Lesson 1: What is cloning?
Major objectives
Students will be able to improve their decoding and reading skills
Students will be able to define cloning
Materials
News articles on cloning from various sources:
New Scientist Cloning Section
www.newscientist.com/hottopics/cloning/cloning.jsp
HumanCloning.org
www.humancloning.org
Dictionary
Vocabulary word search sheet (handout 1)
Sentence strips
Procedure
Students will be assigned one short cloning related article to read on their own. They will be asked note any words that are new and define them.
Next they will be required to write a one-paragraph summary of what they have read. They will then read this summary to an assigned partner who in turn will share their summary of a different article.
Each partnership will then be required to define the terms listed on the vocabulary sheet.
The teacher will ask each group to say out loud the definition of one of the vocabulary terms.
Finally, each group will use the sentence strip to write out one thing they already new about cloning, one thing they learned about cloning and one question they still had about cloning.
Closure
Each group will read these aloud and the teacher will post the questions on the blackboard. The class will revisit these questions at the end of the unit and hopefully all the new questions would be answered.
Handout #1
Introduction to Cloning
Objective: write in the meanings of the vocabulary words and then find them in the puzzle.
A H B L A D N Q B E X Y Z J R X K E Y L N L E G D
R E L L G B V F O U C I P T H W Z T R N T L K Y M
I M N P C W P D F T C K E T T B I W Z H B E E M L
H X G E M L A L S Q Z C G Q H D J A E T Y C X L U
D N L G O K G T I U L B P L E J Y R I H S M M G D
R L K I V E I P Y E O L I R P U A Q I B K E E X E
S U X F B A S I Y R X K E E C P S Q R K Q T U F Z
K D P V C O X F F T B H A J E F F O Y T R S O B H
U M P T H L R Y T F G B K U Q Z A D M Q M F U K O
A D N S A Q V X K A J N T F W G T U P A T J J I K
F N R B G M T P S F K I E N C O L J L M T E N E G
T E D E E C B E X U C N C F L V O P E S Y I M M B
J B I T E M T J U C N C D E O J V Q H S D Z C I K
Q T N L N X D D L P U O R U N X M O O Z O Q P A W
M A J O L A D O A R H J I E E X O X H I E S E A K
N Q J P M F N R E F S N A R T C I T E N E G L C B
P B Z E D I B I M O Q S G L O N G J G I L L O O R
I P O N N L S I B Y Y A F L L R B N O O Z F E W Y
C R F G P I O W R M D I I H J K A U M P H O N Q V
I S A X M Z B M A W O F Y G Q R M E T F P T J H W
N W N U C L E U S L F C Z A Q X A Q X V Q A L Y X
M I N P L R X X L G R J E T F U Y P K D K C K U M
X J W G J P L T A R H E B R R L R Y K J T L V I I
L U W T S S F H R F L O H P Z G K T H D T Z X L I
A A Y S M W W A T T G T U F S G G X Z E M A M N A
CELLS-
CLONE-
GENE-
GENETIC TRANSFER-
HEREDITY-
NUCLEUS-
RECOMBINANT DNA-
SOMATIC-
STEMCELL-
THERAPEUTIC CLONING-
TWIN-
Lesson 2 : What is Cloning?
Main Objectives
Students will be able to define cloning
Students will use directed reading to improve their reading comprehension skills
Students will improve their ability to use the Internet
Students will be able to describe the process of reproductive cloning
Materials
Access to a computer for all students. (Alternatively, the teacher may print the website pages needed and make a copy for each student. This does not work as well because there are short video clips that are useful.
http://gslc.genetics.utah.edu/units/clonin/whatiscloning
Directed reading sheet (modified if not using a computer)
Procedure
Directed reading is a method used to help students focus on what they are reading. Some students may have to have their vocabulary sheets to use as a reference.
Students will go to the following web site and fill in the directed reading sheet
Directed Reading Sheet #1 (adapted from middleschoolscience.com)
1. _______________ is the creation of an organism that is an exact genetic copy of another.
2. There are human clones among us right now. They were not created in the lab, they are called __________, created naturally.
3. ______________________ is the relatively low-tech version of cloning. This technology mimics the natural process of creating identical twins.
4. Artificial embryo twining uses the same approach, but it occurs in a ________ instead of a mother’s body.
5. Somatic cell nuclear transfer was a method used to create _____________.
6. A ________ _________ is any cell in the body other than the reproductive cells.
7. It’s the difference in our ________ that makes us unique.
8. To make Dolly, researchers isolated a _________ from an adult female sheep. Next, they _____________ the ___________ from that cell to an egg cell from which the nucleus had been removed. After a couple of chemical tweaks, the egg cell. With its new nucleus, was behaving just like a freshly fertilized _____________. It developed into an ________________, which was implanted into a ________________ and carried to term.
9. ________________ (was the first ever mammal to be cloned from an adult somatic cell.
