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Case study #4 Plasmodium falciparum is the most virulent causative agent of malaria. This parasite has a trophozoite form that must undergo a life cycle within the gut of the female Anopheles mosquito to be naturally transmitted to the next host. The parasite also has separate trophozoite forms in the liver and blood of humans. If the malaria parasite is introduced into a pregnant woman, it can cross the placental barrier and infect the developing fetus. People at increased risk for malaria infection are children under 5 years old, pregnant women, and people with AIDS (active HIV infection).   What kind of organism is P. falciparum?

Case study #5 Listeria monocytogenes is a chemoheterotrophic facultative anaerobic Gram-positive bacterium that can act as a human pathogen or as a saprobe, depending on its environment. This bacillus-shaped cell is motile, moving with peritrichous flagella. This bacterium has a high salt tolerance and can multiply readily at 4 oC (refrigerator temperatures). L. monocytogenes is part of the normal gut microbiota of many farm animals, including cows. Deli meats, hot dogs, and unpasteurized cheese and milk are likely sources of this pathogen. Many antibiotics can be used to treat infection with L. monocytogenes, including drugs that target peptidoglycan biosynthesis, the small ribosomal subunit of bacteria, and folic acid biosynthesis.   While L. monocytogenes replicates at 4 oC, it cannot replicate on foods that are frozen (0 oC). This is because

A teacher has contracted influenza virus from a student one day before the student began exhibiting symptoms. The student represents what kind of carrier?

Case study #3 Dental caries (dental decay) is the result of solubilization (dissolving) of tooth enamel by acid. The microbes associated with cavities, usually the Gram-positive Streptococcus mutans and Lactobacillus species living in biofilms as plaque, produce organic acids as the waste product of a specific metabolic pathway. Regular tooth brushing and chewing gum after meals, which increases saliva production, and are the two leading methods that can be preformed daily to prevent tooth decay.   What term(s) in the case study description supports your answer for the metabolic pathway used by S. mutans in plaque (what term(s) supports your answer to the previous question)? 

NOx emissions from the degradation of nitrogen fertilizer include:

Use the figure of Cytotoxic T Lymphocyte activation above to match the proper term to the numbered/color-coded components.  

The radiation (which includes light) that is intercepted by the earth’s magnetic field and ozone (O3)?

Case study #6 Clostridium botulinum is the causative agent of botulism. This Gram-positive, anaerobic bacillus is commonly found on plants, in soil and water, and in the intestinal tract of some animals. The main virulence factor of C. botulinum is botulism toxin, which is a protein neurotoxin that causes muscle paralysis. Death results from paralysis of respiratory muscles. Genetic analysis has led to the understanding that C. botulinum has acquired its toxin genes from lysogenic bacteriophages. Adults who ingest C. botulinum spores alone generally do not become ill. However, adult botulism will result after ingestion of food containing botulinum toxin. Boiling and common chemical treatments used for water denatures botulism toxin. Infantile botulism, rather, results after children under the age of one ingest foods, such as honey, which contains C. botulinum spores but no botulinum toxin. Once inside the infant gut, these spores germinate and botulism toxin is produced after colonization. Treatment for botulism requires injections of botulinum antitoxin, pre-made antibodies that are administered to the patient as quickly as possible.   Botulinum toxin can be best described as a(n)

List two factors that have led to a decline in fertility in the post-WW2 era. Provide a brief economic explanation of how each led to a decline in fertility.

Expert chess players outperform novices in terms of recalling piece location for both random and in-play (real) boards.