Upload
peter-chau
View
221
Download
0
Embed Size (px)
Citation preview
8/2/2019 AP Bio Book Assignment
1/5
Michael Chau
AP Biology Book Assignment:
The Secret Life of Germs by Philip Tierno
Chapter 1: Seeds of Disease, Seeds of Life
I knew from prior knowledge that hospitals were grounds for contracting disease from
contaminated hospital staff, but I did not know that there was a particular name for this
transaction. I also thought that these nosocomial infections were rare, but apparently this is notthe case. It seems that cleanliness is lacking in hospitals so much that nosocomial infections
become fatal for patients. On the other hand, I did not realize the importance of germs in modern
life. Obviously, bacteria help aid in the digestive process but they are also used cosmetics and
paitns as well as food that require yeast. I do agree with the author that society should make a
more conscious decision to improve cleanliness which would ultimately improve public health.
As the author stated, we cannot live in a world free of germs, but we can learn to maintain a
healthy balance with them.
Chapter 2: How We Make Each Other Sick
What shocked me the most in this chapter was when samples were taken from germ hotspots in
New York. I wasnt surprised by the fact that there were many germs in New York, but by the
types of germs that were found. I was repulsed when the author found germs that are found in
feces on not just seats but also headsets in a movie theater. Another germ that was discovered in
New York City was a flesh-eating bacterium which I knew was relatively rare despite it being
found on a public phone. The author does stress the importance of washing your hands but I
believe it is important to take it a step further and have commonly used objects sanitized as well.
I was also intrigued by how regular hand soap actually worked in cleansing our hands. I was
interested because I knew how antibacterial soap worked, but not how regular hand soap gets rid
of germs. I also thought it was important to use hot water (almost to the point of scalding), but itis not necessary as soap loosens particles and removing them when washed. The last thing that I
thought was humorous or interesting was the author ironically condoning littering as he states,
If there is no waste receptacle near the door, drop the paper towel on the floor, [p.29].
Chapter 3: The Germ Domain
The author stated the origins of life, basic compounds, as well as our solar system. A component
of DNA or RNA, which are foundations for life, being a sugar molecule was found in gas/dust
clouds near the center of the Milky Way so life-forms, including us, are made up of substances
that also created planets. It gives me the sense of humans being a sort of cosmic being. I also
found out that germs were responsible for creating the ozone layer that we depend upon for
creating an inhabitable planet. I had assumed that the atmosphere and ozone layer created in thesame way the rest of the earth was created. I was interested by the dual-nature of germs
especially Streptococcus pneumonia. We could live with it in a mutualistic relationship or a
parasitic relationship if it made its way into our lungs. I found this interesting because before
reading, I thought that there were good or harmless germs and there were harmful germs and it
did not occur to me that germs can be both.
8/2/2019 AP Bio Book Assignment
2/5
Chapter 4: The Germ Factory
I was mainly interested in the section on the smells of human flora particularly bad breath as I
have seen commercials for a product called the Orabrush. The commercial talked about halitosis
and that the main cause of bad breath was bacteria in the back of the tongue which the Orabrush
removes. The book confirms this as well stating that a heavy concentration of anaerobic bacteria
on the back of the tongue will produce malodors. I also question the authors solution to foot
odor caused by normal skin flora. He says that foot odor can occur when wearing dark shades of
socks and that wearing light-colored all-cotton socks will remediate the odor. What is the point
of switching socks if most people wear shoes which will give the same dark environment as
dark-colored socks? I found the protective response strategies that the author provides very
helpful, though some of them are rather unusual such as one regarding defecation. He offers
suggestions to relieve others of bad breath such as gargling a hydrogen peroxide solution along
with more traditional remedies like chewing parsley. These kinds of tips are helpful as bad breath
is rather common.
