5. Some bacterial enzymes are essential for virulence. Explain the stages needed to establish microbial infections. Classify bacterial toxins. Provide two examples and describe their mechanism of action on mammalian cells.
In: Biology
1. Can photo system 1 also absorb light and release electrons? How do the electrons be replaced?
2. What happens during non-cyclic electron flow? What product can be generated?
3. Summarize the events of the dark reaction. (All inputs and outputs)
In: Biology
Are most animals vertebrates or invertebrates?
How does bilateral symmetry differ from radial symmetry?
What is cephalization?
In: Biology
1) Discuss biocentrism. Explain its idea. What kinds of observation have led to the
development of this idea? How does this school of thought find support from quantum
physics? What do you think about this ancient idea that has been repackaged as new by
Robert Lanza? A link to an excellent reading about this idea is posted below:
http://discovermagazine.com/2009/may/01-the-biocentric-universe-life-creates-time-space-
cosmos
2) The mechanical philosophy, which arose from the scientific revolution, presents the
universe as a grand machine, one that operates blindly according to invariable laws. From
this mechanical view, the universe is devoid of teleology. As a machine runs according to
its rules, so does the universe. Darwin’s theory in 1859 expanded this non-teleological
conception of the cosmos to the living world. His theory of natural selection presented an
evolutionary process that is random and blind, the result of many accidents, some of
which were beneficial and, therefore, were preserved and have accumulated to drive the
change in form over time. This process gives the impression of an intentional, goal-
oriented process, but as natural selection is random and blind, any appearance of
teleology is an
illusion
. The science of abiogenesis, that studies the natural process
through which life has arisen, has operated since the 1920’s from the assumption that life,
as in its evolution, must also have arisen from a very random and high unlikely accident
of circumstances.
Discuss this non-teleological view of the universe, which has dominated physics and biology
for over 300 years. Do you agree with such a view? Do you see any lines of
evidence/observation that challenges the assumption that the universe operates blindly, that
life has arisen by accident, and that its evolution has come about through a strictly random
process? Regardless if you agree with a non-teleological view of the cosmos or not, support
your views with empirical data and observation.
3) Discuss the difference between technology and science. How are they related to each
other? How do they relate to the ‘Baconian vision’, put forth by Francis Bacon? Would
you say that we have achieved his vision, exactly as he envisioned it? Why or why not?
Finally, explain your position regarding the pros and cons of prioritizing applied research
over basic research. Deal with both sides of the argument. That is, argue why it is best to
prioritize applied over basic research. Then argue from the other side and make a case for
why it is better to prioritize basic research, or at least give equal funding to it. Finally,
explain your own personal position and why you hold it?
4) Discuss what you believe ‘consciousness’ is. Do all living organisms possess it? If not,
which do and which do not? From where do you think it arises? Finally, do you think we
can study understand the phenomenon of consciousness using the tools of reductionism
or do you think an epistemology of holism is needed?
5) In Erwin Schrodinger’s famous little book entitled ‘What is Life”, published in 1944,
Schrodinger looks at the phenomenon of life through the eyes of “a naïve physicist”. He
attempts to address the mystery of living organisms through appeal to physical and
chemical principles. This book has been said to have catalyzed what is now referred to as
the ‘molecular biology revolution’ that gained momentum in the 40’s and currently
dominates the life sciences. While acknowledging decades of productive reductionist
research in the life sciences there are those who argue that a shift to a more organismal
approach is now necessary if we are to truly answer Schrodinger’s question, “what is
life?”. This shift would means considering the organism as a whole without reducing it to
its constituent parts (aka organicism), the opposite of ‘reductionism’. My question to you
is whether you believe that a full explanation of life can be obtained by employing a
purely reductionist methodology? Why or why not?
6) We discussed quite a bit about the evolving role of mathematics in man’s endeavor to
explain the natural world. An eternal question remains: does mathematics exist as an
objectively ‘real’ language/symbolic scheme beyond man’s own mental construct? Or is
the whole of mathematics a contrivance of the human mind that man uses to describe the
universe? How do you personally see this debate? As always, explain your reasoning.
7) The following is a quote from a giant of 20th century biology, Carl Woese:
“Biology today is at a crossroads. The molecular paradigm, which so successfully guided
the discipline throughout most of the 20th century, is no longer a reliable guide. Its vision
of biology now realized,
the molecular paradigm has run its course. Biology,
therefore,
has a choice to make, between the comfortable path of continuing to follow molecular
biology's lead or the more invigorating one of seeking a new and inspiring vision of the
living world, one that addresses the major problems in biology that 20th century biology,
molecular biology, could not handle and, so, avoided. The former course, though highly
productive, is certain to turn biology into an engineering discipline. The latter holds the
promise of making biology an even more fundamental science, one that, along with
physics, probes and defines the nature of reality. This is a choice between a biology that
solely does society's bidding and a biology that is society's teacher.”
