Reproductive Cloning

Reproductive cloning is making an exact copy of an organism that already exists or has existed in the past. In 1997 researchers cloned an adult sheep, Dolly. Dolly was genetically identical to the adult she was cloned from. Reproductive cloning in animals is accomplished by a process called somatic cell nuclear transfer. In somatic cell nuclear transfer genetic material from the nucleus of a donor adult cell is transferred to an egg whose nucleus with its genetic material has been removed. The resulting egg containing the donors DNA must be treated with chemicals or electric current to stimulate cell division. Once the cloned egg reaches a suitable stage it is transferred to the uterus of a female host where it will continue to develop until birth. 

So why clone? Our Biology book openly states that besides the novelty of actually cloning a human for the first time, this concept is likely to be of little practical value in the near future. (Johnson, 405) I think it is important to note that while human cloning seems to carry the most controversy, scientists have been cloning animals for years already.  When doing my internet research I came across some other reasons people give for justifying cloning. Some of the reasons are medical purposes, reviving endangered or extinct animals species, helping infertile couples have children, and cloning stem cells for research. 

When we hear about cloning, we often only hear about the successful cases, Dolly being a bright example of this. Two big issues with cloning are the high failure rate of the procedure and problems during later development. In the case of the famous Dolly she died at age 6 from progressive lung disease and had also contracted arthritis prematurely. The type of lung disease Dolly had is more common in older sheep. Some clones have developed other issues such as kidney and brain malformations and impaired immune systems. 

So the debate ensues, to clone or not to clone? Scientists and researchers and others support cloning because of the wide variety of issues that cloning could help.  Some are against cloning because of the really large amount of unknown variables and the ethical issues. Cloning seems like it could have some very productive places in society but I think we need to make sure we know exactly what we are doing and the implications that it carries. It feels like in the process of learning how to clone we lose sight of some of the moral and ethical issues that arise when not thinking through all the involved aspects of cloning. I do support progress in treating illness and disease. Having suffered from infertility I can even see how cloning may be appealing to some but I cannot say I would have considered this route while we were trying to add to our family. I do not support cloning simply for the novelty of it.

 Sources

Therapeutic Cloning vs. Reproductive Cloning

http://www.pregnancy-info.net/stemcell/therapeutic_vs_reproductive.html  

Accessed March 3, 2013.

Why Clone.

http://learn.genetics.utah.edu/content/tech/cloning/whyclone/  

The University of Utah. 

Accessed March 4, 2013.

Cloning Risks.

http://learn.genetics.utah.edu/content/tech/cloning/cloningrisks/
 The University of Utah.

Accessed March 4, 2013

Dolly the Sheep dies young.

http://www.newscientist.com/article/dn3393-dolly-the-sheep-dies-young.html  

Will Knight.

Accessed March 4, 2013

Human Biology. Sixth Edition. Michael D. Johnson

Stem Cell Research

Parkinson’s disease, leukemia, Alzheimer’s disease, and spinal cord injuries are all diseases or injuries that may benefit from stem cell research, as well as many others. Stem cells are the body’s raw materials, cells from which all other cells with specialized functions are generated. No other cell in the human body has the natural ability to generate new cell types.  Stem cells have the capacity to become whatever type of specialized cell a patient needs. Stem cells come from embryos, adult stem cells, adult stem cells that are altered to have properties of embryonic stem cells, and have also been found in amniotic fluid.  Since it seems stem cell research has great potential to cure debilitating diseases why would anyone object to this research? Controversy comes in specifically with the use of human embryonic stem cells. I chose this topic because I do not know much about it and wanted to research it for myself to see how I feel about the issue.

 

In my research I learned that the most desirable stem cells come from early stage embryos.  These embryos are usually obtained from eggs that were fertilized at in vitro clinics but were never implanted because they were not needed or wanted. This is where the ethical issue lies. Adult stem cells are being used but do not offer as much versatility as embryonic stem cells and are not able to be manipulated as much to produce all the cell types. However advances are being made in adult stem cell research and there is promise in that area. The biggest controversy boils down to when an embryo is actually considered a human life. Those who value human life from the point of conception consider the destruction of the embryo to be killing a human life while research advocates feel that the tiny blastocyst does not have human characteristics.  

So what is the solution?  I see both sides; depending on where your beliefs lie it is a sensitive subject. I feel like we should not specifically make the blastocysts for research but if there are unused embryos and they were to be donated for research so that others may live it feels like it could be positive.  I tried to put myself in the position of having a very sick child or family member and how I would feel if they could be cured by stem cells. Our textbook talked about advances being made in adult stem cell research that may make embryonic stem cell research unnecessary some day, that would be an amazing accomplishment and would solve the ethical issue.

