Eukaryotes Cognitive Learning Systems, Inc © 2009.

Eukaryotes

Cognitive Learning Systems, Inc © 2009


EukaryotesUnderstanding Eukaryotic CELLs

Organisms


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


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.


Do these two eukaryotic cells look the same?

Do you think all eukaryotic cells look the same?

Eukaryotes


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.


Plastic Bag(cell membrane)

Tea Bag(nucleus)

Jelly(cytoplasm)

Model of a Eukaryotic Cell


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.




Tea Bag(nucleus)

Jelly(cytoplasm)


Check Understanding

Inside the Nucleus


The nucleus is surrounded by a membrane. This membrane is called the NUCLEAR MEMBRANE.

nuclear membrane

The Nucleus and Inside the Nucleus


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


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


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.


chromosomes

Outside the Nucleus


OUTSIDE the nucleus of the cell are other structures known as ORGANELLES.

Examples of some of these organelles are:

Endoplasmic reticulumMitochondriaLysosomeperoxisome


Tissue Paper(organelles)


Tea Bag(nucleus)

Jelly(cytoplasm)


Outside the Nucleus


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


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?


EukaryotesMulticellular and Unicellular Organisms

What Can You Recall?


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;


Unicellular Organisms- Protists


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


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


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


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

."




Tea Bag(nucleus)

Jelly(cytoplasm)

Model of an Amoeba

PSEUDOPODIUM

PSEUDOPODIUM

PSEUDOPODIUM




Tea Bag(nucleus)

Jelly(cytoplasm)

Model of a Euglena

FLAGELLUM(string)




Tea Bag(nucleus)

Jelly(cytoplasm)

Model of a Paramecium

CILIA(string)

CILIA(string)

Multicellular Organisms


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



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



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


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.


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


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.


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


Inside the Nucleus


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


3. Which of the specimens has cells with both a flagellum and chloroplasts?

A. Elodea leafB. Human white blood cellsC. EuglenaD. Paramecium



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



5. Jill is studying the organelles in the area of the cell shaded red. All of these organelles are


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


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?


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


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



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.





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.



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.


Eukaryotes Cognitive Learning Systems, Inc © 2009.

Documents

Transcript of Eukaryotes Cognitive Learning Systems, Inc © 2009.