1. Protein Creation Pathway
Place your keyboard aside. Only use your mouse
click on the NUCLEUS to begin the tutorial

2. The Nucleus
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The nucleus (flashing circle) is nicknamed the “control center” of a cell. But why? The nucleus contains DNA in its active form and this DNA will ultimately be used as a blueprint to create proteins for use throughout the body. The process of creating a protein begins in the nucleus.
Click the arrow to zoom inside and view a nucleus.
See the dark spot inside the nucleus? This is the nucleolus. Give it a click.

3. The Nucleolus
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Nucleolus
The nucleolus is a dense region within the nucleus. This organelle (tiny cell part) is responsible for creating thousands of ribosomes. Ribosomes play an important role in the creation of proteins as we will see later.
Click the Nucleolus to see an artists drawing.
Nucleus

4. The Nucleolus
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The nucleolus is a dense region within the nucleus. This organelle (tiny cell part) is responsible for creating thousands of ribosomes. Ribosomes play an important role in the creation of proteins as we will see later.
Monosaccharides makes complex sugars
Fatty acids make lipids
Nucleotides make nucleic acids
These organelles are 3-dimensional. But they often look flat when viewed through a microscope. To proceed, answer the question below.
What are the monomers of a protein called?
monosaccharide
Fatty acid
Nucleotide
Amino acid

5. Ribosomes Correct! Amino acids make proteins.
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Correct! Amino acids make proteins.
By far, the ribosomes are the most numerous of all organelles. Remember, they are created by the nucleolus. After exiting the nucleus they themselves are responsible for the production of proteins within the cell. Because they are so small, they resemble tiny dots in this picture.
After they exit the nucleus, they are often attached to the endoplasmic reticulum (ER). Click HERE to see the ER and attached ribosomes.

6. Ribosomes
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By far, the ribosomes are the most numerous of all organelles. Remember, they are created by the nucleolus. After exiting the nucleus they themselves are responsible for the production of proteins within the cell. Because they are so small, they resembles tiny dots in this picture.
After they exit the nucleus, the ribosomes are often attached to the endoplasmic reticulum (ER).
Let’s review. Which organelle creates the ribosomes?
Ribosomes travel along the rough ER. They are not created here.
There is something else inside the nucleus that makes the ribosomes
nucleus
nucleolus
Rough ER

7. The Rough Endoplasmic Reticulum
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Correct! The nucleolus makes ribosomes.
Ribosomes are created by the nucleolus and then exit the nucleus. After exiting the nucleus, they may begin to create proteins through a process called translation.
The rough ER is called “rough” because it is covered with ribosomes. The rough ER is basically a tunnel system to move ribosomes to other parts of the cell. In this sense, you can compare the rough ER to a subway, and the passengers are the ribosomes.
Click to see the rough ER.

8. The Rough Endoplasmic Reticulum
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Ribosomes are created by the nucleolus and then exit the nucleus. As they exit the nucleus, they begin to create proteins through a process called translation.
The rough ER is called “rough” because it is covered with ribosomes. The rough ER is basically a tunnel system to move ribosomes to other parts of the cell. In this sense, you can compare the rough ER to a subway, and the passengers are the ribosomes.
Since the ribosomes exit the nucleus and flow into the rough ER, the rough ER is attached to the outside of the nucleus.

9. The Rough Endoplasmic Reticulum
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Ribosomes are created by the nucleolus and then exit the nucleus. As they exit the nucleus, they begin to create proteins through a process called translation.
The rough ER is called “rough” because it is covered with ribosomes. The rough ER is basically a tunnel system to move ribosomes to other parts of the cell. In this sense, you can compare the rough ER to a subway, and the passengers are the ribosomes.
Since the ribosomes exit the nucleus and flow into the rough ER, the rough ER is attached to the outside of the nucleus.
See the dots? Those are the ribosomes.

10. The Rough Endoplasmic Reticulum
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Ribosomes are created by the nucleolus and then exit the nucleus. As they exit the nucleus, they begin to create proteins through a process called translation.
The rough ER is called “rough” because it is covered with ribosomes. The rough ER is basically a tunnel system to move ribosomes to other parts of the cell. In this sense, you can compare the rough ER to a subway, and the passengers are the ribosomes.
Since the ribosomes exit the nucleus and flow into the rough ER, the rough ER is attached to the outside of the nucleus.
See the dots? Those are the ribosomes.

11. The Rough Endoplasmic Reticulum
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Ribosomes are created by the nucleolus and then exit the nucleus. As they exit the nucleus, they begin to create proteins through a process called translation.
The rough ER is called “rough” because it is covered with ribosomes. The rough ER is basically a tunnel system to move ribosomes to other parts of the cell. In this sense, you can compare the rough ER to a subway, and the passengers are the ribosomes.
Since the ribosomes exit the nucleus and flow into the rough ER, the rough ER is attached to the outside of the nucleus.
We need to review before we go further.

12. Let’s Review Which step happens first? Click the correct sentence.
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Which step happens first? Click the correct sentence.
How can they exit if they haven’t been created yet?
1st? -- The ribosomes exit the nucleus
1st? -- The ribosomes (free or bound to ER) begin to make proteins in the cytoplasm.
How can they make proteins if they haven’t been created yet?
1st? -- The nucleolus creates ribosomes
Correct! Good job!

