Ce ls: Prokaryote vs
Eukaryote
Ce ls have evolved two
di ferent architectures:
Prokaryot e “styl e”
Eukaryot e “st yl e”
Prokaryote ce ls are smaler
and simpler
Commonly known as bact eria
10-100 microns insize
Singl e-cel l ed(unicel l ul ar ) or
Filament ous (st r ings of singl e
cel l s)
These ar e
pr okar yot e
E. col ibact eria
on t he head of a
st eel pin.
Prokaryote ce ls are simply built
(example: E. coli)
capsul e: sl imy out er
coat ing
cel l wal l : t ougher
middl e l ayer
cel l membr ane: del icat e
inner skin
Prokaryote ce ls are simply built
(example: E. coli)
cyt opl asm: inner l iquid fil l ing
DNA inone big l oop
pil l i: for st icking t o t hings
fl agel l a: for swimming
r ibosomes: for buil ding
prot eins
Prokaryote lifestyle
unicel l ul ar : al l
al one
col ony: for ms a
fil m
filament ous:
for ms a chain of
cel l s
Prokaryote Feeding
Phot osynt het ic: energy fr omsunl ight
Disease-causing: feed on l iving t hings
Decomposer s: feed on dead t hings
Eukaryotes are bigger and more
complicated
Have or ganel l es
Have chromosomes
can be mul t icel l ul ar
incl ude animal and pl ant cel l s
Organe les are membranebound ce l parts
Mini “or gans” t hat have
unique st r uct ur es and
funct ions
Locat ed incyt opl asm
Ce l Structures
Cell membr ane
del icat e l ipid
and prot ein
skin ar ound
cyt opl asm
found inal l
cel l s
Nucl eus
a membr ane-bound
sac evol ved t o
st or e t he cel l ’s
chr omosomes(DNA)
has pores: hol es
Nucl eol us
inside nucl eus
l ocat ion of
r ibosome
fact ory
made or RNA
mit ochondr ion
makes t he
cel l ’s energy
t he mor e
energy t he
cel l needs, t he
mor e
mit ochondr ia
it has
Ribosomes
buil d prot eins
fr omamino acids in
cyt opl asm
may be fr eefl oat ing, or
may be at t ached
t o ER
made of RNA
Endopl asmic
r et icul um
may be smoot h:
buil ds l ipids and
car bohydr at es
may be rough:
st or es prot eins
made by
at t ached
r ibosomes
Gol gi Compl ex
t akes insacs
of r aw
mat erial fr om
ER
sends out
sacs
cont aining
finished cel l
product s
Lysosomes
sacs fill ed wit h
digest iveenzymes
digest wor n out
cel l part s
digest food
absor bed by cel l
Cent r iol es
pair of bundl ed
t ubes
or ganize cel l
division
Cytoskeleton
made of
micr ot ubul es
found t hroughout
cyt opl asm
gives shape t o cel l
&moves or ganel l es
ar ound inside.
Structures found in plant ce ls
Cell wal l
very st r ong
made of
cel l ul ose
prot ect s cel l
fr omr upt uring
gl ued t o ot her
cel l s next door
Vacuol e
huge wat erfill ed sac
keeps cel l
pr essur ized
st or es
st ar ch
Chl or opl ast s
fill ed wit h
chl or ophyl l
t urn sol ar
energy into
food energy
How ar e pl ant and animal cel l s different ?
St r uct ure
cel l membr ane
nucl eus
nucl eol us
r ibosomes
ER
Gol gi
cent r iol es
cel l wal l
mit ochondria
chol or pl ast s
Onebig vacuol e
cyt oskel et on
Animal cel l s
Yes
Yes
yes
yes
yes
yes
yes
no
yes
no
no
yes
Pl ant cel l s
yes
yes
yes
yes
yes
yes
no
yes
yes
yes
yes
Yes
Eukaryote ce ls can be
multice lular
The whol e cel l can be special ized for
one job
cel l s can wor k t oget her as t issues
Tissues can wor k t oget her as or gans
Advantages of each kind of ce l
architecture
Pr okar yot es
Eukaryot es
simpl e and easy t o gr ow
can special ize
fast r eproduct ion
mul t icel l ul ar ity
al l t he s ame
can buil d l ar ge bodies
Examples of specialized euk.
ce ls
l iver cel l :
special ized t o
det oxify bl ood
and st or e
gl ucose as
glycogen.
sper mcel l :
special ized t o
del iver DNA t o
egg cel l
Mesophyl l
cel l
special ize
d to
capt ure
as much
l ight as
possibl e
inside a
l eaf
How do animal ce ls move?
Some can cr awl wit h pseudopods
Some can swimwit h a fl agel l um
Some can swimvery fast wit h cil ia
Pseudopods
means “fakefeet ”
ext ensions of
cel l membr ane
exampl e: ameoba
Flagelum/flagela
l ar ge whipl iket ail
pushes or pul l s
cel l t hrough
wat er
can be singl e, or a
pair
Cilia
fine, hairl ike
ext ensions
at t ached t o cel l
membr ane
beat inunison
How did organeles evolve?
many scient ist s t heor ize
t hat eukar yot es evol ved
fr omprokaryot e
ancest or s.
in1981, Lynn Mar gul is
popul ar ized t he
“endosymbiont t heory.”
Endosymbiont theory:
a prokaryot e ancest or
“eats” a smal l er
prokaryot e
t he smal l er prokaryot e
evol ves a way t o avoid
being digest ed, and l ives
inside its new “host ”cel l
kind of l ikea pet .
Endo = inside
Symbiont = friend
t he smal l prokaryot es t hat can do
phot osynt hesis evol ve into chl or opl ast s,
and “pay”t heir host wit h gl ucose.
The smal l er prokaryot es t hat can do
aerobic r espir at ion evol ve int o
mit ochondr ia, and convert t he gl ucose
into energy t he cel l can use.
Bot h t he host and t he symbiont benefit
fr omt he r el at ionship
Chl or el l a ar e
t iny gr eencel l s
t hat l iveinside
some amoeba...
endosymbiosis
may st ill be
evol ving t oday!