attached to the membrane Sun-ferre ere. y week bonds like hydrogen bands, vandercwaals forces Th They periforem many membrane function ive Intraction betwee marym the membrane and the cytoskeleton components. The plasma membrane y composed of 4 majore types of lipids live phospholipids, glycolipids, neturae lipids and stercols. Complex proteins any glycoprotein and complex lipid arce glyce lipid & phospholipids. Carbohydrates →Canbo ame polysaccharides. aus mainey oligosaccharides, alcony. coith + Structhese atyantzortion of plasma membrane) 3 Membrane hoursport paexobrane dorang pont, refers to a no. of mechaniky that regulate the passage of solute such as long& @maer molecules through biologycae membranes alichace lipid bilayer that contains protein embeded them. passage through the membrane y due to its →The regulation of passe Selective percmeability. → the movement of most folute turroughs the membrane ane mediated by membrane transport protein. Types of membrane thorny perf cellulare membrane pokesstwo key qualities! ① The ane Semipermiable (only certain materials may freely cross-lange & charged substances cane typically bracke ane selective (membrane protem may regulate the passage I material that con't freely Cros. → movement of materials altross a biologyeol merobrane may eithere activay or passively & fucilately, so their ane three types of membrane transport Suchay! Active transport @pasive transport @facitated transport. Susten passive-transport passive transport involves the movement of a concentration. concentrsection). Matertece colong gradient (high concentration to lover! Berase materials are moving down a Concentsation gractient, it does not require the expenditure of energy (ATP hydrolysis). There ane three main types of passive transport: Simple diffusion) movement of smalt on lipophilic Molecures (zie Og, саден). smosis) movement of water molewies (dependenton Solute concentration) facilate diffusion :-) move mend of lange on Changed Molecues via membrane proteins (de ions, suctaseek) Active Transport →Active transport involves the movement of matericus against graellant (Row concentratten to concentration graella high Because Materials • the gondient ture I gradient energy. anem m it requins the expenditure! 2. e Hip hydrolysis) There ane two math types of active trang port Suchos . primary (dinect) active transporet y.) . It involves the dineet Use of metabolic en energy de (Atp hydrolysis) to medicate transport." Secondary (indineed) transport:) Involves coupling the molecule with another moving an electrochemical gradient. along an