Prompt 3: "Can't live with it, can't live without it"

Beginning on page 49, Dr. Moalem discusses the importance of the sun to Earth's living organisms. He describes our relationship with the sun as a "can't live with you, can't live without you" sort of situation. This relationship with the sun is represented by Big Idea 2: Biological systems utilize free energy and molecular building blocks to grow, reproduce, and maintain dynamic homeostasis, because it demonstrates how organisms gain energy and resources from their environments to function and maintain internal conditions suitable for life.

 

Explain why living organisms "can't live with" the sun at times and "can't live without" it at other times. Discuss multiple factors…Hint, think about a process we have studied this year. Also include vitamin D, cholestrol, and folic acid as a part of your response and discuss the role/importance of each, and the connections between these terms.

 

Explain the adaptation of skin color. Include in your response, melanin, melanocytes, and ApoE4.

 

Do living organisms also have a "can't live with, can't live without" relationship with ApoE4? Provide evidence for your stance by conducting research on the role of ApoE4. Relate to vitamin D and cholesterol. This is a good website to get some ideas going!! http://www.life-enhancement.com/magazine/article/2695-apoe-epsilon-4-risk-factor-for-alzheimers-disease-why-is-it-still-in-the-gene-pool

 

(Michelle Liang, mliang4@students.d125.org)

 

Prompt 3: Expand on the Whys - Big Idea 1

On pages 205-206, Dr. Moalem sums up his book with the toddler analogy. After completing the book, our understanding of the impact of diseases on our evolution should have become more nuanced and complete. Dr. Moalem addressed hemochromatosis, malaria, Type 1 diabetes, the common cold, as well as others. But like all books, Dr. Moalem cannot address every single disease that exists and the impact that it had upon our evolution, our Big Idea 1. That would become an infinitely long book. But what can be done is to take the knowledge that was given and use it to expand what we know.

Look up a disease of your own choosing. Find if the disease may have offered a selective advantage in certain regions. What ethnic groups are most affected by your disease? In a well-developed paragraph (or paragraphs), delineate your findings.

(Gabriel Antoniak gantoni4@students.d125.org)

Prompt 3: Tolerance and Big Idea 3

On page 178, Moalem explains physiological tolerance. Physiological tolerance is a form of gene expression in that the presence of a drug, medicinal or otherwise, will cause the promotion or suppression of the specific genes that help process the drug. This relates to Big idea 3: Living systems store, retrieve, transmit, and respond to information essential to life processes. When your body receives a substance like alcohol, it will promote the production of the enzyme alcohol dehydrogenase to help break down the alcohol. Drinking a lot will keep the production of that enzyme high, but when you stop drinking, your body will slow down production. Tolerance can be problematic, as when a patient is taking a prescribed medication, but the effects are no longer potent enough to be useful, or if a drug user is become tolerant and must take more of a drug to get the same feeling, which can lead to overdose. 

Explain the relation between tolerance and metabolism, like in the example of high alcohol dehydrogenase levels leading to faster transformation of ethanol to acetaldehyde. Also, how is tolerance related to dependency?

What happens to your body when you become tolerant to alcohol, cocaine, or oxycodone? Why do drugs such as LSD and marijuana not cause tolerance?

(Posted by Tina Tian, ttian4@students.d125.org)

prompt 3

On pages 85-87 Moalem talks about how the defense mechanisms of crops can also be poisonous to humans. This relates to big idea #4 (biological systems interact, and these systems and their interactions posses complex properties), because while a certain toxin can defend a plant from attack it can also make it inedible.
In the greater view of ecology is it possible to protect crops without making them toxic to humans in some way? Research if this method would be viable  in the real world and what effects it would have on the environment.
(Tom Shaw tshaw4@d125.students.org)

Prompt 3

On page 119, Maolem begins to discuss how microbes move around from host to host, and how some microbes such as the cold virus need their host to be relatively healthy in order to survive and continue to spread to new hosts, while others such as malaria can attack with no limits at its host. This is a technique used by the microbe to ensure that it has the best chance of spreading. Expanding on the microbes that do not care for the host's condition, Maolem states that evolution favors parasites who can exploit the host to the fullest. This relates to Big Idea 4 as the microbes are interacting with the host.

Research another virus, and state to what extent the virus attacks the host. Also, how can the virus be contained? In the text Maolem also states that outbreaks such as Cholera 1991 in South America can be contained with simple procedures such as water safety, or malaria with mosquito nets. While this definitely sounds possible, given the current state of some areas, is it viable/possible to truly contain these outbreaks if and when they happen?

