Exam 15: The Evolution of Microbial Life

Which gas began to increase in the atmosphere as a result of photosynthesis by autotrophic prokaryotes approximately 2.7 billion years ago?

Under ideal conditions, prokaryotes are capable of reproducing at a(n)________ rate.

Which group of prokaryotes aids digestion in cattle, deer, and other animals that obtain nutrition from cellulose?

Which group of organisms is most closely related to plants?

All of the species in the list below are seaweeds. Which is the EXCEPTION?

Large, diverse, multicellular organisms first appeared in the fossil record approximately ________ million years ago during the ________.

Recent scientific studies of the impact of microbiota on the amount of fat versus lean body mass (i.e., body composition)are described in your text. How do those studies illustrate the importance of microbiota communities in our bodies?

What accounts for the similarity between seaweeds and plants?

Which reasoning is a plausible explanation for why it may be difficult to treat infections that arise from tooth decay?

Scenario Malaria is a disease caused by parasitic protists in the genus Plasmodium. The parasite is transmitted to humans by female Anopheles mosquitoes. The Plasmodium parasite feeds on human red blood cells, eventually destroying them. Humans infected with malaria can exhibit many symptoms. Depending on the severity of the infection, these can range from fever, chills, sweating, and headaches to anemia and kidney failure. Ultimately, malaria can result in death. However, if time and money permit, once a person is infected, they can be treated with different antimalarial drugs. Two commonly used drugs are artemisinin and quinine. In addition, one way to prevent the spread of malaria is to apply pesticides to treat areas with Anopheles mosquitoes. The National Malaria Eradication Program began work in 1947 with the goal of eliminating malaria from the southern United States. In 1947, 15,000 cases of malaria were reported nationwide. By 1950, only 2,000 cases were reported, and by 1951, malaria was considered eradicated from the United States. Today, the disease is most common in Africa and South America, two continents that are highly impoverished. About one million people die from malaria every year, many of them children. In Africa, it is estimated that one in every five childhood deaths is due to malaria. -A vector is an organism that transfers a pathogen to a host. In the case of malaria, the vector(s)is (are)________.

The plasmodium of a plasmodial slime mold can grow in order to enlarge the organism's surface area and therefore potentially obtain more nutrients. This is an example of ________.

Scenario Malaria is a disease caused by parasitic protists in the genus Plasmodium. The parasite is transmitted to humans by female Anopheles mosquitoes. The Plasmodium parasite feeds on human red blood cells, eventually destroying them. Humans infected with malaria can exhibit many symptoms. Depending on the severity of the infection, these can range from fever, chills, sweating, and headaches to anemia and kidney failure. Ultimately, malaria can result in death. However, if time and money permit, once a person is infected, they can be treated with different antimalarial drugs. Two commonly used drugs are artemisinin and quinine. In addition, one way to prevent the spread of malaria is to apply pesticides to treat areas with Anopheles mosquitoes. The National Malaria Eradication Program began work in 1947 with the goal of eliminating malaria from the southern United States. In 1947, 15,000 cases of malaria were reported nationwide. By 1950, only 2,000 cases were reported, and by 1951, malaria was considered eradicated from the United States. Today, the disease is most common in Africa and South America, two continents that are highly impoverished. About one million people die from malaria every year, many of them children. In Africa, it is estimated that one in every five childhood deaths is due to malaria. -If an area infested with female Anopheles mosquitoes is treated with pesticides, and these mosquitos live, continue to breed, and continue to spread malaria, what can we conclude?

Which organism is a colonial form of green algae?

Ribosomes can perform some of the functions of both ________ and ________.

Scenario Endotoxins are commonly found in the air, both inside and outside our homes. These "air endotoxins" can come from sources that include house dust mites, agricultural and industrial dust, and dust from indoor pets. Air endotoxins are typically found in low amounts, but production of them can increase dramatically under specific environmental conditions such as dampness, mold, and sewage. Many scientific studies have been conducted investigating possible links between indoor endotoxin levels and asthma, chronic bronchitis, and other upper respiratory diseases. Interestingly, some studies have found positive correlations between indoor endotoxin exposure and severity of some of these diseases while other studies have suggested that some air endotoxin exposure can actually decrease the risk of developing asthma in children. Additionally, data suggest that industrial workers who are exposed to endotoxins in the air can develop irreversible lung damage. In 2005, Hurricane Katrina devastated the eastern coastline of the United States. The state of Louisiana, and in particular the city of New Orleans, experienced tragic loss of human life and homes due to the failure of the levee system. Intense flooding destroyed homes and created severe exposure to wet, moldy surfaces. At that time there were no regulations in existence on the amount of exposure that individuals should have to air endotoxins. Scientists from the Natural Resources Defense Council who wanted to determine if endotoxin levels had risen in New Orleans conducted tests across 12 outdoor areas, 9 of which had been significantly flooded while the other 3 were less affected. Two indoor areas were also sampled for endotoxin levels. No significant differences were found in endotoxin levels between the flooded and non-flooded areas or between the indoor and outdoor areas. However, a limited number of samples were collected, and they were taken after a recent dry spell. Endotoxin levels at all sites were found to be higher than national average levels but were lower than levels typically associated with long-term changes in lung function. -What is a logical conclusion to draw from this study?

Scenario Malaria is a disease caused by parasitic protists in the genus Plasmodium. The parasite is transmitted to humans by female Anopheles mosquitoes. The Plasmodium parasite feeds on human red blood cells, eventually destroying them. Humans infected with malaria can exhibit many symptoms. Depending on the severity of the infection, these can range from fever, chills, sweating, and headaches to anemia and kidney failure. Ultimately, malaria can result in death. However, if time and money permit, once a person is infected, they can be treated with different antimalarial drugs. Two commonly used drugs are artemisinin and quinine. In addition, one way to prevent the spread of malaria is to apply pesticides to treat areas with Anopheles mosquitoes. The National Malaria Eradication Program began work in 1947 with the goal of eliminating malaria from the southern United States. In 1947, 15,000 cases of malaria were reported nationwide. By 1950, only 2,000 cases were reported, and by 1951, malaria was considered eradicated from the United States. Today, the disease is most common in Africa and South America, two continents that are highly impoverished. About one million people die from malaria every year, many of them children. In Africa, it is estimated that one in every five childhood deaths is due to malaria. -Plasmodium illustrate feeding characteristics of a(n)________.

In Yellowstone National Park, hot springs can reach temperatures of 205°F (96°C). Despite these high temperatures, Aquifex bacteria flourish. How might one best classify Aquifex bacteria?

All organisms that photosynthesize fit into which nutritional category?

Eukaryotes that are not fungi, animals, or plants are classified in a "catch-all" category called ________.

What kind of prokaryotes are shown in the figure?