The Mixed-Up Cells

DISCOVERY LAB 2000
Series #4: The Mixed-Up Cells

Click on the arrows in the side scroll bar to move up and down the page.

"Welcome to Discovery Lab 2000."
Professor Mill Ennium has left the
Discovery Lab in the hands his trusty
lab assistants. As one of his assistants, you find
yourself exploring the lab for the first
time on your own.

You'll need to have your science journal
handy to record data throughout the lesson.


Across the room you spy a box of microscope slides labeled "Cells." Curiously you wander over for a closer look.		Upon opening the box you discover that there are two groups of slides-- "Plant Cells" and "Animal Cells."

As you turn to place the first slide on the stage of the microscope, the slides tumble out onto the counter.
	"Boy, do I have a problem now!" you utter in a panic. How will I ever sort these slides back into their original groups?"

What is your plan of action for solving this problem?

Type in your ideas by placing the arrow in the box.
Click on the mouse to get the cursor. When you are finished
typing your ideas, click on the "Done" button.

Just as you begin to sort the slides, IN00341_.WMF (16316 bytes)
you hear the door knob turn.
The professor is back already!
In a rush, you shove the slides back
into the box and conceal it
under the lab table.

You don't want him to find the lab in a mess!

After all, this is the first time

he's left it in your hands.

"So, what were you working on while I was away?"
the professor asked.

Quickly you reply,
"Oh..., I was just gathering information about cells
and wondering
how you tell the difference between plant and animal cells."

Just as you hoped, the professor fell right into
a brief lecture on cells!
Click on the blue portion of the sentence to preview the lecture.

After the lecture, Prof. E. asks questions to see what you have learned.

Question #1:
Which of the following living organisms is made up of cells?

Click the arrow to choose an answer.

Question #2:
Why are cells important to the life of living organisms?

Click in the box below and type your answer.

Hey, that wasn't so bad! But, I still have to sort the slides back into their two original groups so I'd better get a move on. Now, let's see if I can get the professor's help without him knowing it."

"How crafty I am! He's helping me solve my problem and doesn't even know it!"
"Okay, Professor, now I have a few questions of my own! Let's suppose I'm viewing a cell slide using the microscope. How would I know whether it is a plant or an animal cell?"

"Well, you see it's like this. A cell is like a house, and inside the cell there are different rooms. These rooms are called organelles.

Each organelle has a special purpose of its own.

Scientists have discovered differences between plant and animal cell organelles. That's how they tell these cells apart."

( This word sounds like "organ - L.")

"You lost me! I understood the house analogy,
but that word looks too big for me to understand."

"Well, it's actually quite simple. Look for a smaller word inside this big word that you do understand."

Type the smaller word in the box above.
Click "Check Me!" when you finish.

According to Professor E. organelles are essential parts of a cell just as organs are essential parts of your body. So, let's take a closer look into plant and animal cell organelles.

At this time, you should make a note in your science journal about the meaning of the term organelle.

Animal cells are really cool to examine under the microscope! The organelles are fun to explore!

"Let's begin by taking a closer look at the animal cell," the professor suggests.

"Let's take a closer look at the animal cell." Notice that the cell below is divided into colored sections. Each section represents a different part, or room, of the cell. Remember earlier we learned that a cell is like a house. A house is made up of several rooms.

What term was used to name the rooms inside a cell?

Now, let's discover why animal cell organelles are so important to the life of this organism. Click on the colored sections to learn the name and function of each organelle.

Click to learn more about this organelle.

Notice the yellow portion of the cell. This area is known as the cytoplasm. The cytoplasm is everything in the cell that is not an organelle. It surrounds the nucleus and holds everything else in the cell.

At this point, you should record your observations of the animal cell in your science journal.

Note Taking Tip:
Draw an animal cell and identify each organelle.

Now that you have been introduced to the organelles of an animal cell, let's see how much you remember.
Test your knowledge of animal cell organelles.
Click on the arrow and select the correct organelle.

Organelles of the Animal Cell

"Wow! The study of cells is really interesting!"

"Hey, I think I’m getting the hang of this animal cell stuff. I might just be able to separate these mixed up cells after all. But, I still need information on plant cells, so I’d better tune in to what the professor is discussing now. Are you ready to ‘dig’ into plant cells? Let’s go for it!"

"Cells contain organelles. Plant and animal cells contain some of the same ones."

"Well now, my trusty lab assistant, it appears that you have your facts straight about the animal cell organelles. Good for you! Now let's move on and take a closer look into the plant cell,"
suggested the professor. "Now for a closer look into the plant cell."

"Okay, think
about the organelles of the animal cell. The plant cell is made of those same organelles plus these two:
cell wall
and
chloroplast."

