AP BIOLOGY Chapter 6 What You Should Know Already from BIO I Slide shows combined and modified from: http://gbs.glenbrook.k12.il.us/Academics/gbssci/bio/apbio/Lecture/lecture.htm; http://www.explorebiology.com/ http://home.att.net/~tljackson/neville.html

Cell Theory Components All known living things are made up of one or more cells All living cells arise from pre-existing cells by division The cell is the fundamental unit of all living organisms.

CELL MEMBRANE (also called plasma membrane) SEE HOW MEMBRANES FORM PHOSPHOLIPID BILAYER with PROTEINS Hydrophobic tails face in Hydrophilic heads face out Outside of cell Inside (cytoplasm) Cell membrane Proteins Protein channel Lipid bilayer Carbohydrate chains Membrane Image from: © Pearson Education Inc, Publishing as Pearson Prentice Hall; All rights reserved Phospholipid image from: http://bioweb.wku.edu/courses/BIOL115/Wyatt/Biochem/Lipid/P_lipid2.htm

FLUID MOSAIC MODEL Click here to See Fluidity Molecules in cell membranes are constantly moving and changing Animation from: http://www.sp.uconn.edu/~terry/images/anim/fluidmem.gif

CELL MEMBRANES act as boundary selectively permeable ~ gases & hydrophobic molecules can pass through ~ large, ionic, OR polar molecules need help (facilitated diffusion, ion channels, Na+-K+ pump, endocytosis & exocytosis) http://vilenski.org/science/safari/cellstructure/cellmembrane.html http://www.d.umn.edu/~sdowning/Membranes/membraneImages/jpegimages/diffusionmedium.jpg

CYTOPLASM (Between nucleus and cell membrane) Image from: http://faculty.stcc.cc.tn.us/jiwilliams/labprojectsmenu.htm CYTOPLASM (Between nucleus and cell membrane) Includes ORGANELLES- small structures with a specific function CYTOSOL-semi-fluid “goo” Image from: http://vilenski.org/science/safari/cellstructure/cytoplasm.html

NUCLEUS Surrounded by DOUBLE membrane (Nuclear envelope) Image from: http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookCELL2.html NUCLEUS Surrounded by DOUBLE membrane (Nuclear envelope) Nuclear pores- allow molecules in & out Contains DNA Control center Replication (DNA → DNA) Transcription (DNA → RNA)

NUCLEOLUS Produces ribosomal RNA Assembles ribosomes (RNA & proteins) Dark spot in nucleus Produces ribosomal RNA Assembles ribosomes (RNA & proteins) Image from: http://lifesci.rutgers.edu/~babiarz/histo/cell/nuc3L.jpg http://universe-review.ca/I09-08-RNA.gif

DNA CHROMATIN- spread out in NON-dividing cells to access info CHROMOSOMES- condensed in dividing cells for easier transport

Cytoskeleton Network of protein fibers supporting cell shape and anchoring organelles Microtubules Microfilaments

RIBOSOMES Composed of two subunits that join and attach to messenger RNA Made of r-RNA & proteins Site of protein synthesis (~translation)

ENDOPLASMIC RETICULUM (ER) Lipid bilayer continuous with nuclear envelope Smooth ER • no ribosomes • synthesis of lipids • metabolism of carbohydrates • stores calcium • detoxification of drugs and poisons Rough ER • with ribosomes • synthesis of secretory proteins (glycoproteins) • membrane production Image from: http://www.agen.ufl.edu/~chyn/age2062/lect/lect_06/5_10B.GIF

Golgi apparatus (collection of Golgi bodies) “UPS” of cell Modify, sort, & package molecules from ER for storage OR transport out of cell http://vilenski.org/science/safari/cellstructure/golgi.h Image from: http://www.rsbs.anu.edu Image from: http://vilenski.org/science/safari/cellstructure/golgi.h

Animation from: http://www.franklincollege.edu/bioweb/A&Pfiles/week04.html See a Golgi movie

EVERYTHING’S CONNNECTED!