Sources

http://ecordbloodbanking.com/wp-content/uploads/2011/07/Stem-Cell-2.jpg 

Photo credit.  Retrieval date 2-19-2013

Stem cells: What they are and what they do

http://www.mayoclinic.com/health/stem-cells/CA00081

Mayo Clinic Staff.  Retrieval date 2-19-2013

Pros and Cons of Stem Cell Research

http://www.allaboutpopularissues.org/pros-and-cons-of-stem-cell-research.htm 

Retrieval date 2-19-13

Human Biology. Sixth Edition. Michael D. Johnson

Part 2

1.       In this unit there were two activities I was proud of. The first assignment was the discussion on the autism/vaccination link. This activity had the potential to take me out of my comfort zone. I vaccinate both of my children and have felt firmly that I didn’t believe in a link between vaccines and autism. I worried that I would not be able to adequately express both sides of the debate since I felt so strong and comfortable in my stance. I feel like I did a good job with the research and the relaying of my thoughts and ideas. The second activity I am proud of was the molecules lab. That was a really challenging assignment for me! I like things to be black and white and crystal clear and that lab was not. After spending some time pouring over the book and doing some research on the internet and then the video you provided as assistance I felt a bit more comfortable and was able to complete the assignment pretty well.

2.       I have a really good understanding of the cell after this unit. I found it surprising how much I remembered from biology classes I had taken previously, some many years ago. I enjoyed learning about cell activities and how things inside of us work, so much complexity but I felt like I was able to get a good grasp on the information.

3.       To enhance my learning experience I tried to apply what we were learning to my life. In chapter three I read about cells that store fat. I learned that dieting and exercise tend to reduce the amount of stored fat, making the fat cells leaner but that dieting and exercise do not reduce their number. The cells are still available to store fat and that is why it is so hard to keep weight that you have lost off. I have dabbled in different diets and exercise plans to work on my health and this was just a relative connection to me and something that I really didn’t know.  I just knew it is very easy to pack the weight on but so hard to get it off!

4.       I felt most distanced while studying chapter two. I’m not sure what it was about atoms, elements, and the like but I spent a fair amount of time feeling confused.  I had to go over the information a few times to try to really take it in and I still feel like I struggled with some of the chemistry questions on exam 1. In unit one I felt most connected during labs and hands on activity, sometimes the reading was hard to get through but to see the information in action in front of me was really helpful.

5.       I honestly feel like the information in unit 1 was relayed well. There are so many options to reinforce the information and practice it between videos, labs, discussion, etc. I think the only suggestion I would have is something hands on or interactive with some of the chemistry involved in chapter 2 since that is where I feel like I struggled some.

Kitchen Fun!

Milk

*Observe and explain changes occurring in milk due to biological influence.

Place 1/2 cup of milk in a container and place in a warm, dark place for about 3 days.

Hypothesis- I believe the milk will sour, smell badly, and get chunky, due to the warmth and the growth of bacteria.

I placed my milk on the top shelf of our coat closet, it is dark in there and as warm as the rest of the house. The first couple of days I did not see any significant change in appearance or smell. Today was day three and there were some changes, there was a thickish ring around the edge of the cup and the milk seemed thicker in general and definitely did not look as white as the nice fresh milk I had put in three days prior, it had some yellowish tint to it.  I stirred it up and it was thick and smelled slightly sour. When I dumped the milk out there was a thick but smooth white substance on the bottom of the cup that reminded me of yogurt. When I tasted the milk it tasted just fine... just kidding! Ha!

I expected more changes but I think that the closet I put the milk in could have been warmer, there wasn't enough warmth for bacteria to grow more rapidly. Because milk contains bacteria and also lactose which bacteria happen to thrive on, the lactose sugar is changed to lactic acid which tastes sour and causes curdling.

Fresh milk on day one: Nice and white, bubbles, smelled like fresh milk

Milk after three days: Yellowish, ring around cup, thick when swirled and stirred, slightly sour odor.

Juice

*Witness mixing action of molecules and describe the process.

In all pictures far left is room temperature, middle is ice water, and right is boiling hot water. I used Welch's grape juice.

My hypothesis is that the water will mix well into the room temperature and boiling water but maybe not as well into the ice water. 

Preparation

 




Top view after grape juice added

Front view after grape juice added

The grape juice immediately turned all three glasses of water shades of purple. In the first cup with the room temperature water it seemed to disperse well but after a few moments I could clearly see that it was clearer at the top of the glass which can be seen in the picture above. The middle glass is the ice water and again there is a clear separation at the top of the glass. The third cup was the boiling water and from my straight eye view it seemed to mix up the most evenly and was the most consistent in color. I think the colder water made the juice particles move more slowly which is why it took longer to disperse out and in the warm temperature and boiling water it was closer to the temperature of the room temp juice that I used and it was easier for the molecules to mix together. The ice water did seem to have the richest purple color below the separation.

Carrots

*Investigate cellular functions and cellular structures using a carrot.

