Polar Bear

The scientific name of the polar bear is Ursus maritimus, which means sea bear.

 The polar bear is considered threatened. Some of the causes of the polar bear being threatened are hunting, pollution, and environmental changes.  Polar bear populations have suffered from various forms of hunting, and even though the practice is now prohibited, polar bears are slow reproducers and their populations are still listed as decreasing. Pollution has a significant impact on polar bears because they have a specialized diet. Polar bears are a specialized species adapted to their specific environment so any environmental change has a dramatic effect on the population. Scientists say that even minor changes in their habitat will have far reaching negative effects and that mainly the polar bear is threatened because of melting and shrinking ice pack

Photo credit : http://nelsonndhs.org/Per2_Fall_2010/Arctic%20Animals/polar_bears.html

 

Polar bears live in the arctic territories of North America. They are found in Canada, Russia, Norway, Denmark, and in Alaska in the United States. 

Interesting facts about polar bears:

Only humans prey on polar bears.

Polar bears primarily eat seals.

Paw pads with rough surfaces help prevent polar bears from slipping on the ice

Adult females often weigh between 500 and 600 pounds, and adult males can weigh between 720 and 1700 pounds.

Polar bears are the largest of all bears

http://en.wikipedia.org/wiki/Polar_Bear Wikipeida. Retrieved April 30, 2013.

http://www.bearlife.org/polar-bears.html Bear Life. org. Retrieved April 30, 2013

SAVE THE POLAR BEARS! 

Why should we save the polar bears? Polar bears are beautiful animals that serve an important part of the ecosystems in which they live. 

Photo credit: http://www.bbc.co.uk/news/science-environment-11986236 BBC News. Retrieved April 30th 2013.

If polar bears were to become extinct, human food supply and commercial fishing could be affected. No species including humans, lives without depending on others. 

Photo credit: http://www.prlog.org/11394087-death-of-knut-the-polar-bear-re-opens-zoo-debate.html. PRLog. Retrieved April 30th 2013.

If polar bears cannot adapt to changing climates, they might face almost total extinction by the end of the 21st century, with about 66% of them disappearing by 2050.

Photo credit: http://www.nwf.org/Wildlife/Wildlife-Library/Mammals/Polar-Bear.aspx. National Wildlife Federation. Retrieved April 30th 2013.

 Photo credit: http://www.polarbearsinternational.org/media/images/polar-bear-waiting-ice. Polar Bears International. Retrieved April 30th 2013.

Polar bears provide diversity and beauty to the planet. As a unique species, they can never be replaced once extinct.

 Photo credit: http://www.dailygalaxy.com/my_weblog/polar_bear/. The Daily Galaxy. Retrieved April 30th 2013.

Human Impacts

Unit Paper 4

1. I think my worldview falls between the Stewardship worldview and the Environmental wisdom worldview. I think a healthy balance between the two would be successful; we cannot deplete all the resources of the world simply because we have the power to. We have to make smart choices and engage in sustainable use. 

2. Four causes of environmental problems are population growth, unsustainable resource use, poverty, and excluding environmental costs from market costs.

3. The environmental Pioneer I would choose would be Rachel Carson.  I am impressed that she launched the modern environmental movement and I would like to learn more about the threats of toxic chemicals. I also appreciate that she is the only woman listed and that she made such a big contribution.

Discussion 3

Helicobacter pylori

Helicobacter pylori, commonly referred to as H. pylori is a microaerophilic bacterium found in the stomach. I didn’t know what microaerophilic meant and upon looking it up learned it is a microorganism that requires oxygen to survive, but requires lower levels than are present in the atmosphere. The shape of H. pylori and the way it moves allows it to penetrate the stomachs protective mucous lining, they can also attach to cells of the stomach causing inflammation and the production of excess stomach acid. H. pylori often presents with symptoms similar to ulcers or gastritis. Symptoms can include gnawing or burning abdominal pain, weight loss, appetite loss, bloating, burping, nausea, vomiting, and black tarry stools.