"Imagine that! There are only two additional organelles in the plant cell."

Trivia Question!

"What do you get when you add chloroplast and a cell wall to the animal cell organelles?
Click in the box and type your answer.

"Take a look at the diagram of the plant cell below. Notice the purple outline around the cell. This is the cell wall. Click on the cell wall to learn the functions of this organelle."

"The yellow portion of the cell is called the cytoplasm. It is the jelly-like material that surrounds the nucleus and holds everything else in the cell."

"Excellent! Now take a look at the portions of the cell that are green. These organelles are called chloroplasts."
Click on one of the chloroplast in the cell model above to learn about its function.

This would be a good time to click on the organelles of the plant cell above and review. Record your observations in your science journal.

Note Taking Tip:
Draw a plant cell and identify each organelle.

Remember...

Animal and plant cells share the same organelles except the two we just discovered.

At this point, the professor suggested, "Check your understanding of the plant cell while I exit the lab to take care of some business."

Click on the arrow in each box and select the name for the organelle.

"Observe the organelles of the plant cell and I will return in a few minutes," the professor suggested.

Organelles of a Plant Cell

	"This is probably a great time for you to collect your thoughts about the information presented up to this point. Organize your data by describing the similarities and differences you've observed about animal and plant cells."
	Click inside the white box below and type the similarities and differences you've observed. Click the "Done" button when you finish.

In your science journal, explain the differences between plant and animal cell structures.

"Okay, animal cells, plant cells, animal, plant,..."

"While Professor E. is still out of the lab, I better begin sorting the cell slides back into their two original groups. So, I'll take the information the professor gave and apply it. With any luck at all, this mess will be straightened up before he returns.

"Remember the problem?
Klutzy me dropped the box that contained the cell slides. Now, the slides are all mixed up!"

"Can you believe it? The first time he leaves Lab 2000 completely in my hands, I manage to make such a mess!"

"Think about how you would sort the slides. What would be your first step?"

Click on the arrow below and select your answer.

How much longer before the professor returns? "I've been doing some planning of my own.
On the next page, take a look at two of my ideas and decide which one I should use. Keep in mind that I don't have much time. The professor will be back any minute!"

Solution # 1 HH00522_.WMF (2946 bytes)

Solution # 2 HH00522_.WMF (2946 bytes)

Step 1 Closely examine each slide under the microscope and identify the organelles within the cell.

Step 2 Locate the two organelles that are only found in plant cells (chloroplasts, cell wall).

Step 3 If chloroplasts and a cell wall exist, place that slide in the plant cell category.

Step 4 If a cell wall and chloroplasts are not present, place that slide in the animal cell group.

Step 5 Follow this procedure for each slide.

Which solution is better?

Step 1 View the slides individually under the microscope. Locate the nucleus.

Step 2 Next, identify the vacuole because all cells, plant and animal, contain this organelle.

Step 3 Locate the cell membrane.

Step 4 Locate the mitochondria.

Step 5 Then, locate the cell wall.

Step 6 If a cell wall is present, look for chloroplasts.

Step 7 If a cell wall and chloroplasts are present, the slide belongs in the plant cell category.

Step 8 If you are unable to locate a cell wall and chloroplasts, place this slide in the animal cell category.

Step 9 Follow this procedure until every slide is returned to its original category.

"What makes one solution better than the other?"

Explain why one solution is better than the other. Record your explanation in your science journal.

Examine the cell slides below. Follow the steps given in the better solution to separate the plant and animal cell slides.

Slide A

Slide B

Slide C

Slide D

Which slides show examples of plant cells?
Click on the arrow and make a selection.

Which slides show examples of animal cells?
Click on the arrow and make a selection.

"Congratulations! Together, you and I have created a solution for sorting these mixed up slides!"

"We easily grouped these two slides of plant cells because they each contain a cell wall and chloroplasts."

Slide B

Slide D

"We know that these slides belong in the animal cell category because no cell wall or chloroplasts are present."

Slide A

"Well, I do believe I can sort these slides back into their original groups. I just need to remember these basic facts about plant and animal cells:"

All living organisms, plant and animal, are made of cells.
Cells are visible only with the use of a microscope.
Each cell is like a house that contains different rooms called organelles.
The organelles within a cell have special functions or jobs.
All cells contain certain organelles, but only plant cells have a cell wall and chloroplast.

"How could such an innocent looking person such as myself ever cause a problem? Oh, no, not again......"

"Thanks for your help in the case of
The Mixed-Up Cells.
I better run! Oops! You would think I'd learn to move around the lab more carefully. After all, it was my 'klutziness' that got me into this mess in the first place!"