(Name- Ray Lee, Email- rclee4@students.d125.org )

Prompt 3

On page 102-103, Moalem talks about the actions of a tiny worm called dicrocoelium dentriticum that lives inside sheep and cattle. Moalem shows the worm's cycle of life from egg to offspring and how they return to a different host if their first host dies. The worm's offsprings will travel through the feces, snails, and ants. Finally to return by making the ant commit suicide. This relates to Big Idea 4: Biological systems interact, and these systems and their interactions possess complex properties.
With the dicrocoelium dentriticum in mind determine why living inside of a sheep or cattle provides the worm with selective advantages. Keep in mind the rules of survival we learned such as living space. Next determine how the worm has the ability to take over the ant's nervous system causing the ant to act uncharacteristically. Does the worm require certain proteins in order to control the ant or is there another mechanism?Also research what selective advantages could a parasite gain from infecting a specific host; for example, what selective advantages are there for dicrocoelium dentriticum to infect the cattle or sheep as opposed to a human. Use these results to come up with a solution to reduce the number of parasitic infections or why these infections benefit the ecosystem in the long run. 
Jimmy Wang jimmypelewang@gmail.com

Chris Yao's Ultmate Prompt 3 - Infectious Diseases

On pages 118-120, Dr. Maolem describes how Paul Ewald, a leading evolutionary biologist specializing in infectious diseases, believes that the main factor of an infectious diseases virulence is the method the pathogen moves from host to host. One way microbes move from host to host is through close proximity allowing transmission through the air or close contact. Ewald describes how diseases using this particular mode of transportation are not particular virulent because it is a selective advantage leaving the host capable of moving and thus allowing them to move close to other potential hosts so the infectious agents can survive and reproduce. Another way microbes are transmitted is by using an intermediate organism to carry them to hosts, these organisms include mosquitoes, flies, fleas, and other similar organisms. Since these microbes don't need their actual host to spread, they are more virulent then the first type of disease. It is a selective advantage for diseases in this category to create as many infectious agents as possible as the more microbes there are in our blood, the higher the chance for an intermediate organism, like a mosquito, to pick up and further spread the disease, allowing it to survive and reproduce. The third type of transmission Ewald discusses is transmission through food or water. This case is exactly like the second type and differs only in the fact that the diseases of this category are spread through food and water rather than an intermediate organism. This relates to Big Idea 4: Biological systems interact, and these systems and their interactions possess complex properties.

Choose a different infectious disease to research and explain how it has evolved to produce symptoms that increase its ability to survive and reproduce. Be sure to include how your disease spreads in your response. Additionally, research what is currently being done to treat patients with your disease and describe how these treatments combat the disease and its spread. Finally, since the use of antibiotics can cause the disease to evolve to become resistant, discuss whether or not they should still be used, if not, provide and support an alternative solution.

Chris Yao chyao4@students.d125.org

Prompt 3: Rana Sylvatica and Big Idea 3

On pages 40 - 44, Dr. Moalem discusses the wood frog, Rana sylvatica's response to the extreme cold in the winter. In the spring time you can year the mating call of the frog, but in the winter you don't hear it at all. The frog does not hibernate, instead it buries itself under an inch or two of twigs and leaves and freezes solid.

When the temperature rises again in the spring, it thaws the frog, the heartbeat of the frog sparks, it gulps for air, color returns to its eyes, and it stretches its legs and soon returns to the woodlands to find a mate. It's like the frog returned from the dead.

Here's how it works. A few minuets after the frog senses that the temperature is dropping, it moves water out of its blood and organ cells, and pools the water in its abdomen. At the same time, the frog's liver releases large amounts of glucose into its bloodstream. This significantly lowers the freezing point of whatever water remains in the bloodstream and turns it into a kind of sugary antifreeze. The frog in effect put's its organs on ice. This relates to Big Idea 3: Living systems store, receive, transmit, and respond to information essential to life processes.

Keeping in mind how the frog freezes itself, and Big Idea 3, do you think that some day people will be able to cryopreserve themselves? Why or why not? Do you think that someday scientists will be able to mimic this process in the lab to preserve organs for transplant? Why?

(Posted by Sriya Potham, spotham4@students.d125.org)

Prompt 3: Methylation of DNA, Big Idea 4

In the second to last chapter, "Methyl Madness: Road to the Final Phenotype", Dr. Moalem focuses on the role of DNA methylation and gene expression.  The study of environment influences our genes is called epigenetics, which relates to Big Idea 4 (Biological systems interact, and these systems and their interactions possess complex properties).  Moalem provides many specific examples of how DNA methylation in a mother affects her fetus.  Some choices, like a mother's poor choices in her diet during the pregnancy, make her child prone to obesity later in life by giving them the "thrifty phenotype" (Moalem 163).

In other studies with mice, researchers successfully turned off the agouti gene that created a fat yellow phenotype.  They forced two mice with the agouti gene on to have offspring that were thin and brown by feeding the mothers vitamin B12, folic acid, betaine, and choline; compounds found in prenatal vitamins (Moalem 158).  Later, Dr. Moalem also describes some drugs that affect methylation and therefore affect how a gene is expressed, like in the case of azacitidine, an inhibitor of methylation (Moalem 175).

First of all, how and where does DNA methylation occur?  Are the ingredients from prenatal vitamins such as vitamin B12, folic acid, betaine, and choline methyl donors or do they inhibit methylation?  Find another compound that is a methyl donor.  Is it commonly found in a normal person's diet?  Is more methylation a good thing? Why or why not?


