Upload
beverly-hodges
View
217
Download
3
Tags:
Embed Size (px)
Citation preview
Eukaryotes
Cognitive Learning Systems, Inc © 2009
Cognitive Learning Systems, Inc © 2009
EukaryotesUnderstanding Eukaryotic CELLs
Organisms
Cognitive Learning Systems, Inc © 2009
Imag
es c
ourt
esy:
htt
p://
imae
s.fw
s.go
v ;h
ttp:
//w
ww
/gle
rl.no
aa.g
ov;
US
DA
-NR
CS
PLA
NT
S D
atab
ase
/ H
erm
an,
D.E
., e
t al
. 19
96.
Nor
th
Dak
ota
tree
han
dboo
k. U
SD
A N
RC
S N
D S
tate
Soi
l Con
serv
atio
n C
omm
ittee
; N
DS
U E
xten
sion
and
Wes
tern
Are
a P
ower
Adm
inis
trat
ion,
B
ism
arck
; w
ww
. M
br-p
wr.
usgs
.gov
; af
sc.n
oaa.
gov;
htt
p://
phil.
cdc.
gov;
ww
w.n
asa.
gov
;and
Nat
iona
l Agr
icul
tura
l Lib
rary
, A
gric
ultu
ral
Res
earc
h S
ervi
ce,
U.
S.
Dep
artm
ent
of A
gric
ultu
re."
Organisms
Cognitive Learning Systems, Inc © 2009
Images courtesy: http://imaes.fws.gov ;http://www/glerl.noaa.gov; USDA-NRCS PLANTS Database / Herman, D.E., et al. 1996. North Dakota tree handbook. USDA NRCS ND State Soil Conservation Committee; NDSU Extension and Western Area Power Administration, Bismarck; www. Mbr-pwr.usgs.gov; afsc.noaa.gov; http://phil.cdc.gov; www.nasa.gov ;and National Agricultural Library, Agricultural Research Service, U. S. Department of Agriculture.”
All of these organisms are made up of cells.
Some are made of only a single cell.(unicellular organisms)
Some are a collection or colony of single cells.
Some are made up of many cells.(multicellular organisms)
The cells that make up these organisms are EUKARYOTIC cells.
Eukaryotes
You observed eukaryotic cells from plant and animal samples in the CELL Microscopic Explorations. Here are two examples of specimens you observed.
Cognitive Learning Systems, Inc © 2009
Do these two eukaryotic cells look the same?
Do you think all eukaryotic cells look the same?
Eukaryotes
Cognitive Learning Systems, Inc © 2009
What are some characteristics that are found in both of the eukaryotic cells above?
Do you think there are characteristics that all eukaryotic cells have in common?
Eukaryotic Cells
Cell Membrane
CytoplasmNucleus
A eukaryotic cell can be defined as a cell that has a cell membrane AND other structures called organelles.
The CELL MEMBRANE is the structure that surrounds the cell.
The CYTOPLASM is the jelly-like substance inside the cell membrane.
One of the organelles in a eukaryotic cell is the NUCLEUS.
Cognitive Learning Systems, Inc © 2009
Plastic Bag(cell membrane)
Tea Bag(nucleus)
Jelly(cytoplasm)
Model of a Eukaryotic Cell
Cognitive Learning Systems, Inc © 2009
Eukaryotic CellsOne way to understand eukaryotic cells is to think of them as having two separate compartments, one inside the other. All eukaryotic cells can be divided this way.
Outside the nucleus
Inside the nucleus
Eukaryotic cells have different structures inside the nucleus and outside the nucleus.
Because they have different structures inside and outside the nucleus, there are different functions that the cell performs inside and outside the nucleus.
Cognitive Learning Systems, Inc © 2009
Cognitive Learning Systems, Inc © 2009
Plastic Bag(cell membrane)
Tea Bag(nucleus)
Jelly(cytoplasm)
Model of a Eukaryotic Cell
Check Understanding
Inside the Nucleus
Cognitive Learning Systems, Inc © 2009
The nucleus is surrounded by a membrane. This membrane is called the NUCLEAR MEMBRANE.
nuclear membrane
The Nucleus and Inside the Nucleus
Cognitive Learning Systems, Inc © 2009
There are several structures within the nucleus.
One of the most important structures is DNA.
DNA is a substance that contains all of the information or instructions necessary for the cell to survive and multiply.