Photo credit: http://www.worldngayon.com/wp-content/uploads/2012/01/Helicobacter-pylori.jpg Retrieved April 29th 2013.

Treatments for H. pylori include antibiotics, medications that can reduce the amount of stomach acid, and surgery to treat ulcers that result from the disease. The best recommended treatment is prevention because doctors do not fully know how the bacteria is spread so there are no guidelines for preventing it. Scientists do believe the infection may be contracted through food and water. Something I found very interesting about this illness is that most people infected with the bacteria never have symptoms or problems! Over eighty percent of people infected do not exhibit symptoms. Infection rate in the United States is between twenty to thirty percent and much higher in impoverished countries and in economic groups characterized with crowded living conditions, poor sanitary conditions and unclean water.

I think as we forge forward infectious disease may play a huge role in our lives. There is already a lot of talk and research involving “super bugs” that are resistant to very strong antibiotics which I do think has a lot to do with over usage of antibiotics.  I also think as technology continues to advance we will be able to treat more and more diseases but there can be so many unknowns. I chose H. pylori because I was working with a woman whose son contracted it and it was a complicated case. He went through a lot of treatments and inpatient hospital stays before he was finally a fully healthy teenager again. I didn't really understand the disease and wanted to learn more. 

Sources

http://www.emedicinehealth.com/helicobacter_pylori_h_pylori/article_em.htm   

Wedro, Benjamin. Retrieved April 29, 2013.

http://en.wikipedia.org/wiki/Helicobacter_pylori  Wikepedia. Retrieved April 29^th 2013.

Unit 3 Reflections

Lipodissolve

Lipodissolve is an increasingly popular "fat melting" procedure. In this procedure patients are injected with phosphatidylcholine and deoxycholate which act to break down fat cells.  The injection can include other substances such as antibiotics, vitamins, and hormones, there is no standardized list. The two active ingredients in Lipodissolve have been approved for use in other medications but have not been approved as fat dissolving drugs. Because the two active ingredients are approved by the Food and Drug Administration, clinics can legally administer Lipodissolve. 

Photo credit: http://idealimageclinics.com.au/lipodissolve.html Retrieved April 17th 2013.

While doing research I learned that Lipodissolve does not require anesthesia, is relatively painless, and does not require any downtime after injections. Benefits can typically be seen after 3 weeks of injections, some patients report changes while others do not. Lipodissolve can cost anywhere between $375 to $1500 per treatment. Some side effects that have been reported are swelling, skin blistering, pain, and blackened skin in some people. In my reading it wasn't clear where the fat goes once dissolved, some believe it is excreted from the body naturally and other researchers suggest it migrates to other areas of the body with fat cells including arteries, which to me was kind of frightening! 

So should I run out and get some Lipodissolve? The Food and Drug Administration has called Lipodissolve "just another example of unapproved drugs for unapproved uses." (Johnson, 81) Being overweight I can see how this procedure would appeal to people but I am concerned with it being a newer product and not having a whole lot of studies and outcomes. The FDA is keeping an eye on Lipodissolve they did approve a clinical trial back in 2007 which was expected to provide the first date on the effectiveness and safety of Lipodissolve. I think I will pass on this procedure until there is more information available. 

Photo credit: http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm206240.htm Retrieved April 17th 2013.

Sources

 Consumer Guide to Plastic Surgery. Foder, Peter.  http://www.yourplasticsurgeryguide.com/liposuction/lipo-dissolve.htm  Retrieved April 17th 2013.

FDA http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm206240.htm Retrieved April 17th 2013.

Part 2.

1. I am actually most proud of the chicken leg dissection. I was not able to get to it until the day after it was due, but it was really neat to see the tendons and muscles and bones that we had been learning about. Hands on seems to help so much to bring clarity to what we are learning about. 

2. I enrolled in BIO 156 as a prerequisite for the nursing program. I had taken Beginning Biology many years ago and needed a more recent biology course.

3. I felt pretty prepared for this experience. I have medical background and I feel like I am a decent student. I understand the expectations of college courses. 