My hypothesis for this experiment is that the carrot placed in the fresh water may expand some due to the water going into the carrot cells and causing them to burst. The carrot that is placed in salt water will have some shrinkage due to the salt water being hypertonic and drawing water out of the carrot cells.

Initial length and width of carrot pieces:
Piece 1- 4.125 inches long 7/8 inch wide
Piece 2- 4 1/4 inches long 7/8 inch wide

After-experiment length and width of carrot pieces
Piece 1- 4 1/2 inches long 7/8 inch wide
Piece 2- 4 inches long 3/4 inch wide

Carrots in water. Fresh water on left, salt water on right

Carrots prior to water baths.

Carrots after water bath

After 24 hours in the water, there were some changes. On the fresh water carrot the string was tighter then when I had first tied it the night before, the carrot was still very crisp and fresh feeling. The measurements grew a slight bit leading me to believe that some of the cells inside were burst because of the intake of water. Pure water is the most hypotonic solution so water would enter the cells, they would then swell and burst.

On the salt water carrot there was shrinkage. Because the salt water is hypertonic water diffused out of the carrot cells causing the shrinkage. The carrot was much softer then the fresh water carrot and the string had loosened up quite a bit.

Is there a Vaccine-Autism Connection?

Autism is a disorder that is rooted in the brain. Difficulty communicating and relating with others are some observations of an individual with autism. Some symptoms of autism are delays in talking or not speaking at all, and repetitious behaviors, play, and interests that are overused. Autism is frightening and frustrating in that there is no "typical" autism diagnosis . It presents in many different ways and therefore the treatments are individual based and what works for one person may not work for the next. So what causes autism? It is this question that is a pretty hot topic for many parents, physicians, and scientists. A popular viewpoint is that there is a link between childhood vaccines and autism, particularly the MMR vaccine and an ingredient that has been used in vaccines, a mercury based preservative called thimerosal. 

The viewpoint that vaccines have no bearing on autism cases is shared by professionals and parents alike. The Center for Disease Control and Prevention is firmly established in their belief that there is no link between autism and vaccines. The CDC states that evidence from several studies examining trends in vaccine use and changes in autism frequency fail to support an association between thimerosal and autism. It is worth noting that in 2001 thimerosal was removed or reduced to trace amounts in vaccines. When reading up on the causes of autism, thimerosal was consistently discussed as a possible cause. After thimerosal was removed from vaccines there was not a decrease in autism cases, which one would expect.

There are a number of parents and groups who share the viewpoint that there is a link between vaccines and autism. Some information out there that may support this viewpoint is that children that develop autism often do so after childhood vaccinations and also that vaccinations contained thimerosal at one time. Another type of mercury, methyl mercury found in nature and in fish that we eat has been shown to have harmful side effects resulting in intellectual and mental health problems. Methyl Mercury is not the same mercury that was used in vaccines but it is believed that some doctors and researchers drew the conclusion that thimerosal must also cause a similar side effect and may result in autism. There is so much fear surrounding autism because it is not known exactly what the cause is. I think it is safe to say until they are able to find the cause and there is no doubt the debate will continue. With so much information available at our fingertips it's not hard to understand where the fear comes from.

My personal feeling is that vaccines do not cause autism. With so much research showing the contrary I find it hard to believe the reasons that are presented by those who believe there is a link, the supporting information seems outdated and unproven. I realize that autism cases are on the rise but I just can't fathom if vaccinations are causing autism, how are so many children receiving the same vaccines with no resulting autism? I did my own research and my children have received their vaccines to protect them and the other members of our community. I can understand the fear that surrounds the unknown and I do not judge parents who decide against vaccination.

Interestingly enough with the differences that exist between the viewpoints they all seem to come back to science. Those that believe there is no link rely on the results of studies disproving that vaccines cause autism while on the other side it is a lack of a cause or proof beyond a doubt that vaccines do not cause autism that drives their thoughts and decisions. With so much information available at our fingertips I think it can be really hard to make an educated decision without having any doubts or fears. A well known celebrity Jenny McCarthy has been very vocal in her belief that her son's autism was caused by his vaccinations. With information coming at us from so many sources, I think the ultimate answer is for each parent to do their own research and make their decisions to the best of their ability. For myself the information against vaccines is not strong enough to sway my decision.

Sources

Concerns about Autism. CDC.

http://www.cdc.gov/vaccinesafety/Concerns/Autism/index.html

Autism-Vaccine Link: Evidence Doesn't Dispel Doubts. Martin Downs, MPH.

http://www.webmd.com/brain/autism/searching-for-answers/vaccines-autism

Do Vaccines Cause Autism? Christine Gorman.

http://www.time.com/time/magazine/article/0,9171,1003673,00.html

Autism- Topic Overview. WebMD.

http://www.webmd.com/brain/autism/autism-topic-overview