10. Play the natural reproduction movie for this question. Because the offspring contains a combination of the two sets of parent’s chromosomes, it is not genetically identical to either parent but is, instead, _______________.
11. Play the somatic cell nuclear transfer movie for this question. The somatic cell is ______________ in a media that causes it to ________ __________ as an udder cell.
12. An egg cell is __________ from a different animal. The egg cell’s __________ is removed.
13. The egg cell and the somatic cell are _____________ using an ___________ __________.
14. Go to this web site and follow the instructions
http://gslc.genetics.utah.edu/units/cloning/clickandclone/
List all the six steps in the “click and clone” procedures
1._____________________
2._____________________
3._____________________
4._____________________
5._____________________
6._____________________
15. What color is the cloned mouse? ______________.
16. In the real mouse cloning experiment, what was the name of the first born survivor? ___________________.
Lesson Three:Performing Recombinant DNA Technology Lab
Main objectives
Students will be able describe the process of recombinant DNA technology
Students will simulate the process of transforming bacterial DNA using recombinant DNA technology.
Instructional Input
Bacterial cells are prokaryotic, that is they are single-celled organisms that do not have a nucleus. Since there is no nucleus to hold the chromosomes, bacterial DNA is found free in the cytoplasm. Bacterial DNA can be found in a circular structure called a plasmid.
Recombinant DNA is a molecule formed when fragments of DNA from two or more different organisms are spliced together in the laboratory. Moving genes from the chromosomes of one organism to another is called genetic engineering. Today genes from human chromosomes can be routinely transferred into bacteria, thereby ‘cloning’ the gene.
In this activity students will simulate the process by which DNA from a human (the gene that codes for growth hormone) will be spliced into a bacterial plasmid that has been extracted from the bacterium
Escherichia coli
(E. coli). Please refer to Figure 1
A restriction enzyme, in this case EcoRI is used to cut out sections of DNA wherever the specific sequence CTTAAG occurs in the DNA molecule. It cuts it between the A and G, a site four bases apart on both strands, creating DNA fragments with single-stranded “sticky ends.” Because the two single-stranded sticky ends have complimentary sequences, they can pair up with any other DNA fragment from any other organism cut by the same restriction enzyme.
Please find a diagram of this process at: www.accessexcellence.org
EcoRI is used to cut the growth hormone from the extracted human DNA and then used to cut out the same sequence on the bacterial plasmid. Next the human DNA fragment is inserted into the bacterial plasmid and the sticky ends match up and seal. The plasmid is then reintroduced into the bacterial cell and allowed to grow and divide. If the transformation is a success, then the new cells would produce human growth hormone.
Materials
Paper bacterial plasmid (circular colored paper with at least fifty base pairs, it must include the sequence CTTAAG and the complementary bases GAATTC)
Paper segment of human DNA (this must be another color, and about twenty base pairs long also with the same restriction enzyme sequence)
Scissors, tape, construction paper, poster board
Procedure
Make a handout of the instructional input and have students read it or assign appropriate reading in the text prior to start of this activity.
Make enough bacterial plasmids and human DNA fragments for each group before hand and assign groups.
Have students place the bacterial plasmid in the center of the poster board and have then draw a cell membrane around it. Use the scissors as the restriction enzymes and have students find the sequence of the DNA in the human fragment and have them cut it out and produce the human growth gene with stick ends. Next have students take the bacterial plasmid out of the cell and use the same EcoRI restriction enzyme scissors and cut the plasmid DNA at its one sequence. Then have students insert the human growth factor DNA into plasmid and seal it with tape. The bacteria haw not been transformed. Have students replace the plasmid and tell the students that the bacterial cell can now continue mitosis as normal and produce new cells with the human DNA. They have successfully cloned a gene!
Lesson Four: Position Paper
Main Objectives
Students will be able to develop and articulate an argument for or against human cloning
Students will be able to understand and evaluate scientific and legal literature
Instructional input
From the Report on the President’s Council on Bioethics:
At the first Council meeting, the discussion of the ethics of human “reproductive cloning included the following distinctive strands. Some expressed and defined moral weightiness of an inarticulate or “instinctive” revulsion at the prospect of making cloned human children. Others, emphasizing the low success rate and the abnormalities observed in animal cloning, argued that any attempt at cloned baby-making would be (at least for now) a reckless experiment on the child-to-be, given the current state of scientific knowledge and technical facility. Both of these reactions gave the impression that saying no to human reproductive cloning is somehow obvious, or should be.
Perhaps this is true. But others disagreed. For one thing, people who are repelled by the prospect of cloning human beings are concerned not simply or primarily because the procedure is unsafe or might not work; their objection is to the results of a perfected cloning technology, and to a society that permits or embraces the creation of cloned human children. Moreover, the objection based on safety is not really an objection to cloning as such and may in time become a vanishing objection. Furthermore, several members believed that “moral repugnance” was an unreliable and untrustworthy guide to sound moral conclusions, and that, in any case, it was imperative that we try to articulate reasons or arguments that would justify such strong opposition to cloning.