Transcript AP ch6 cells - Foglia and Reidell

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
AP BIOLOGY Chapter 6
Cell Structure & Function
WHAT’S NEW you didn’t learn in 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
NUCLEAR ENVELOPE
http://cellbio.utmb.edu/cellbio/nuclear_envelope.htm
DOUBLE MEMBRANE is
fused in spots forming
NUCLEAR PORES
NUCLEAR LAMINA- netlike array of protein
filaments on nuclear side of envelope that
maintains the shape of the nucleus
(Play a role in reforming nuclear membrane after cell division,
if you inject antibodies to lamina proteins, nucleus can’t
reform after mitosis)
NUCLEAR ENVELOPE
Nucleus
Nucleus
1 µm
Nucleolus
Chromatin
Nuclear envelope:
Inner membrane
Outer membrane
Nuclear pore
Pore
complex
Rough ER
Surface of nuclear
envelope.
1 µm
Ribosome
0.25 µm
Close-up of
nuclear
envelope
Figure 6.10
Pore complexes (TEM).
Nuclear lamina (TEM).
ENDOMEMBRANE SYSTEM
Regulates protein traffic and performs
metabolic functions in the cell
Includes:
Plasma membrane
Nuclear membrane
Endoplasmic reticulum
Golgi apparatus
Vacuoles
Lysosomes
INSULIN being released by pancreas cells
using exocytosis
http://fig.cox.miami.edu/~cmallery/255/255ion/fig14x26.jpg
Golgi apparatus
Cisternae = Flattened membrane sacs
(look like stacked pancakes)
2 sides = 2 functions


cis = (receives vesicles by fusion)
trans = buds off vesicles to send to
other places (shipping face)
Animation from: http://www.franklincollege.edu/bioweb/A&Pfiles/week04.html
See a Golgi movie
EVERYTHING’S CONNNECTED!
LYSOSOMES
(common in animal cells but rare in plant cells)
Contain hydrolytic enzymes for intracellular
digestion
• Food (Phagocytosis)
See movie
• Damaged organelles
AUTOPHAGY
~ “eating self”
LYSOSOMES:
Uncontrolled release of lysosome contents into the
cytoplasm can also cause cell death (necrosis)
• APOPTOSIS (self-destruct mechanism)
“cell suicide”
Embryonic development
Removes damaged cells
Immune response
Cancer cells and AIDS virus override self-destruct
signals
WHITE BLOOD CELLS USE LYSOSOMES TO
DIGEST ENGULFED BACTERIA
(Phagocytosis)
http://fig.cox.miami.edu/~cmallery/255/255ion/fig14x28.jpg
ANIMAL VACUOLES & VESICLES
“transport vehicles”
• FOOD VACUOLES
Phagocytosis/ fuse with lysosomes
• CONTRACTILE VACUOLES
Freshwater organisms pump
out excess water
http://www.microscopy-uk.org.uk/mag/imgjun99/vidjun1.gif
PLANT VACUOLES (Central Vacuole)
Surrounded by membrane
= TONOPLAST
Selectively permeable
– controls what goes in & out
STORAGE
• Water
• Stockpile proteins/inorganic ions
• Deposit metabolic byproducts
• Store pigments
• Store defensive compounds against herbivores
Other cell parts with membranes that
are NOT part of the Endomembrane
system:
– Mitochondria
– Plastids
– Peroxisomes
MITOCHONDRIADOUBLE MEMBRANE
Outer membrane
Inner membrane (CRISTAE)
increases surface area for
chemical reactions
Intermembrane space=
Space between inner membrane
& outer membrane
MATRIX = Space inside cristae folds
contains DNA, enzymes, ribosomes
Chloroplasts – site for
photosynthesis in plants
•DOUBLE MEMBRANE
•Has own DNA
• Thylakoids – membrane sacs
containing light-capturing pigments
•Grana –
closed compartments of stacked
thylakoid membranes
•Stroma – fluid surrounding thylakoids
PLASTIDS
CHLOROPLASTS- contain pigment
chlorophyll for photosynthesis
CHROMOPLASTS- contain pigments
that give fruits and flowers colors
AMYLOPLASTS- store starch (amylose)
in roots and tubers (colorless)
http://www.jonathanwald.com/800x600/images/Red-Apple.jpg
http://en.wikipedia.org/wiki/Image:Potato_-_Amyloplasts.jpg
Who else has a circular chromosome not
found within a nucleus?
Endosymbiotic Theory
http://en.wikipedia.org/wiki/Lynn_Margulis
• Originally proposed in early 1900’s
• Idea reintroduced in 1963 by Lynn Margulis
• Suggests that engulfed prokaryotes shared
symbiotic relationship with host cell
• Advantages for both:
~ one supplies energy
~ other raw materials & protection
ENDOSYMBIOTIC THEORY
See a movie about
ENDOSYMBIOTIC THEORY
http://www.mun.ca/biology/scarr/Endosymbiosis_theory.gif
Evidence for Endosymbiotic theory
1. Mitochondria and chloroplasts have circular DNA like
bacteria.
2. Mitochondria and chloroplasts have ribosomes whose size
and structure resemble bacterial ribosomes.
3. Mitochondria and chloroplasts replicate independently of
cell division using binary fission like bacteria.
4. Inner membranes of mitochondria and chloroplasts have a
composition similar to bacterial membranes.
PEROXISOMES
Other digestive enzyme sacs
in both plants and animals
NOT part of endomembrane system
(proteins come from cytosol)
In fat storing seeds (called GLYOXYSOMES)
Break down fatty acids → sugars
transport to mitochondria for energy
In LIVER CELLS
Help detoxify alcohol & other poisons
PRODUCE HYDROGEN PEROXIDE (also a TOXIN)
but have enzyme (CATALASE) to break this down
H2O2 → H2O + O2