write a 2 to to three-page essay about National Geographic Society and its mission and main actions.

Renal physiology (select the CORRECT statement)

During the golden age of antibiotic discovery, many new antibiotics were isolated from the soil. Recent studies have found that soil bacteria are naturally resistant to most antibotics. Some of the soil bacteria may even use antibiotics as a nutrient source. Antibiotics must kill a broad spectrum of bacteria while being absorbed harmlessly by the body. Most antibiotics were developed based on Ehrlich "magic bullet" paradigm which is suited to testing antibiotic efficacy in a lab. However, infections are more complex than a pure culture on media in a petri plate. Antibiotic resistance conjures up the pre-antibiotic era of medicine in the early 20th century. The emergence of a plasmid mediated resistance to carbopenems, a last-line drug against a variety of bacteria was alarming to public health workers. Antibiotics may cause collateral damage like a C. diff infection that leads to colitis.

5. Why is a bacterial infection that involves a biofilm harder to control with antibiotics than an infection which does not involve a biofilm?

6. Explain how taking antibiotics would cause the bacteria Clostridium difficle, which is part of the healthy colon microbiome, to become pathogenic?

7. How do bacteria resist antibiotics?

Bacteria also develop resistance to biocides. Traditional cleaning methods for equipment may have limitations. For example, patients who recieve a bed used by a prior patient with a bacterial infection are at an increased risk for being colonized and infected by that same bacteria. In addition, bacteria in a healthcare setting are exposed to disinfection which selects for the resistant members of that bacterial population. No-touch methods of disinfection, i.e. uv light or hydrogen peroxide vapor, of equipment may be an improvement. https://www.ncbi.nlm.nih.gov/pubmed/29214175# (Links to an external site.)Links to an external site..

8. Are biofilms a concern when disinfecting equipment? Why?

During the Flint, MI water crises as levels of chlorine fell in the drinking water cases of Legionnaires' disease increased. Legionnaires' disease is a water borne infectious disease caused by Legionella. One study reported that for every drop in cholorine concentration of mg/L of river water the odds of a reported case of Legionnaire's disease increased by 80%, thus establishing not causation but association. Some argued that Legionella is tolerant of chlorine, espceillay when it grows in biofilms and that the temperature difference between lake and river water accounts for the increase in Legionella infections. The recommended level of chlorine to treat water for drinking is 0.2-0.5 mg/L.

doi:10.1126/science.aat2210 Was Flint’s deadly Legionnaires’ epidemic caused by low chlorine levels in the water supply? David Shult (Links to an external site.)Links to an external site.z

Was Flint’s deadly Legionnaires’ epidemic caused by low chlorine levels in the water supply?

9. What effect would increasing the concentration of chlorine to 1.4 mg/L have had on the people who drink Flint water?

10. What happens to the water pipes when chlorine levels are increased to control bacteria? Could these uninteded consequences increase bacterial growth?

Renal physiology (select the INCORRECT statement)

4. (10 pts) Hemoglobin S or sickle cell hemoglobin forms fibers in red blood cells because
of a Glu→Val mutation on the surface of the protein. The mutated residue interacts
with Leu and Phe residues located on the surface of a different protein molecule. This
interaction drives the formation of the fibers. Explain why higher concentrations are needed to form fibers at lower temperatures.