Katelyn Noronha, knoronh4@students.d125.org

Prevalence of cancer in certain parts of the world

Moalem describes on page 67 how vitamin D, which we get from sunlight, has shown evidence of inhibiting the growth of cancerous cells. This implies that increased exposure to sunlight can possibly reduce the risk of cancer. In fact, there is recent evidence that shows that vitamin D can help reduce the risk for breast cancer.

This relates to Big Idea 4, that biological systems interact, and these systems have complex properties. If it is true that vitamin D reduces the risk for cancer, then areas where sunlight is more prevalent should have less people affected by cancer.

Research the prevalence of cancer in certain parts of the world and explain if your findings support or goes against the idea that vitamin D lowers the risk of cancer. If your finding goes against this idea, research other factors that explains why certain parts of the world are more susceptible to cancer than others.

(Aaron Chai, achai@students.d125.org)

Prompt #3

      On pages 106-108, Dr. Moalem discusses the parasite Toxoplasma gondii, and the parasite’s effect on humans compared to mice. T. gondii reproduces in cats only, so for the parasite to get back to a cat, it must manipulate a mouse. In mice the parasite nests in the brain and muscles. With chemicals the parasite turns the mouse lazy and fat. Eventually the mouse loses it’s fear of predators. The cat sees the mouse and thinks “dinner”. And that's how the T. gondii gets back into the cat.

      But, the effects of T. gondii are benign in humans, with the exception of HIV patients and pregnant women. Researchers have found that infection may trigger schizophrenia, but it’s also likely that people with schizophrenia are more at risk for getting the parasite than healthy people, since they have behaviors like poor hygiene. The T. gondii infection is like the “chicken or the egg” situation, does it cause the behaviors? Or do the behaviors cause the infection?

     Relating to Big Idea 4, explain the relationship between humans and T. gondii and discuss how the parasite manipulates mice and their relationship. Also pick a side in the “chicken or the egg” situation (infection causes a behavior or the behavior causes it) and provide evidence to why you think your side is right.

      Anna Podber
  (apodber3@students.d125.org)

Prompt 3 Epigenetics in Offspring

On pages 160-161, Moalem discusses the effects of epigenetics on the characteristics of newborns from different species in relation to the environment they are born in. It seems that the environment the mother is experiencing has a direct effect on the phenotypes its offspring displays. For example, a female vole depends on the amount of light it can sense to tell the whether patterns, and depending on the season when she gives birth, the newborn voles will either have thick or short coats of fur. This relates to Big Idea 3 and 4. The methylation of DNA, or turning them on and off, determines whether a phenotype is expresses. Transcription is regulated this way, so if certain genes aren't transcribed, the proteins they code for will not be synthesized. This would cause the absence or presence of certain phenotypes. Also, the methylation in the fetus' DNA is from the mother's responses to the environmental conditions around her, and it provides her babies with a better chance at survival and reproduction.
Pick a species of animal that has exhibited this sort of epigentically controlled offspring phenotype selection, and discuss two or more possible environmental conditions a mother would experience that would affect the characteristics of her babies. Describe these characteristics and how they would be advantageous in the newborns' survival. Also, discuss how the genes for those particular phenotypes could be altered in response to a mother's environment. (ie. methylation or demethylation turns genes on and off which results in a thick or short coat) You may select one of the species mentioned in the book, but please research on a characteristic not explained in it. (ie. thick coats of voles due to variation in amount of light is off limits.) However, you may also find a species not mentioned in the book as well.

(Vivian To vivto4@students.d125.org)

Prompt 3- Lactose Intolerance

            On page 60, Moalem discusses lactose intolerance. He says, “the great majority of the world’s adults cannot eat or drink milk without experiencing a very unpleasant digestive reaction.” I thought this condition was really interesting because I can’t really imagine not being able to eat ice cream or drink coffee. I also didn't really know that so many adults are lactose intolerant. Both my parents can digest lactose, and with further research into my family’s history, I did find out that some of my ancestors were once farmers. Are you or any adult in your family lactose intolerant? Were your ancestors once farmers? This topic of lactose intolerance relates to Big Idea #1. (The process of evolution drives the diversity and unity of life) My ancestors evolved to produce the Lactase enzyme as adults, and it helped them survive and reproduce.

            Look into your family history and try to find some reoccurring occupations of your ancestors; were they teachers, blacksmiths, bakers, or artists? Relate their occupation with a mutation you or your family members have. Explain specifically how this condition may have been favorable for your ancestors’ occupations. Also, explain how this mutation works from a biological perspective.

(Ilakkiya Thanigaivelan, ithanig3@students.d125.org)

Prompt 3 - chemical warfare

On page 78-79 of Dr. Moalem's "Survival of the Sickest", he describes that plants are the biggest manufacturer of chemical weapons in the world. In fact, plant chemistry has the power to significantly impact its' environment from weather to the amount of predators in the area. One such chemical is called phytoestrogen. This chemical mimics the effects of estrogen, a hormone. When animals eat too much of plants that contain phytoestrogen, the compound destroys the animals ability to reproduce.