Chapter 5: The Enemy Within
The line, With so much exposure to potentially dangerous germs, why dont people continually
fall ill with one ailment after another? [p.62] struck a chord with me. I had pondered the same
question and hypothesized that our immune system deals with pathogens before we feel
symptoms or that the pathogen needs to be numerous in order to cause damage. This correlates
with the idea that some people have stronger immune systems as well as memory cells which cut
the bodys response time to pathogens. The author says that over evolutionary time, pathogenswill become less lethal and more mutualistic in order to live longer. I am not sure if I agree with
this especially since pathogens are changing yet are still dangerous. One example is the influenza
virus which has many strains of the virus so repeated vaccinations are necessary. Also the
emergence of antibiotic resistant germs such as MRSA has shown to be fatal. One of my favorite
parts was learning about how the immune system combatted pathogens because it greatlyimproved my knowledge on the immune system in a scientific perspective. I knew about
lymphocytes and T cells, but I did not know about NK cells. I was surprised that they kill tumor
cells and it made me wonder if they could be implemented in a cure for cancer.
Chapter 6: Person to Person
This chapter offered practical tips for keeping clean in our daily lives. One qualm I do have is
that the author says that clothes are best sun-dried because the UV rays can kill any germs left
from washing. Earlier in the book, he mentioned that germs were resistant to radiation. Perhaps
this resistance applied to certain germs or that the authors clothe washing procedure weakens
the germs and UV radiation is able to finish them off. The author brings up an interesting point
about money. Money is circulated every day and most likely become fomites due to contact withall sorts of people. Money usually doesnt leave circulation either so they continually become
ridden with germs. It would not be surprising if money become the source for disease spreading.
The author also told the story about Typhoid Mary whom I read about in another book. Her case
confused me because after she learned that she was a carrier of typhoid fever, she was forced to
quit her job as a cook and worked in a laundry. For some reason, she went back to being a cook
despite knowing she would inevitably end up infecting others. I wonder if she realized that she
was the cause of the death for three people.
8/2/2019 AP Bio Book Assignment
3/5
Chapter 7: Common Ground
Reading this chapter was the first time I have heard of a bacterium that thrives in refrigerator
temperatures.Listeria moncytogenes is the exception to the principle that germs prefer warm and
humid environments which is why refrigerators limit and reduce growth of germs. Apparently,
this bacterium can survive in warmer temperatures as well as they can survive the pasteurization
process of foods. I was interested when the author said that freezing shellfish would kill germs or
some of them on the shellfish. This procedure is also used for sushi-grade fish. Particularly, I
was wondering how they die from low temperatures rather than stay dormant. It could be similar
to why human cryogenics does not work as ice crystals form and tear tissues and cells. The
Protective Response Strategies that were offered were rather obvious and stemmed from
common sense but two of them peaked my interest. I thought it was rather strange to soak
produce in a solution that contained hydrogen peroxide in order to cleanse them of germs as it
could kill you if consumed. I also didnt know some beverages other than milk needed
pasteurizing such as apple cider and orange juice.
Chapter 8: In Thin Air
I was fascinated by the section on allergies partially because I suffer from hay fever during
spring. This allergy, though, pales in comparison to fatal allergic reactions or asthma. I agree
with the author that cleanliness does have a positive effect on allergies. He disagrees with
scientists who say that over-cleaning will expose children to less allergens so when they do, they
suffer from asthma. They support this with the fact that Third World countries have lower
asthma rates than the U.S. This is probably because people die from other diseases before
developing asthma. Also, I have been exposed to pollen many times but yet still have allergies.
Then again, it is possible for allergies to develop in people who never had the allergy in later
years. It could be because they havent been exposed to it for a period of time. There is also
allergen immunotherapy where the body receives higher doses of the allergen in order to become
immune. I still agree with the author that cleanliness is far too important to give up especiallysince even the cleanest homes are not sterile.