4.The only thing that changed my experience some was personal life related. We became very short staffed at work and I did a 7 week switch from nights to days which put some restrictions on the time I had been devoting to Biology and my other class, it took some adjustments. 

5. I haven't struggled too much this semester. I will say this last exam was the most difficult for me thus far. 5 chapters was a lot of information to get familiar with and retain a lot of small details. If I could redo I would have started studying for the exam sooner. I think the learning tools you provide for us are more than adequate. 

Chicken Leg Dissection

Procedure:
Put on gloves and collect your tools.
Thoroughly rinse and dry one chicken leg. Place it in the dissecting tray.

Lab Assistant.

Examine the outside skin tissue. This is the epidermis and the dimples are where feathers emerged. Using scissors and forceps.

Cut the skin and peel it away from the muscle.

Notice the clear connective tissue that holds the skin to the muscles. As you peel off the skin, you may need to cut away some of this connective tissue. Work slowly and carefully with scissors and forceps until all skin is removed.

Describe how the connective tissue looks and feels. What type of connective tissue is this? The connective tissue looks shiny and flimsy and is stretchy. It feels very smooth. This is epithelial tissue.

Observe, with your naked eye bundles of muscle tissue surrounding the bones. Separate the bundles of muscles by separating them out with your fingers. Begin by inserting your thumb into the muscle of the lower leg. You will need to push forcefully through the shiny lining (called fascia) over the muscle, but it will give way at the natural separations between the muscle bundles. Continue separating the muscle into bundles by forcing your thumb and fingers through the muscle until you are able to distinguish several separate bundles.

Describe the arrangement of the muscle bundles. The muscle bundles are thick and close together. 

The strong, shiny, white cords, called tendons, hold the muscle to the bones. Some of these tendons will pull away from the bone as you separate the muscle bundles. Use a probe, if needed, to find the tendons of the chicken leg. Using the dissection scissors, cut across the tendons at Line A (Figure 1). Observe the numerous tendons and pull the freed muscles down and away from the bone, as if you were peeling a banana. Careful you don't cut any ligaments that attach bone to bone. Look closely at the ligaments.

Examine the two bones in the lower leg. The large bone (Bone A) is the tibia. The small, toothpick-like bone (Bone B) is the fibula.

 What sort of connective tissue are tendons composed of? Tendons are composed of fibrous connective tissue.

Remove a single muscle by cutting the tendons and peeling the muscle away from the bone.

What sort of muscle tissue is represented? How do you know? This is skeletal muscle because it connects muscle to bone.

Nerves are generally thin, threadlike white strands found between the muscle and the
nearest bone. Look for the nerve in your specimen. Did you find them? I saw some very thin white that might have been nerves but it was kind of hard to tell. 

What is the physical difference in the tendon of the insertion when compared to the origin? The insertion was longer and thinner then the origin.

Remove all remaining muscle to expose the bones of the chicken leg.

What is the soft material inside a bone? The soft material inside a bone is marrow. 

Name three specific types of cells present here. Do not break the bone; it is sharp! Osteocytes, osteoblasts, and osteoclasts.

Name three functions of bone. Three functions of bone are movement, support, and protection.

Cut onto the hinge joint by cutting into the top of the covering of the joint from the femur side. It will become apparent that you must remove the knee cap area to expose the menisci and ligaments within. Pull up on the knee cap area and cut through it with the scissors. You will have cut through the bursa, a sac that acts as a shock absorber for the knee joint. These are found in every joint.

Pull the covering back and look into the inside of the joint. You will see more white bands of ligaments holding the bones together. Observe the shiny, white layer covering the ends of the bones is cartilage. It helps the bones slide smoothly when the leg bends.

Bend the specimen at Joint B (Figure 1) and rotate the femur in all directions. Remove the muscle that covers Joint B by cutting parallel to the femur, upward toward the backbone. Remove pink muscle tissue until you see a shiny white sheet of ligament that covers the joint. Present is an exterior ligament that holds the femur in the hip socket

What type of connective tissue composes the ligaments? Ligaments are composed of dense connective tissue.
Figure 2 is provided in a separate document.
Label Figure 2 with the names of the joints you observed and the motion they make.