An example of this is a sheep breeding crisis that occurred during the 1940s in western Australia. Healthy sheep were not getting pregnant. Agricultural specialist confirmed that the phenomenon occurred because of the European Clover (produces phytoestrogen aka formononetin). This occurs when the area doesn't have rain or sunshine, so it limits the amount of predators.

This correlates with Big Idea 1 which relates to natural selection. These plants relate to this big idea because the animals who eat the plants will survive, however, they will not reproduce, so the population for that organism will decrease exponentially. Those organisms who are aware of these types of plants will be the predators who can survive and reproduce off of a different plant.

What are some other types of chemical defense mechanisms that plants use? Please give the scientific name and a description of what the chemical does to its' surrounding environment. Also, can the overload of estrogen in animals causing havoc in reproductive abilities be cured? Please do outside research and explain how organisms can be cured.

Elliot Rosen (erosen3@students.d125.org)

Prompt 3 - Personalized Medicine

          On pages 67-68, Moalem briefly discusses pharmacogenetics, the study of producing pharmaceutical treatments based on a population’s specific genetic variation. The pharmaceutical industry recognizes that certain populations do not respond to treatments as well as other populations. Moalem mentions BiDil, a new drug meant to treat self-identified black patients who suffer from hypertension. BiDil was produced because African Americans with heart failure were not responding to certain heart failure treatments. There was much controversy when the FDA approved BiDil.

          Research another population-specific drug. Discuss the disease or disorder the drug is meant to treat as well as the population for which the drug was created. Why is a personalized treatment required for this population? Was there any controversy related to this drug? Connect your response to anything you learned about personalized medicine from Sam Rhine. Be sure to also connect your response to Big Idea 1 (The process of evolution drives the diversity and unity of life).

(Christine Fanning, cfannin4@students.d125.org)

Prompt entry #3 - ACHOO syndrome- Anzori K.

In Chapter 3, page 58, Dr. Moalem talks about a disease called the ACHOO syndrome.The ACHOO syndrome is an autosomal disease the causes one to have an outburst of sneezes when in sunlight, yet they do not sneeze in darkness. This disease relates to Big Idea I, in which that this syndrome is an example of a evolution that drives both diversity and the unity of life. But what was once a benefactor, is now a disease. Originally, this syndrome helped out our cave-dwelling ancestors clear out any molds or microbes that might have lodged in their noses or upper respiratory tracts. At first, this disease helped out ancestors by removing possible threats to our immune system, but now for some, it poses as a threat to their lives.

 How common is this disease in different parts of the world? How do these kinds of people go about with their daily lives? Do they were special clothing, or perhaps take any specific medication to suppress this bodily response? Also, is this gene for this syndrome located on the X or Y chromosome? What is the locus of this gene? Is this gene seen more in specific places in the world compared to other places in the world?

~Anzori Kuchaidze (akuchai3@students.d125.org)

Prompt #3 Advantages of Being Human

On pages 199-201, Elaine Morgan describes a theory on how humans evolved into how we are today as a species because we were evolved from aquatic apes. Being able to live on water and land would give prehuman ancestors options to avoid predators in the water and land, increasing its chances of surviving and reproducing. The selective advantages of being bipedal are that an ape can move across water well while still breathing. The selective advantage of why our fat is attached to our skin is because it helps keep babies afloat just like dolphins flow smoothly through water.The water ape theory relates to big idea #1, the process of evolution drives the diversity and unity of life. The theory tries to explain why humans evolved the way we did instead of staying 4 legged and fury like many other animals.

Find more selective advantages or disadvantages of how humans evolved to this day for other examples(ex: big heads, shape of human pelvis, opposable thumbs). Also, explain why you think other aquatic animals didn't evolve to become bipedal like we are.Make sure to also state why you think the aquatic ape theory could be a valid way of explaining the origins of many traits that humans have today.

(Eric Huang, ehuang4@students.d125.org)

Prompt #3

In pages 89-91 Dr. Moalem talks about malaria. Malaria is an extremely dangerous disease that kills one million people per year. This occurs most in Africa because the disease comes from mosquitoes that infect the blood. Because the blood goes quickly through the blood cycle it kills painfully through a series of fevers and chills. To combat this, people can get G6PD deficiency. This deficiency may cause death, but it helps to combat malaria. This relates to Big Idea 1: The process of evolution drives the diversity and unity of life. To survive, we eat fava beans that potentially kill us from G6PD deficiency. The more dangerous disease is Malaria so the Africans decide to have the other mutation to prevent Malaria.

Like Malaria, there are many diseases that are more dangerous than others. To prevent malaria some humans take on a genetic disease that decreases chances of malaria. This disease may effect us negatively, but helps us survive more dangerous diseases. Like Malaria and fava beans find a disease that our bodies can prevent using another disease. Research both diseases and explain what they do to the body. Explain how the second disease helps to prevent the more damaging disease.