Quoted from
A New Biology for a New Century, 2004
Discuss this quote and your thoughts on the matter. Do you agree with Carl Woese? Has
biology become strictly an engineering discipline? If so, is there anything wrong with such
a direction? Do you think biology, as he suggests, has the potential to become a
fundamental science like physics? If so, how? Again, these questions are meant to be
suggestive to get you thinking about this topic. Feel free to discuss in your own way
In: Biology
3. explain the location and role of the endodermis in regulating the movement of substances into and out of the root's vascular cylinder. You musr use, but are not limited to the following: Casparian strip, plasma membrane, endodermis, symplastic, apoplastic.
In: Biology
An alien species was found with the following characteristics Flat feet dominant over round feet A vs a 10 toes dominant to 15 toes B vs b Curved ears dominant to straight ears C vs c A flat footed, curved eared alien with 10 toes was crossed with a round footed, 15 toed, straight eared individual and produced the following offspring
Flat, curved, 10 toes 588
Round, straight, 15 toes 599
Flat, 15 toes, straight 165
Flat 15 toes, curved 159
Round, 10 toes, curved 145
Round, 10 toes, straight 163
Flat, straight, 10 toes 15
Round, curved, 10 toes 23
What gene is in the middle?
How far apart are the genes?
In: Biology
You are interested in mapping the genetic distance between two phage genes. You know from your genetics course that relative gene distance in both bacteria and eukaryotes can be determined by finding the recombination frequency of the two genes.
You infect a bacterial cell with two phages (h+r+ and hr) and you plate the progeny phages onto a bacterial lawn containing both strains of bacteria susceptible to the h mutant phenotype.
a) Describe all the possible plaque phenotypes you would see and the genotypes associated with each.
b) Which two phenotypes are the most abundant?
c) If the two most abundant plaque phenotypes together total 140 out of 200 plaques, what is the genetic distance between these two genes in map units?
d) What would happen if the double mutant phage (hr) had failed to coinfect the bacterial cell? Would your plate look the same? Why or why not?
In: Biology
What are "cell formation cycles" and why would one want to use them?
In: Biology
In: Biology
Bacterial Endotoxin Limit (EL) is defined as EL=K/m, where K=5 Endotoxin Units (EU) kg of the body weight or 5 EU/kg/hr;m= maximun bolus dose of a product, and the average human body weight is 70kg.The maximun Valid Dilution (MVD) of a product is equal to (EL x Concentration of the product)/sensivity of the lysate
Find the EL for a product whose maximun pediatric dose is 4 mg/ml/kg and concentration is 20mg/ml. Expressthe EL in EU/ml and EU/mg
If the sensivitty of the lysate is EU/ml, the Endotoxin soecification per monograph is EU/mg, the maximun bolus dose is 1ug/kg/min and the concentration is 0.2mg/ml.CAn the monograph specification be used as the Endotoxin limit? Explain
Calculate the MVD based on problem #2
In: Biology
In: Biology
Explain the way of action of antibiotics known as
aminoglycosides, tetracyclines and macrolides. Give detailed
answer.
In: Biology
Insulin-like growth factor 2 receptor (Igf2r) gene is expressed exclusively from the maternal allele on chromosome 17 due to
A. differential methylation of an Igf2r intron.
B. differential expression of an antisense RNA transcript.
C. transposition of the maternal copy of Igf2r.
D. methylation of an imprinting control region.
In: Biology
In: Biology
18. Entamoeba histolytica is the causative organism in amoebic
dysentery. This organism is a(n)
Protozoan
Bacterium
Fungus
Virus
20. Antibiotic-induced diarrhea is most often caused by an
overgrowth of this specific bacterium:
Clostridium difficile
Clostridium perfringens
Candida albicans
Yersinia pestis
22. Acute glomerulonephritis is a late-developing consequence of
which of the following diseases?
Streptococcal pharyngitis (strep
throat)
Influenza
Rhinosinusitis
Pneumonia
31. The opportunistic pathogen often responsible for causing
necrotizing fasciitis (also known as the "flesh-eating bacteria")
in healthy young adults is called:
Staphylococcus epidermis
Streptococcus pyogenes
Bacillus subtilis
Streptococcus pneumoniae
In: Biology