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

AP BIOLOGY Chapter 6What You Should Know Already

from BIO I

CELL MEMBRANE(also called plasma membrane)

PHOSPHOLIPID BILAYER with PROTEINSHydrophobic tails face inHydrophilic heads face out

Outsideof cell

Insideof cell(cytoplasm)

Cellmembrane

Proteins

Proteinchannel Lipid bilayer

Carbohydratechains

Membrane Image from: © Pearson Education Inc, Publishing as Pearson Prentice Hall; All rights reservedPhospholipid image from: http://bioweb.wku.edu/courses/BIOL115/Wyatt/Biochem/Lipid/P_lipid2.htm

SEE HOW MEMBRANES FORM

FLUID MOSAIC MODEL

Molecules in cell membranes are constantly moving and changing

Click here to See Fluidity

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)

Includes

ORGANELLES-small structures with a specific function

CYTOSOL-semi-fluid “goo”

Image from: http://vilenski.org/science/safari/cellstructure/cytoplasm.html

Image from: http://faculty.stcc.cc.tn.us/jiwilliams/labprojectsmenu.htm

NUCLEUS• Surrounded by DOUBLE membrane (Nuclear envelope)

•Nuclear pores- allow molecules in & out

•Contains DNA

•Control center Replication (DNA → DNA) Transcription (DNA → RNA)

Image from: http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookCELL2.html

NUCLEOLUS

• 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 productionImage from: http://www.agen.ufl.edu/~chyn/age2062/lect/lect_06/5_10B.GIF

Golgi apparatus (collection of Golgi bodies)

“UPS” of cellModify, sort, & package molecules from ER for storage OR transport out of cell

http://vilenski.org/science/safari/cellstructure/golgi.h

Image from: http://vilenski.org/science/safari/cellstructure/golgi.h

Image from: http://www.rsbs.anu.edu

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:

http://www.mgm.ufl.edu/images/bharfe/image3.jpghttp://research.yale.edu/ysm/images/78.3/articles-apoptosis-cells.jpg

“PROGRAMMED CELL DEATH” APOPTOSIS

Embryo developmentCell maintenance

Signal to self destructlost in cancer cells

CENTRIOLESMade of microtubulesAppear 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

• Contains thylakoid sacs with chlorophyll for

photosynthesis

http://www.seorf.ohiou.edu/~tstork/compass.rose/photosynthesis/chloro_sun_bathing.gif

http://stallion.abac.peachnet.edu/sm/kmccrae/BIOL2050/Ch1-13/JpegArt1-13/04jpeg/04-28_chloroplasts_1.jpghttp://media.pearsoncmg.com/bc/bc_campbell_essentials_2/cipl/04/HTML/source/04-17-chloroplast-nl.htm

http://www.stchs.org/science/courses/sbioa/metenergy/flagella.jpghttp://www.geocities.com/CollegePark/Lab/4551/fig12b.jpg

Move substances past cells

Help move cells

http://web.jjay.cuny.edu/~acarpi/NSC/13-cells.htmhttp://www.sk.lung.ca/content.cfm?edit_realword=hwbreathe

FLAGELLA & CILIAMade of microtubules9 + 2 arrangement

CILIA • Many• short

FLAGELLA•Few•Long

WHAT’S THE DIFFERENCE?

Animation from: http://web.jjay.cuny.edu/~acarpi/NSC/13-cells.htm

WHAT’S SPECIAL ABOUT PLANT CELLS?

• Cell wall

• HUGE vacuoles

• Chloroplasts

• No centrioles

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

http://www.windows.ucar.edu/kids_space/images/brick_wall.jpg

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 organelleshttp://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 PLANT CELL BACTERIA

Eukaryotes Eukaryotes Prokaryotes

Cell membrane Cell membrane Cell membrane

Nuclear membrane

Nuclear membrane

NO nuclear membrane

NO cell wall Cell wall made of

CELLULOSE

Cell wall made ofPEPTIDOGLYCAN

Has ribosomes Has ribosomes Has ribosomes

DNA in multiple chromosomes

DNA in multiple chromosomes

DNA is a single circular ring

CYTOSKELETON CYTOSKELETON CYTOSKELETON

Small vacuoles Really big vacuole

NO vacuoles

Has lysosomes Few lysosomes NO lysosomes

Has centrioles NO centrioles NO centrioles

NO chloroplasts Chloroplasts NO chloroplasts

SMALLER size SMALL size SMALLEST size