One very diverse group of eukaryotic microbes are protozoa. All protozoa are eukaryotic, unicellular and lack cell walls. Many protozoan are chemoheterotrophs, getting energy and carbon from other organsims. Two groups of protozoans that are photosynthetic are dinoflagellates and euglenoids. Protozoans are divided into six groups: Parabasalids have a Golgi like organelles, a parabasl body, and lack mitochondria. Examples: are 1. Trichonympha which live in the guts of termites and digest cellulose into glucose. 2. Trichomonas which lives in the acidic environment of the human vagina, if the pH is increased, it can proliferate and cause inflammation which might lead to sterility. Diplomonadida lack mitochondria and have two rudimentary mitochondria called mitosomes, two equal size nuclei and multiple flagella. An example of this type of protozoan found in well water or lake water if Giardia, the ingestion of cysts leads to a GI infection characterized by flatulence and diarrhea. This protozon looks owl like in a light microscope because of the two nuclei. Euglenoza Euglenids:lack cell walls, have flagella, are chemoheterotrophic phagocytes in the dark, and have several features unique to euglenids. For one they store energy in a polysaccharide paramylon. They may move by a squirming motion called euglenoid movement. They have a protein pellicle under thier plasma membrane to give the cell shape. Most have a "red eyespot" that helps with phototaxis. Kinetoplastids have a single large mitochondria that contain a kinetoplast Two notable pathogens in this group are Trypanosoma and Leishmania. Alveolates have small membrane bound cavities beneath the plasma membrane called alveoli. In addition, alveolates have tubular mitochondria cristae. There are three subgroups. Ciliates have cilia for motility or to move water past the cell surface. Ciliates are chemoheterotrophic and have two nuclei. The only pathogenic ciliate is Balantidium. Paramecium is a well known pond dweller used to study regeneration. Apicomplexans are chemoheterotrophic animal pathogens. They contain apices which are organelles that contain enzymes that allow the protozoan to penetrate host cells. Three examples of apicomplexans are Plasmodium, cryptosporidium and Toxoplasma.

12. According to CDC toxoplasmosis is a neglected parasitic disease. Cats play an significant role in transmitting the protozoan because cats become infected by eating infected rodents or birds. An infected kitten may shed as many as a million cysts in thier feces for up to 3 weeks after infection. Humans may become infected by changing cat litter boxes or gardening without gloves. Suggest at least two ways a person may prevent infection based on this information. You may also visit the CDC websitehttps://www.cdc.gov/parasites/toxoplasmosis/gen_info/pregnant.html (Links to an external site.)Links to an external site..

Bateman’s Principle is based on the concept of Anisogamy. Explain Bateman’s Principle and Anisogamy and explain how this relates to Sexual Selection. Does Bateman’s Principle predict that animals should exhibit a Polygamous Mating System? And, if so, why does Monogamy exist?

“Nothing in Biology makes sense except in the light of evolution”. At the core of all biology is Darwin’s Theory of Natural Selection. Explain this theory (in detail), in relation to behavior.

Animals belonging to Acoela are protostomes with one body opening

True

False

answer the following questions regarding quorum sensing.

1) Definition in case of bacterial cells

2) Its role in formation of biofilm and its significance in environmental engineering bioprocesses

3) What kind of signaling molecule of aerobic bacteria can you use to control the biofilms in an environmental engineering system and describe its control mechanism.

How can I quantify visual cortex development of blind rats and normal rats?

What variable do I have to measure for that and by which stain method?

Homeostasis is the process of maintaining a constant internal environment. However average body weight has been increasing worldwide, seemingly in contrast to the concept of homeostasis. Address the following issues using the textbook and optional outside sources (include citations). Opinions need to be supported by scientific facts.

1. What is the evidence that genetic factors influence body weight? What is the evidence that environmental factors contribute to body weight?
2. What are the benefits and risks of higher body weights?
3. What might account for the increase in body weight in the modern world?
4. What is a healthy body weight? How might it be maintained? Justify your answer.

What happens to the concentration of H⁺ in the intermembrane space and the matrix as electrons move down the ETC?

1

Variation in what part of the pathway would affect the production of each of the melanin pigments? Describe the consequences of mutations in different parts of the pathway and its effects on the two melanin pigments.

2

Propose a mechanism by which the C-T nucleotide change in TYRP1 gene may have caused the blond hair trait.

3

Using the Hardy-Weinberg equilibrium:
a. What are the observed genotype frequencies in the Solomon Islands?
b. Calculate the blond hair allele frequency and the dark hair frequency in the Solomon Islands and worldwide.

c. If we assume that the population follows Hardy-Weinberg assumptions, what is the expected frequency of heterozygous carriers in both populations?

4

How do you think the gene for blond hair was introduced to the islands?