(Sam Lee salee4@students.d125.org)

Prompt 3

On page 105-107, Dr. Moalem discusses the parasite Toxoplasma Gondii or T. gondii. The parasite reproduces by asexual reproduction during the life of its host. T. gondii is a host manipulator parasite, meaning the parasite manipulates the host (in this case mice and rats) and can get the host to do whatever the parasite wants. When T. gondii get into a mouse via cat droppings, the parasite moves into the muscle and brain cells of the mouse.The mouse then becomes fat and lethargic. The mouse loses the fear of cats and is attracted to the smell of cats. A slow mouse attracted to cats means cat food for the cat which is exactly what the T. gondii want because T. gondii can only sexually reproduce in cats. This question is related to Big Idea 3 (living systems store, retrieve, transmit, and respond to information essential to life processes) as the mice respond to the information from the T. gondii, even though the information is wrong. When the parasite is in a cat, the parasite produces  new oocysts. The oocysts are then excreted from the cat as feces and other animals, including humans, can ingest the oocysts. Ingesting the oocysts causes the animals to become infected since the T. gondii cells are distributed throughout the body by the bloodstream and the T. gondii get inserted inside muscle and brain cells.  Humans can be infected by this parasite by consuming raw meat or handling cat litter. Dr. Moalem mentions that there is increasing evidence that a past infection by T. gondii may trigger schizophrenia in some humans. Schizophrenia is a brain disorder in which patients can be delusional, have hallucinations, disorganized behavior, and more. What T. gondii actually does to the brain is still unclear and whether or not T. gondii causes schizophrenia is also unclear. However, a study conducted by researchers at Johns Hopkins University has shown that mice infected with T. gondii may be helped with antipsychotic medications.

Research another manipulative parasite that may cause certain diseases in humans and explain how the behavior of the parasite can cause the symptoms of the disease. Explain the selective advantage of the manipulation performed by the parasite on the parasite's host. Then discuss whether or not treatments of the disease potentially caused by the parasite might help with treatment of patients infected with the parasite.

(Laura Gu, laugu4@students.d125.org)

Prompt 3 - Family History

In Chapter 3 on page 69, Dr. Moalem writes "there is mounting evidence that where our ancestors came from, how they adapted to manage their environment, and where we live today all combine to have a significant impact on our health." He also states "that specific diseases are more prevalent in specific population groups." Knowing this, much research has been done to further explore correlations between race and disease and why some diseases seem to be more common in particular races. This relates to Big Idea 1: The process of evolution drives the diversity and unity of life. Certain diseases have developed in different races depending on their migration and environments in which they chose to live in. 

Research about your family history and the migration that they have made. Then, use this research to determine what diseases are most common for you ethnicity and why these diseases are prominent as a result of evolution. Lastly, research to see if there is a correlation between certain physical traits that may be attributed to your race and the diseases that are most common due to evolution.

(Dana Morgan, Dmorgan4@students.d125.org)

Prompt 3: Imprinting and the Epigenome: Big Idea 3

On page 168, Dr. Shoalem Moalem discusses methylation and the epigenome. Dr. Moalem specifically cites a 2004 study that showed “interactions between mothers and their offspring after birth provoked the placement of methyl markers caused significant epigenetic changes.”

The 2004 debate lends itself to the popular debate of nature versus nurture. Dr. Moalem believes that the can be found between “nature and nurture.” Interactions between mother rats with their offspring affected the epigenome of the offspring, which changed the offspring’s ability to deal with stress.

Define what the epigenome is. Explain how the epigenome is modified (methylation, acetylation, etc.) Explain how these modifications in the epigenome help regulate gene expression.

Define imprinting. How does the study Dr. Moalem cited relate the epigenome and imprinting? Research and explain another example of how care (nurture) can affect an offspring’s epigenome (nature). 

(Dhruv Luthra, dluthra4@students.d125.org)

Prompt #3 Andrew Komarov

On the first page of Chapter 5, Dr. Moalem mentions the Guinea worm, a parasite which attacks the human digestive system and grows and mates in there. Dr. Moalem describes the surgical process of removing the worm, which includes a very painful process of wrapping the worm around a stick and removing it, often taking weeks, and often leading to death. Dr. Moalem then mentions that former President Carter led a “two decade effort” to eliminate the guinea worm. “According to the Carter Center, the worldwide incidence of guinea worm infections had dropped from 3.5 millions in 1986 to 10,674 in 2005.” 

10,674 infections is still too many, what methods could have helped the limiting of the guinea worm by such a drastic number from 1986 to 2005? What different methods could we use now to try to completely eliminate the guinea worm? Relate this to Big Idea #1, how could the guinea worm spread cross continentally? Hint: (Speciation)

If we stopped all efforts to limit the growth and spread of the guinea worm, would its population begin to grow again or would it stay constant?