Chapter 9: On the Wing and on Eight Little Legs
The author mentions how birds are sensitive to their environment and how they act as an
indicator for disturbances. This reminds me of a study on birds and how they were affected by
the pesticide, DDT. DDT was found in high levels in birds because when DDT was sprayed on a
particular species of trees, insects and worms fed on its leaves who became prey for birds. The
birds would then accumulate DDT from each prey and eventually die. An interesting tidbit I
learned was that mosquitoes can extend their life in order to find a suitable place for their young
and even survive through mild winters if they need to. I liked learning about malaria because I
wanted to extend my knowledge on it. For example, I knew about how sickle-cells was effectiveagainst malaria because they had a shorter life span than normal red blood cells and died, taking
the malaria pathogen, which reproduces inside it, along with it. I didnt know that sickling
depleted potassium in red blood cells preventing the reproduction of the malaria pathogen.
8/2/2019 AP Bio Book Assignment
4/5
Chapter 10: Not the Usual Suspect
Surprisingly, I found many connections between this book and my AP Psychology books. I was
intrigued by the story of Dr. Barry Marshall who ingested a certain bacterium that caused ulcers
to prove that ulcers were caused by bacteria. This same story was recalled in the book Phantoms
in the Brain by V.S. Ramachandran. I was enlightened on the fact that germs could cause cancer
and heart disease, but I had learned before that HPV was associated with cervical cancer. I was
astonished at the number of viruses that caused non-communicable diseases. Examples include a
herpes virus causing cancer in the throat and several strains of chlamydia caused heart disease
and cervical cancer. Even more shocking was that viruses could also be responsible for mental
illnesses and disorders.
Chapter 11: The Germ Revolt
Situations where patients stop taking antibiotics when their symptoms clear, rather than
completing the prescription, remind me of how manic-depressive illness patients have a hard
time staying on drugs when they feel normal. Recurring manic-depressive attacks become worse
similar to antibiotic resistant bacteria in that the situation from not finishing a prescriptionbecomes worse. I agree with the authors thoughts on germicides partly because of accurate
research as well as flawed studies. For example, triclosan was tested on antibiotic-resistant
bacteria and susceptible bacteria and shown to be effective against both and doesnt create
resistance in germs like antibiotics. A study on triclosan was made on unnatural strains of germs
and failed to cover the germicides effects on other types of germs. This has led me to believe
that germicides should be used along with soap and water, and antibiotics should be used
sparingly.
Chapter 12: Germ Warfare and Terrorism
I was shocked at the number of potential biological weapons which totaled to 17. I only knew
three of them which were anthrax, smallpox, and cholera. Apparently, these dangerous weaponscan be found in nature and therefore plentiful. Thankfully, I believe that biological and chemical
weapons are banned under Geneva Conventions. Despite this, there was the recent anthrax letter
scare. I disagree with the author when he states that the incubation period of biological agents
can be a plus. He argues this point by saying how too long an incubation period would diffuse
the impact that terrorists hope to achieve. Biological weapons are going to cause damage
anyways whether the incubation period is long or short so I dont think morale for terrorists is
much of a problem. Victims usually die soon after experiencing symptoms anyway so long
incubation periods wouldnt affect the number of deaths.
Chapter 13: Germs for Life
It is pointed out that much money is wasted on infectious disease mainly by AIDS, food-borne
illnesses, and non-socomial infections. These infections can easily be prevented if proper
precautions are set and therefore save a lot of money. I agree with the authors point of view that
education is the first step to living in a healthier world. It is important to know that good hygiene
will keep yourself and others safe. I found the use of probiotics to be interesting and may
possibly become a large part of treating infections. They can even help with problems not caused
by germs such as high blood pressure or carcinogens. Other interesting innovations that I found
8/2/2019 AP Bio Book Assignment
5/5
were antisense drugs, decoys and blockers, multi-headed antibiotics, and genetic engineering.
Despite the length of the fight against germs and reduction of magic bullets, we are still able to
produce effective cures and treatments for diseases.