DNA
Inside the Nucleus
Cognitive Learning Systems, Inc © 2009
The nucleus controls cell division.
There are times when new cells need to be made. New cells are made by copying all of the substances in a cell and then splitting or dividing the cell into two.
At the end of the process there are two cells that were made from one original cell.
Inside the Nucleus
Cognitive Learning Systems, Inc © 2009
The DNA inside the nucleus looks different depending upon what function occurs in the nucleus.
When the cell is NOT dividing (splitting) the DNA looks like a mass of tangled thread.
Inside the NucleusWhen the cell IS DIVIDING (splitting) the DNA is organized into structures called CHROMOSOMES.
Cognitive Learning Systems, Inc © 2009
chromosomes
Outside the Nucleus
Cognitive Learning Systems, Inc © 2009
OUTSIDE the nucleus of the cell are other structures known as ORGANELLES.
Examples of some of these organelles are:
Endoplasmic reticulumMitochondriaLysosomeperoxisome
Cognitive Learning Systems, Inc © 2009
Tissue Paper(organelles)
Plastic Bag(cell membrane)
Tea Bag(nucleus)
Jelly(cytoplasm)
Model of a Eukaryotic Cell
Outside the Nucleus
Cognitive Learning Systems, Inc © 2009
The organelles outside the nucleus are responsible for carrying out the instructions that were contained within the DNA.
They perform many different types of functions.
Some of these functions include:
Making energy for the cell
Making other substances needed by the cell such as fats and sugars.
Breaking down harmful substances inside the cell.
Check Understanding
Cognitive Learning Systems, Inc © 2009
1. Describe how the area of a eukaryotic cell that is inside the nucleus is different from the area outside the nucleus. How is it similar?
2. Why does DNA not come in contact with organelles outside the nucleus?
Cognitive Learning Systems, Inc © 2009
EukaryotesMulticellular and Unicellular Organisms
What Can You Recall?
Cognitive Learning Systems, Inc © 2009
1. Your friend is looking at eukaryotic cells from three different organisms. Name two structures she is likely to see in ALL three specimens.
2. Your friend states that the DNA in a cell looks the same all of the time. Is he right or wrong? Why?
Unicellular Organisms
Protists are a group of eukaryotic organisms. SOME protists are unicellular (consist of a SINGLE CELL).
Examples of protists that are unicellular are amoebas, euglenas (a type of algae), and paramecia.
Look at the shape of each of these unicellular eukaryotes.
Is the shape the same?
Are all of the PARTS of the eukaryotic cells the same?
Images courtesy: http://rst.gsfc.nasa.gov;www.glerl.noaa.gov;
Cognitive Learning Systems, Inc © 2009
Unicellular Organisms- Protists
Cognitive Learning Systems, Inc © 2009
An amoeba is a SINGLE EUKARYOTIC CELL. It is a unicellular organism.
Parts of its cell membrane can extend outward. These are called pseudopodia.
Pseudopodia help the amoeba MOVE and ENGULF food.
pseudopodium
pseudopodium
Ima
ge
cou
rte
sy:
htt
p://
rst.
gsf
c.n
asa
.go
v
Unicellular Organisms- Protists
Cognitive Learning Systems, Inc © 2009
EUGLENA is a SINGLE EUKARYOTIC CELL. It is an unicellular organism.
One of it’s unique characteristics is that it has a small “tail” called a FLAGELLUM at one end.
The FLAGELLUM helps the euglena move.
flagellum
Image courtesy: http://www.glerl.noaa.gov
Unicellular Organisms-Protists
Cognitive Learning Systems, Inc © 2009
A paramecium is an SINGLE EUKARYOTIC CELL. It is a unicellular organism.
It has tiny hairs that extend from all around its cell membrane. These hairs are called CILIA.
CILIA can move. The movement of the cilia helps the paramecium to move.
cilia
Ima
ge
cou
rte
sy:
htt
p://
rst.
gsf
c.n
asa
.go
v
Unicellular Organisms- Fungi
Cognitive Learning Systems, Inc © 2009
Fungi are another group that have SOME unicellular organisms.
Yeast are fungi that are unicellular eukaryotic cells.
Yeast do not have a flagellum or cilia.
How does the shape of yeast compare to that of the amoeba, paramecium and euglena?
Ima
ge
cou
rte
sy:
ww
w.n
asa
.go
v p
ho
to b
y V
ikto
r S
tolc
an
d S
igri
d R
ein
sch
."