Lysosomes - membrane-bound vesicles containing digestive enzymes Breaks down food unwanted cell parts bacteria helps in APOPTOSIS “programmed cell death” See lysosomes in action:

“PROGRAMMED CELL DEATH” APOPTOSIS Embryo development Cell maintenance Signal to self destruct lost in cancer cells http://www.mgm.ufl.edu/images/bharfe/image3.jpg http://research.yale.edu/ysm/images/78.3/articles-apoptosis-cells.jpg

CENTRIOLES Made of microtubules Appear during cell division in animal cells to pull chromosomes apart

CENTRIOLES/MITOTIC SPINDLE Made of MICROTUBULES (Tubulin) Image from: http://www.coleharbourhigh.ednet.ns.ca/library/organelle_worksheet.htm

MITOCHONDRIA DOUBLE MEMBRANE (inner membrane = cristae) Has own DNA Powerplant of cell ~ site of cellular respiration ~ burn glucose ~ store energy as ATP Images from:

CHLOROPLASTS DOUBLE MEMBRANE Has own DNA http://www.seorf.ohiou.edu/~tstork/compass.rose/photosynthesis/chloro_sun_bathing.gif CHLOROPLASTS DOUBLE MEMBRANE Has own DNA Contains thylakoid sacs with chlorophyll for photosynthesis http://stallion.abac.peachnet.edu/sm/kmccrae/BIOL2050/Ch1-13/JpegArt1-13/04jpeg/04-28_chloroplasts_1.jpg http://media.pearsoncmg.com/bc/bc_campbell_essentials_2/cipl/04/HTML/source/04-17-chloroplast-nl.htm

FLAGELLA & CILIA Made of microtubules 9 + 2 arrangement http://www.stchs.org/science/courses/sbioa/metenergy/flagella.jpg http://www.geocities.com/CollegePark/Lab/4551/fig12b.jpg FLAGELLA & CILIA Made of microtubules 9 + 2 arrangement Move substances past cells Help move cells http://web.jjay.cuny.edu/~acarpi/NSC/13-cells.htm http://www.sk.lung.ca/content.cfm?edit_realword=hwbreathe

FLAGELLA WHAT’S THE DIFFERENCE? CILIA Many short Few Long Animation from: http://web.jjay.cuny.edu/~acarpi/NSC/13-cells.htm Few Long

WHAT’S SPECIAL ABOUT PLANT CELLS? Cell wall HUGE vacuoles Chloroplasts No centrioles

CELL WALL Outside cell membrane Supports and protects cell http://www.windows.ucar.edu/kids_space/images/brick_wall.jpg CELL WALL Outside cell membrane Supports and protects cell Plants- Cellulose makes it “sturdy” Bacteria- have peptidoglycan instead http://web.jjay.cuny.edu/~acarpi/NSC/13-cells.htm

VACUOLES Huge in plants Storage space for water, food, enzymes, waste Image from: http://www.biologycorner.com/resources/plant_cell.gif

VACUOLES can store WATER http://www.biology4kids.com/files/cell_vacuole.html

Freshwater organisms have contractile vacuoles to control excess water in cells (HOMEOSTASIS) http://www.microscopy-uk.org.uk/mag/imgjun99/vidjun1.gif

WHAT’S DIFFERENT ABOUT BACTERIAL CELLS? Cell wall NO NUCLEAR MEMBRANE DNA is circular No membrane bound organelles http://www.eurekascience.com/ICanDoThat/bacteria_cells.htm

WHICH IS BIGGER? _________ > _____________ > ___________ Plant cell Animal cell bacteria _________ > _____________ > ___________

DIFFERENCES IN ANIMAL CELLS, PLANT CELLS, AND BACTERIA ANIMAL CELL Eukaryotes Prokaryotes Cell membrane Nuclear membrane NO nuclear membrane NO cell wall Cell wall made of CELLULOSE Cell wall made of PEPTIDOGLYCAN Has ribosomes DNA in multiple chromosomes DNA in multiple chromosomes DNA is a single circular ring CYTOSKELETON Small vacuoles Really big vacuole NO vacuoles Has lysosomes Few lysosomes NO lysosomes Has centrioles NO centrioles NO chloroplasts Chloroplasts SMALLER size SMALL size SMALLEST size