On Figure 2, sketch one muscle origin (the name of the bone indicates the insertion) and one muscle insertion you can see in the leg.

Hinge joints allow for movement on one plane. 

Ball-and-socket joints permit even wider ranges of movement. The rounded head of the bone fits into a socket, allowing movement in all planes. 

Unit 2 Reflections

Unit 2 Reflections

A topic that I felt engaged by in unit two was chromosomal alterations, specifically Down syndrome or Trisomy 21. I have recently been following two family blogs who have young children with Down syndrome. I enjoy reading both of these blogs and wanted to understand more what Down syndrome is and how it affects individuals. I think sometimes as a society in general we are afraid of people that are different from us and the unknown. Through these blogs I have learned these children are just like mine with the exception of having some medical issues that can be quite serious, however they are just like other children playing, enjoying life, and just being children. 

Down syndrome or Trisomy 21 is caused by inheriting an extra copy of the twenty first chromosome.  Some interesting information I learned while doing my research is that Down syndrome is the most common chromosome abnormality in humans. The CDC estimates that yearly one in 691 births results in a baby with Down syndrome, I had no idea how prevalent Down syndrome is. Some characteristics of Down syndrome are developmental delays that can be mild or very profound and distinct physical features such as a flat facial profile, an upward slant to their eyes, small ears and a protruding tongue.  Some risk factors for Down syndrome include advancing maternal age, having had a child with Down syndrome or parents who are carriers of the genetic translocation for Down syndrome. I was aware that advanced maternal age was a risk factor but didn’t know about the other potential causes.  

Photo credit:  http://kgiegler.wordpress.com/2011/03/06/downs-syndrome-101/ Retrieved March 26, 2013

Photo credit: schoolworkhelper.net/down-syndrome-causes-symptoms-treatment   Retrieved March 26, 2013

The outlook for individuals with Down syndrome has increased drastically in recent years. This is due in part to better medical treatment and social inclusion. Life expectancy is still reduced compared to the normal population. An individual with Down syndrome could live to age fifty and beyond depending on the severity of their health problems. From the two blogs I have read I understand there are many challenges that come with raising children with Down syndrome but also immeasurable joy. Down syndrome is not something that needs to be feared, it can be managed and the individuals can lead fulfilling lives. 

Sources

Wikipedia http://en.wikipedia.org/wiki/Down_syndrome  Retrieved March 26, 2013 

Down Syndrome, Sietske N Heyn PhD, http://www.medicinenet.com/down_syndrome/article.htm Retrieved March 26, 2013

About Down Syndrome, Kids Health http://kidshealth.org/parent/medical/genetic/down_syndrome.html  Retrieved March 26, 2013

Part 2. Thinking about the course

1.       The assignment for unit 2 that I am most proud of is my unit paper. I really felt engaged by the topic I chose and enjoyed learning more about Down syndrome. I had a personal interest in it which seems to add to the enjoyment of learning about a subject.

2.       I feel like I now have a pretty good understanding of mitosis and meiosis. While studying for my exam it seemed to come together better for me. Some of the phases etc are still confusing but I think I have the basics down.

3.       During this unit I made flashcards to study the terms and spent a good amount of time on the end of the chapter reviews. Those reviews are very thorough and seem to help my understanding and help me to know where to focus my time.

4.       I felt most connected with the course during this unit while learning about the inheritance of traits and some of the disorders. I liked learning about how we as individuals get our phenotypes; it’s not something I have put much thought into prior to this Biology class. I also like reading about the background of the disorders, you hear about people who have them but I haven’t spent much time understanding them.  While I enjoyed learning about the traits I think I felt disconnected while learning the way the traits come to be, using punnett squares and trying to figure out how and why things cross was confusing for me.

5.       I think just like in Unit 1 that you offer us plenty of different opportunities to learn and review the material. I had some personal things change during this unit with my work schedule etc that provided extra challenges for me and I feel like I didn’t spend as much time on the material as I could have.