( Andrew Komarov, a_komarov@comcast.net)

Prompt #3 The Effects of Aging on the Individual, and the Human Species

Prompt #3 3/23/13 The Effects of Aging on the Individual, and the Human Species

Dr. Moalem introduces aging and the idea of planned biogenic obsolescence in Chapter 8.  Perhaps humans were programmed to die in order to make way for new models, creating room for change (Big Idea #1-evolution), and protecting the group by eliminating individuals who are disease ridden (p. 191). He discuses the rare and quite tragic disease called Hutchinson-Gilford progeria syndrome, which causes premature, accelerated aging in humans.  This aging starts right after birth and someone suffering from this genetic disorder usually does not live past the age of 30.  Researchers discovered that the gene that caused this disorder produces a protein called lamin A.  People with this disorder do not produce functional lamin A, and as a result, their cells deteriorate at an accelerated pace. Furthermore, lamin A deteriorating was linked to normal human aging. (p. 183-184) Later on, Dr. Moalem discusses studies that scientists are exploring to slow the aging process and reverse the cellular damage caused by progeria.  Although the scientists haven’t been able to reverse progeria in humans yet, we can be assured that they are working towards this and towards other ways to reverse or slow the normal aging process (p. 192).

Questions: With all this new research going into preventing or slowing down aging in humans, how does it affect the individual? The species? Might slowed aging in humans actually hurt the evolutionary process by not making room for “new and improved” models?

Rachel Chang (rchang4@students.d125.org)

Prompt #3 Relating to Big Idea 4

On Pages 175-176, Maolem describes the drug azacitidine which treats myelodysplastic syndrome, also known as MDS. Azacitidine demethylates certain genes in blood cells to restore gene expression. The interaction between azacitidine and the DNA of blood cells relates to Big Idea 4: Biological systems interact, and these systems and their interactions possess complex properties.

Research a gene that is methylated and how its methylation causes MDS. Describe specifically how azacitidine demethylates this gene.
Next, research another disease or disorder that is also caused by DNA methylation and how a drug is used to treat it. Compare these results and explain whether or not this information can be used to find cures to other diseases caused by DNA methylation.
Finally, state whether or not demethylation of DNA could be a bad thing and why. References to DNA, gene expression, and cells are recommended.

(Name: Will Han email: wihan4@students.d125.org)

Prompt 3: HERVs

On page 150, Moalem describes retroviruses that found a permanent place in our DNA. They are called human endogenous retroviruses or HERVs. Moalem says that viruses that do not harm but instead helps, increases the chances of survival and therefore may become a permanent part of the gene pool. HERVs relate to Big Idea 3, Living systems store, retrieve, transmit and respond to information essential to life processes, because HERVs relate to DNA and the important role it has on  an offspring’s chance to survive and reproduce.

Moalem says that the HERVs play important roles in human health. What roles of HERVs have been uncovered? What are examples of retroviruses that have found permanent places in our DNA? How do these retroviruses help increase our chances of survival? Also, Moalem says that there’s documented links between HERVs and psoriasis; what is the link/ explain the connection between HERVs and psoriasis?

(Hervy Ong, hong3@students.d125.org)

Prompt 3 - Immune System - Big Idea 4

     On page 12 and 13, Moalem explains specifically how hemochromatosis helps the immune system. This relates to Big Idea 4: Biological systems interact, and these systems and their interactions possess complex properties. In this case, by protecting us from pathogens, the immune system is responsible for keeping us alive.
     If the macrophages have iron, many different kinds of pathogens can take advantage of this iron-filled environment to survive and reproduce more quickly. This is why iron-deficient macrophages in hemochromatosis patients are better at killing bacteria. There is no food for the bacteria in the iron-deficient cells.
     When a macrophage encounters a bacteria, the macrophage will commence phagocytosis. What happens in this process?
     However,  iron-deficient macrophages are not all-powerful, since there are also some pathogens that consume other things besides iron for its food. Please research a bit and tell us about a disease like this (e.g., Lyme disease). What do you think could be the next step for research to find out what we can do to combat these kinds of diseases?
     If someone were to cut you across the forearm with a dirty knife:
            What kind of barriers did the knife penetrate, and what kind of defenses will take over from this point onwards?
            What would you see happening? What would happen both microscopically and macroscopically?
           

(Hugo Lee; hlee3@students.d125.org)

Prompt 3-Water Birth

As some people on the blog have mention, Dr. Moalem discusses Elaine Morgan's aquatic ape hypothesis, which discusses that people may have evolved from a primate ancestor when a group went to live more of their lives near the water. This accounts for the decreased hair on humans, and bipedalism, because the bouyancy force from the water helped the aquatic apes stand on 2 feet. Many human characteristics seem to relate to water, so it is possible that the way we give birth does too?
On pages 203-204, Dr. Moalem states that giving birth in water protects babies from aspiration pneumonia, which occurs when a baby breathes while there is still birthing residue on its face, which can be inhaled and cause infections. Babies only start to use their lungs when they feel air on their faces, but can still receive oxygen from the umbilical cord when they are underwater. Water birthing is also seen as less painful, as far fewer women request epidurals, and it is a much faster process.