Cognitive Learning Systems, Inc © 2009
Tissue Paper(organelles)
Plastic Bag(cell membrane)
Tea Bag(nucleus)
Jelly(cytoplasm)
Model of an Amoeba
PSEUDOPODIUM
PSEUDOPODIUM
PSEUDOPODIUM
Cognitive Learning Systems, Inc © 2009
Tissue Paper(organelles)
Plastic Bag(cell membrane)
Tea Bag(nucleus)
Jelly(cytoplasm)
Model of a Euglena
FLAGELLUM(string)
Cognitive Learning Systems, Inc © 2009
Tissue Paper(organelles)
Plastic Bag(cell membrane)
Tea Bag(nucleus)
Jelly(cytoplasm)
Model of a Paramecium
CILIA(string)
CILIA(string)
Multicellular Organisms
Cognitive Learning Systems, Inc © 2009
Multicellular organisms are organisms made up of MANY EUKARYOTIC cells.
There are different types of multicellular organisms. Two types of multicellular organisms are plants and animals.
ALL plant and animals are multicellular organisms.
Plants
Animals
Imag
es c
ourt
esy:
US
DA
-NR
CS
PLA
NT
S D
atab
ase
/ H
erm
an,
D.E
., e
t al
. 19
96.
Nor
th D
akot
a tr
ee h
andb
ook.
US
DA
NR
CS
ND
S
tate
Soi
l Con
serv
atio
n C
omm
ittee
; N
DS
U E
xten
sion
and
Wes
tern
Are
a P
ower
Adm
inis
trat
ion,
Bis
mar
ck;w
ww
. M
br-
pwr.
usgs
.gov
; R
ober
t H
. M
ohle
nbro
ck @
US
DA
-NR
CS
PLA
NT
S D
atab
ase
/ U
SD
A S
CS
. 19
89.
Mid
wes
t w
etla
nd f
lora
: F
ield
of
fice
illus
trat
ed g
uide
to
plan
t sp
ecie
s. M
idw
est
Nat
iona
l Tec
hnic
al C
ente
r, L
inco
ln;
http
://im
ages
.fw
s.go
v; S
cott
Som
ersh
oe,
US
GS
Pat
uxen
t W
ildlif
e R
esea
rch
Cen
ter”
; w
ww
.fw
s.go
v; a
nd w
ww
.mag
azin
e.no
aa.g
ov
Multicellular Organisms
Cognitive Learning Systems, Inc © 2009
SOME protists and fungi are MULTICELLULAR.
Mushrooms and mold are multicellular. These organisms are examples of fungi.
Green algae and kelp are multicellular. These organisms are examples of protists.
Fungi
Protists
Imag
es c
ourt
esy:
"N
atio
nal A
gric
ultu
ral L
ibra
ry,
Agr
icul
tura
l Res
earc
h S
ervi
ce,
U.
S.
Dep
artm
ent
of A
gric
ultu
re."
; w
ww
.epa
.gov
; w
ww
.oly
picc
oast
.noa
a.go
v; a
nd s
wr.
nmfs
.noa
a.go
v
Multicellular Organisms
Cognitive Learning Systems, Inc © 2009
Just like the eukaryotic cells of unicellular organisms, the shapes of eukaryotic cells in multicellular organisms are NOT always the same.
There are also SOME structures that are different in different types of organisms.
For example, plants have two structures not found in animal cells:
CELL WALLCHLOROPLASTS
chloroplast
cell wall
cell membrane
chloroplast
chloroplast
nucleus
cytoplasm
Cognitive Learning Systems, Inc © 2009
Unicellular vs Multicellular Organisms
In UNICELLULAR ORGANISMS each cell accomplishes ALL of the functions necessary for the organism’s survival.
Ima
ge
s co
urt
esy
: h
ttp:
//w
ww
/gle
rl.n
oa
a.g
ov;
an
d w
ww
.fws.
gov
In MULTICELLULAR ORGANISMS different cells can perform different functions.
BUT the cells are ORGANIZED in a special way to perform ALL of the functions needed for survival.
Hierarchical OrganizationMulticellular organisms have developed a system of organizing cells in order to best accomplish functions necessary to sustain life.
Cognitive Learning Systems, Inc © 2009
In many multicellular organisms, cells are organized into larger structures called tissues. (Example: Heart cells are organized into muscle tissue.)
