AP Bilgy Ch. 4 Cellular Structure and Functin 4.1Cellular Level f Organizatin Cell Thery: Name Cell Size Large cells - Small cells EK 2.A.3b: Surface area- t- vlume ratis affect a bilgical system s ability t btain necessary resurces r eliminate waste prducts. Learning Objectives: (AP EXAM) LO 2.6 The student is able t use calculated surface area- t- vlume ratis t predict which cell(s) might eliminate wastes r prcure nutrients faster by diffusin. LO 2.7 Students will be able t explain hw cell size and shape affect the verall rate f nutrient intake and the rate f waste eliminatin. Activity: Surface area t vlume Ratis Wrksheet Evidence f student learning is a demnstrated understanding f each f the fllwing: 1. As cells increase in vlume, the relative surface area decreases and demand fr material resurces increases; mre cellular structures are necessary t adequately exchange materials and energy with the envirnment. These limitatins restrict cell size. 2. The surface area f the plasma membrane must be large enugh t adequately exchange materials; smaller cells have a mre favrable surface area- t- vlume rati fr exchange f materials with the envirnment. 4.2 Prkarytic Cells Prkarytic cells are placed in tw taxnmic dmains: Bacteria Archaea Dmains are structurally similar but bichemically different The Structure f Prkarytes Occur in three basic shapes:
Prkarytic Cell Shape http://highered.mheducatin.cm/sites/007337525x/student_view0/exercise9/prcarytic_cell_ shapes.html Cell Envelpe includes: Plasma membrane - Cell wall - (EK 2.B.1.c Cell walls prvide structural bundary as well as a permeability barrier fr sme substances t the internal envirnment.) Glyccalyx - Prkarytic Cytplasm and Appendages Cytplasm Nucleid Plasmids Appendages Flagella Fimbriae Cnjugatin pili Bacteria Lcmtin http://highered.mheducatin.cm/sites/007337525x/student_view0/exercises_35-90/bacterial_lcmtin.html 4.3 Intrducing Eukarytic Cells Cells cntain: Much larger than prkarytic cells Origin f Eukarytic Cells: http://highered.mheducatin.cm/sites/9834092339/student_view0/chapter4/animatin_- _endsymbisis.html
Essential knwledge 1.B.1: Organisms share many cnserved cre prcesses and features that evlved and are widely distributed amng rganisms tday. Structural evidence supprts the relatedness f all eukarytes. Use endsymbisis as justificatin. Essential knwledge 2.B.3: Eukarytic cells maintain internal membranes that partitin the cell int specialized regins. Internal membranes facilitate cellular prcesses by minimizing cmpeting interactins and by increasing surface area where reactins can ccur. Membranes and membrane- bund rganelles in eukarytic cells lcalize (cmpartmentalize) intracellular metablic prcesses and specific enzymatic reactins. Eukarytic Cells: Organelles Tw classes f rganelles: Endmembrane system Energy related rganelles Animal Cell Anatmy and Plant Cell Anatmy see pages 68 and 69 4.4 The Nucleus and Ribsmes The Nucleus The Nucleus Chrmatin cntains Dark nuclelus -
Ribsmes Are the site f Cmpsed f - May be lcated: 4.5 The Endmembrane System Series f Cnsists f: Endplasmic Reticulum and Glgi Apparatus http://bcs.whfreeman.cm/thelifewire/cntent/chp04/0402002.html Endplasmic Reticulum A system f - Rugh ER Studded with ribsmes n cytplasmic side Prtein anablism - Mdifies and prcesses prteins Smth ER
The Glgi Apparatus Lyssmes Within cell Exprt frm cell (secretin, excytsis) Prduced - Cntain - Digestin Recycling f - Sme genetic diseases Lysssmes http://highered.mheducatin.cm/sites/0072495855/student_view0/chapter2/animatin lyssm es.html Endmembrane System Summary Prteins prduced in rugh ER and lipids frm smth ER are carried in vesicles t the Glgi apparatus. The Glgi apparatus mdifies these prducts and then srts and packages them int vesicles that g t varius cell destinatins. Secretry vesicles carry prducts t the membrane where excytsis prduces secretins. Lyssmes fuse with incming vesicles and digest macrmlecules. Endmembrane System Mdel See p. 74
4.6 Other Vesicles and Vacules Perxismes Hwever Vacules Txic Brken dwn t water & O2 by Stre Others very specialized - Plants cells typically have a central vacule Functins in: 4.7 Energy- Related Organelles Chlrplasts (See p. 76 fr Structure) Inner membrane Why? Suspended in Green due t chlrphyll Fund ONLY in - Serve as the site f Captures light energy -
Phtsynthesis Synthesizes Makes wn fd Energy- pr cmpunds Only - Mitchndria (See p. 77 fr Structure) Cntain - Inner membrane surrunds Matrix Break dwn carbhydrates Invlved Prduce Origin f Mitchndria and Chlrplasts http://www.sumanasinc.cm/webcntent/animatins/cntent/rganelles.html 4.8 The Cytskeletn Actin filaments Intermediate filaments Micrtubules Actin Filaments (see p. 78 fr actin peratin mdel) Extremely
Dense - Supprt - Intracellular traffic cntrl Functin in - Imprtant cmpnent in Intermediate Filaments Rpe- like Vary in nature Frm tissue t tissue Functin: Supprt - Cell- cell junctins- Micrtubules (See p. 78 fr micrtubule peratin mdel) Hllw cylinders made f tw glbular prteins Interacts with Centriles Lcated in Oriented Separate May give rise t basal bdies f cilia and flagella Cilia and Flagella (See p. 81 fr mdel f structure f flagellum) Very different frm Lcated n uter cvering f In eukarytes, - Cilia mve Flagella mve