Why do water births occur in a shorter period of time? Relating to target one, even if people's ancestors lived in the later, why (besides all of the aforementioned reasons) might water births provide a selective advantage over land births? Is it possible that the babies could get other infections from pathogens in the water, even though they may be avoiding aspiration pneumonia?
(Zachary Rane, zrane3@students.d125.org)

Say hello to my little friend! Prompt 3,

With the population growing at such a high rate and large amounts of waste also accumulating, coming across diseases and life threatening viruses are inevitable. With the vast amount of diseases present, our bodies quickly adapt to become resistant to many of these diseases. Our immune system is able to create antibodies for any particular antigen and place these antibodies in our immunological memory so that we can destroy that particular pathogen much more quickly if it ever invades our bodies again. When antigens, foreign substances in the body, are present, antibodies are created to respond to that particular kind of antigen. That antibody recognizes the antigen and kills it with the help of T cells, which are a type of white blood cells. Once these antibodies are created they are in our bodies forever and we are considered immune to that disease. This relates to Big Idea 3: Living systems store, receive, transmit, and respond to information essential to life processes.

These antibodies can then be passed down from mother to child through a process called passive immunity. Therefore, at birth, the child will be immune to many of the diseases that the mom had antibodies for.

In Survival of the Sickest, Dr. Sharon Moalem addresses the importance of vaccinations which are also a type of passive immunity. Vaccinations allow our bodies to produce the antibodies of many viruses by introducing a weakened version of the virus. Moalem states that, “...we stimulate our immune systems to produce antibodies specifically tailored to defense against that virus” (Moalem 126). These antibodies will protect our bodies and shoot down any foreign invader!

If the antibodies are present in our bodies after we receive the vaccine, why must we be vaccinated multiple times throughout our lifetime? Is it possible to develop a vaccine that does not require more than one vaccination?

If viruses require more than one vaccination, will the antibodies they create be of any help to children if they are passed down from the mother?

Finally, Moalem states that, “...genes can change” (Moalem 126). How do changes in genes affect the antibodies we produce and are there any potential benefits or disadvantages to this? Explain.

(Ted Nowak, tnowak4@students.d125.org)

Prompt 2 epigenome and mothers

On pages 160-162 Moalem looks at how the environment a mother is exposed to might effect its offspring because of the epigenome. This relates to big idea 4 (Biological systems interact, and these systems and their interactions possess complex properties) because the way the enviornment interacts with an organism could change that organisms offspring.
Epigenetics is a relatively new field of study and more about it is being discovered every day. Research and explain a species that is not explained in the book where the mother's exposure to stimulus effect her offspring. Explain how much of the species phenotypes might be determined by epigenetics and how much can never be changed. Could epigenetics effect every aspect of an organism?
( Tom Shaw tshaw4@gmail.com)

Prompt #2 Water-Apes

Dr. Moalem talks of how humans have similar ancestors with apes from pages 198-204. Humans have less hair than other apes and walk on two legs. The theorem is that humans evolved in an enclosed area of water and land. Moalem explains how being on two legs allows humans to stay further in water, having downward noses allow us to dive, and having less hair lets us be more efficient in water. This connects to big idea #1 in which the process of evolution drives the diversity and unity of life. In the way that we have similar ancestors with apes with specific biological functions to make us more efficient in living in specific environments with water, other animals have evolved as well.

Other animals all evolve depending on their environments to increase rate of survival. One example is the finch. The finch evolved into three species with different beaks. These beaks, depending on where their environments were, helped them eat their food. Like the finch and humans, determine a specific animal and environment. Research how that specific species evolved and find how that biological function increases the rate of survival and reproduction for that specific environment. Have fun!

(Sam Lee salee4@students.d125.org)

Prompt #2; The Workings of a Disease

On pages 109-110, Dr. Moalem focuses on the purpose of sneezes, and why in particular we sneeze. According to Dr. Moalem, a sneeze "occurs when the body's self-defense system senses a foreign invader trying to get in through your nasal passages". By sneezing, the invasive pathogens are expelled with force away from the body. However, Dr. Moalem brings up the point that a person who has the common cold tends to sneeze more than if they weren't infected. Why would that be?

Further consideration lead to the discovery that the disease caused the victim to sneeze; therefore there was a purpose in doing so. By triggering the sneeze reflex, the cold virus can spread the infection through air to other potential victims.

Hence, sneezing, one of the most common symptoms of an infectious disease, is the product of host manipulation. What other, if any, symptoms do people infected with the common cold display, and how would the mechanism expressed specefically aid in the virus/bacteria in surviving and reproducing? Focus on symptoms related to the common-cold only.

Prompt 2-Males in Peacetime and Girls in Wartime

On pages 179-180, Dr. Moalem discusses that in the time after 9/11, there was a higher number of later term miscarriages, and most involved women who had male fetuses. In speculation, he stated that this may occur as an evolutionary response: with a lower percentage of males, and more females, it may be easier to repopulate an area after a disaster. The mother may sense something stressful in the environment, and terminate the baby as a result. This pattern has been seen after other natural disasters, like the Hanshin earthquake of 1995 in Kobe, Japan.
Genetically, how are  males and females different? Related to Big Idea 3, how could this miscarriage response be carried out by the body? How could the mother cause a miscarriage in a male fetus, and yet leave a female fetus unharmed? Is this truly a selective advantage? Does a large population of females and a lower population of males help cultivate a better environment for future generations? Why?

