Transcript Lecture #3 Date

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 MEMBRANE
(also called plasma membrane)
SEE HOW
MEMBRANES FORM
PHOSPHOLIPID BILAYER with PROTEINS
Hydrophobic tails face in
Hydrophilic heads face out
Outside
of cell
Carbohydrate
chains
Proteins
Cell
membrane
Inside
of cell
(cytoplasm)
Protein
channel
Lipid bilayer
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
http://vilenski.org/science/safari/cellstructure/cellmembrane.html
• 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://www.d.umn.edu/~sdowning/Membranes/membraneImages/jpegimages/diffusionmedium.jpg
CYTOPLASM
Image from: http://faculty.stcc.cc.tn.us/jiwilliams/labprojectsmenu.htm
(Between nucleus and cell membrane)
Includes
ORGANELLESsmall structures with
a specific function
CYTOSOL-semi-fluid “goo”
Image from: http://vilenski.org/science/safari/cellstructure/cytoplasm.html
NUCLEUS
Image from: http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookCELL2.html
• Surrounded by DOUBLE membrane
(Nuclear envelope)
•Nuclear pores-
allow molecules in & out
•Contains DNA
•Control center
Replication
(DNA → DNA)
Transcription
(DNA → RNA)
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
CHROMATINspread out in NON-dividing cells to access info
CHROMOSOMEScondensed 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)
http://vilenski.org/science/safari/cellstructure/golgi.h
“UPS” of cell
Modify, sort, & package molecules from ER
for storage OR transport out of cell
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:
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
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
WHAT’S THE DIFFERENCE?
CILIA
•
•
Many
short
Animation from: http://web.jjay.cuny.edu/~acarpi/NSC/13-cells.htm
FLAGELLA
•Few
•Long
WHAT’S SPECIAL ABOUT PLANT CELLS?
• Cell wall
• HUGE vacuoles
• Chloroplasts
• No centrioles
http://www.windows.ucar.edu/kids_space/images/brick_wall.jpg
CELL WALL
Outside cell membrane
Supports and protects cell
PlantsCellulose 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
http://www.eurekascience.com/ICanDoThat/bacteria_cells.htm
• No membrane
bound organelles
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 cell wall
Cell wall made of
CELLULOSE
Cell wall made of
PEPTIDOGLYCAN
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
NO nuclear membrane