Tissues are organized into larger structures. In some organisms like animals these structures are called organs.(Example: Muscle tissue and other tissues are organized to form the heart.)
Organs in animals (other structures in other organisms) are organized into systems.(Example: the circulatory system)
Systems work together for overall function of an organism.(Example: human)
cell
tissue
organ
system
organism
Check Understanding
Cognitive Learning Systems, Inc © 2009
1. Describe how eukaryotic unicellular organisms differ from multicellular organisms. Describe how they are similar.
2. Give two examples of structures that may NOT be found in all eukaryotic cells.
Cognitive Learning Systems, Inc © 2009
EukaryotesMaking and Applying Connections
Making and Applying Connections
1. Which of these are you most likely to find in all eukaryotic cells?
A. FlagellumB. PseudopodiaC. ChloroplastsD. Cytoplasm
Cognitive Learning Systems, Inc © 2009
Inside the Nucleus
Cognitive Learning Systems, Inc © 2009
2. Charles looks at a eukaryotic cell using a microscope. The cell he sees is below. The arrow points to structures he observes in the nucleus. From the structures in the nucleus, Charles can conclude that that
A. the cell is movingB. the cell is dividingC. the cell is eatingD. the cell is resting
Making and Applying Connections
3. Which of the specimens has cells with both a flagellum and chloroplasts?
A. Elodea leafB. Human white blood cellsC. EuglenaD. Paramecium
Cognitive Learning Systems, Inc © 2009
Making and Applying Connections
4. Which of the above contain eukaryotic cells?
A. 1 and 2 onlyB. 1 and 3 onlyC. 1, 2 and 3 onlyD. 1, 2, 3 and 4
1. fungi 2. protist 3. plant 4. animal
Imag
es c
ourt
esy:
htt
p://
ww
w/g
lerl.
noaa
.gov
; "
Nat
iona
l Agr
icul
tura
l Lib
rary
, A
gric
ultu
ral R
esea
rch
Ser
vice
, U
. S
. D
epar
tmen
t of
Agr
icul
ture
.”;
ww
w.f
ws.
gov;
and
Mbr
-pw
r.us
gs.g
ov
Cognitive Learning Systems, Inc © 2009
Cognitive Learning Systems, Inc © 2009
5. Jill is studying the organelles in the area of the cell shaded red. All of these organelles are
Making and Applying Connections
A. Inside the nucleus and inside the cell membraneB. Outside the nucleus and outside the cytoplasmC. Outside the cytoplasm and inside the cell membraneD. Inside the cell membrane and outside the nucleus
Cognitive Learning Systems, Inc © 2009
6. Henry wants to test whether amoebas can survive feeding only on algae or only on bacteria. He places two amoebas in matching containers of water. What should he do next?
Making and Applying Connections
A. Add algae to both containersB. Add bacteria to both containersC. Add bacteria to one container and algae to the other containerD. Add bacteria and algae to both containers
Cognitive Learning Systems, Inc © 2009
7. The diagram below shows a eukaryotic cell that will soon divide. After the process of the cell division is completed, how many cells will there be?
A. 1B. 2C. 3D. 4
Making and Applying Connections
Cognitive Learning Systems, Inc © 2009
8. The functions that occur outside the nucleus and inside the nucleus are different because
A. The cell membrane surrounds only the organelles outside the nucleus.B. The structures inside and outside the nucleus are different.C. The cytoplasm comes in contact with both the nucleus and the organelles outside the nucleus.D. The structures inside and outside the nucleus are the same.
Making and Applying Connections
Cognitive Learning Systems, Inc © 2009
Tissue Paper(organelles)
Plastic Bag(cell membrane)
Tea Bag(nucleus)
Jelly(cytoplasm)
9. The diagram above shows a model of a eukaryotic cell. Which answer best explains how the model would change if the nuclear membrane burst?
A. The grape jelly would leak out of the plastic bag.B. All of the tissue paper would leak out of the plastic bag.C. The tea in the tea bag would mix with the jelly.D. The fabric of the tea bag would leak out of the plastic bag.
Making and Applying Connections
Cognitive Learning Systems, Inc © 2009
10. Which of the following statements is true?
A. Eukaryotic cells in all unicellular organisms are the same shape.
B. Eukaryotic cells in multicellular organisms all perform the same function.
C. Eukaryotic cells in unicellular organisms are organized into tissues. D. Eukaryotic cells are found in unicellular and multicellular organisms.
Making and Applying Connections