(Zachary Rane, zrane3@students.d125.org)

PROMPT 2: Genetics of Aging

On pages 184-185, Dr. Moalem discusses a devastating disease called progeria. This disease is characterized by accelerated aging where patients start experiencing wrinkling, hair loss, arthritis, and other degenerative diseases by the age of one and a half, which ultimately leads to premature death. Scientists in 2003 discovered the gene mutation that causes progeria. Big Idea 3: Living systems store, retrieve, transmit, and respond to information essential to life processes can be applied to this concept, because this issue discusses gene expression, and how DNA/possible mutations in the DNA affect cellular activities.

What is the name of the affected gene? What are the effects of the gene mutation that cause progeria? Think along the lines of gene expression and protein synthesis when answering this question. What does the discovery of this gene show about aging?

Describe the Hayflick effect and the role of telomeres. (Hint: There's a clever analogy on pg. 186!) How does telomerase alter the Hayflick effect and telomeres?

How are the life expectancies of a species and the external threats the species undergo related?

Mutations on the lamin A gene (aka LMNA) that cause progeria can lead to a wide variety of other diseases as well. Research another disease/disorder that results from LMNA mutations. Discuss what time of mutation(s) occured, how it affects the patient, and the symptoms of the disease.

(Michelle Liang, mliang4@students.d125.org)

Prompt 2 - Climate Change

In chapter 2, Dr. Moalem discusses the effect of the environment and rapid climate change on evolution and the reason we may develop certain diseases that help us survive in the present. The rapid climate change and ice ages made people with Type 1 Diabetes more likely to survive and reproduce because of their condition. This relates to Big Idea 1: The process of evolution drives the diversity and unity of life. The cold caused the development of Type 1 Diabetes, which during the time of the ice age was a selective advantage.

We know that Type 1 Diabetes resulted as a result of the rapid change to extremely cold weather, but is it possible that there are genetic diseases that result from an extreme weather shift to a hotter climate? Research and try to find a disease that either seems to like to a time period in history with a hotter climate, or try and find a disease that relates to a population that lives in an overall warmer climate than normal. Also, research if it is possible to develop different traits if a population moves from a climate on one end of the spectrum, say cold, to the other end, say hot. While doing research you may also come upon methods used to find these observations such as the tree rings discovered by Andrew Ellicott Douglass.

(Dana Morgan, Dmorgan4@students.d125.org)

Prompt #2 Big Idea #4: Toxicity of plants

In chapter 4, Dr. Moalem discusses the potentially dangerous fava beans that produce vicine and convincine (75 Moalem), which in turn produce free radicals that are harmful to our bodies.  He also goes on and mentions phytoestrogens (78 Moalem) that make an organism sterile, peppers (82 Moalem), plants in the nightshade family (81 Moalem), and various other plants that contain toxic substances.  The toxic defenses of the plants interact with our bodies when we eat them, illustrating big Idea 4.

However, theses toxic plants can sometimes become harmless when they are cooked.  Dr. Moalem uses the specific example of the fava beans again because when they are soaked or cooked, they lose their toxic properties.

There are many other species of plants that are harmful to humans.  Some can be cooked and are edible, but some are toxic whether cooked or not.  Find one common species of toxic plant that humans eat (one that Dr. Moalem does not mention).  What toxins does the plant produce?  Why are those chemicals harmful to humans?

Also explain why some plants can be cooked and become edible.  Explain what happens during the cooking process, at a molecular level.

(Katelyn Noronha, knoronh4@students.d125.org)

Prompt #2: The Long Term Effects of Phytoestrogen on Human Reproduction and Fertility

In Chapter 4, Dr. Moalem introduces the idea that plants develop defense mechanisms so they can survive and reproduce.  Many of the most powerful defense mechanisms present in plants exist at the chemical level.  One example Dr. Moalem shared concerns a group of plants including clover, sweet potato, and soy, which contains types of chemicals, called phytoestrogens.  If too much phytoestrogen is ingested, it may “wreak havoc on [animals’] reproductive capability” (pg 78).  In clover, if the plant has a bad year (due to environmental factors) then it increases the production of formononetin–a type of phytoestrogen–in turn, limiting the population of its predators for the next generation by sterilizing the possible parents.  (Big idea #1) Furthermore, Dr. Maolem notes that soy is rich in a phytoestrogen called genistein and indicates that there is growing concern of the long term effects of soy in our diet (pg 79).  Later on in the chapter, Dr. Maolem states that Asian women are reported to experience fewer problems with mid-life changes (menopause) due to the phytoestrogen in soy (pg 92).

Questions:  In Asia, where soy is a major part of diet, is there any evidence of decreased fertility in women?  Also, as humans ingest more soy, might there be increasing allergies or other adverse reactions to soy to protect our ability to reproduce (one of evolution’s driving factors)?

Rachel Chang (rchang4@students.d125.org)