13. Click which happens next.
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Click which happens next.
Correct!
1st = The nucleolus creates ribosomes
2nd? -- The ribosomes exit the nucleus
2nd? -- The ribosomes (free or bound to ER) begin to make proteins in the cytoplasm.
How can they travel the ER if they haven’t exited the nucleus yet?

14. Watch the animation. Then click the final step.
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1st step: The nucleolus creates ribosomes
2nd step: The ribosomes exit the nucleus
3rd?? -- The ribosomes (free or bound to ER) begin to make proteins in the cytoplasm.
Well it was the final choice. I hope you got it correct.

15. Remember, we are tracing the path of protein creation.
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Remember, we are tracing the path of protein creation.
1st step: The nucleolus creates ribosomes
2nd step: The ribosomes exit the nucleus
3rd step: The ribosomes (free or bound to ER) begin to make proteins in the cytoplasm.

16. Protein Functions back
Remember, some ribosomes were bound to the ER while making proteins. Proteins are used in a wide variety of cell activities, such as growing hair, carrying oxygen, and digesting foods. Many proteins are created by one cell, but needed by another. Therefore many proteins need to be exported. That’s the job of the Golgi Body (named after Camillo Golgi). Click the arrow to see the Golgi Bodies.
Be patient after clicking the play button. Let the pictures cycle.
The Golgi body receives the proteins that were created by the ribosomes. The Golgi body packages the protein inside a protective envelope called a vesicle.
Doesn’t the Golgi body resemble a stack of pancakes?

17. Vesicles
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Ribosomes travel along the rough ER, but aren’t made here.
Vesicles float away from the Golgi body with finished proteins inside. The proteins are released from the cell and are used throughout the body.
Let’s do some review. Use your worksheet to help you with the answers.
1) Which organelle creates ribosomes?
Golgi body packages proteins
Vesicles move finished proteins
vesicle
Golgi body
Ribosomes are made inside the nucleus by something else
nucleus
Rough ER
Ribosomes create themselves?
ribosome
Nucleolus

18. Review #2 Correct! The nucleolus creates ribosomes.
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Correct! The nucleolus creates ribosomes.
Which organelle transports the proteins made on the rough ER to the Golgi body?
Golgi body packages proteins
Vesicles move finished proteins
vesicle
Golgi body
nucleus
Rough ER
The nucleus holds DNA
ribosome
Nucleolus
The nucleolus makes ribosomes
Ribosomes make proteins

19. Review #3
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Correct! The rough ER transports the proteins made by the ribosomes of the rough ER .
Which organelle creates proteins?
The Golgi body packages proteins
Vesicles move finished proteins
vesicle
Golgi body
nucleus
Rough ER
The rough ER transports ribosomes around the cell
The nucleus holds DNA
ribosome
nucleolus
The nucleolus makes ribosomes

20. Review #4 Correct! Ribosomes make proteins.
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Correct! Ribosomes make proteins.
Which organelle packages finalized proteins for shipment?
Vesicles move finished proteins
vesicle
Golgi body
The rough ER transports ribosomes around the cell
nucleus
Rough ER
The nucleus holds DNA
ribosome
Nucleolus
The nucleolus makes ribosomes
The ribosome makes proteins

21. Review #5
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Correct! The Golgi body packages finalized proteins for shipment.
Which organelle protects a finished protein as it exits the cell?
The Golgi body packages proteins
vesicle
Golgi body
nucleus
Rough ER
The rough ER transports ribosomes around the cell
The nucleus holds DNA
ribosome
Nucleolus
The nucleolus makes ribosomes
Ribosomes make proteins

22. Review #6
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Try again. This is the Golgi body.
Correct! The vesicle protects a finished protein as it exits the cell Now click on the nucleolus.
Try again. This is the rough ER..
Try again. This is the mitpchondria.

23. Review #7
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Try again. This is the flagella..
Correct! That was the nucleolus. Now click on the Golgi body…remember pancakes?
Try again. This is the rough ER.
Try again. This is the mitochondria.

24. Review #8 Correct! That was the Golgi body. Now click on the rough ER.
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Try again. This is the Golgi body.
Correct! That was the Golgi body. Now click on the rough ER.
Try again. This is the Nucleolus
Try again. This is the mitochondria.

25. Review #9
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Try again. The nucleolus does not do this.
Correct that was the rough ER! Now click on the organelle that packages proteins for shipment outside of the cell.
Try again. The rough ER does not do this.
Try again. The mitochondria does not do this.

26. Review #10
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Try again. The Golgi body does not do this.
Correct! That was the Golgi body. Now click on the organelle that creates ribosomes.
Try again. The rough ER does not do this.
Try again. The mitochondria does not do this.

27. Correct. That was the nucleolus. I hope this tutorial was helpful
Correct! That was the nucleolus. I hope this tutorial was helpful. This will be posted on my edmodo for you to review at any time. Keep your handout. Feel free to start over if you would like to do some review.
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