All of the above points are valid for fossils' contributions in understanding the process of evolution. They allow us to study the ancestry, we can see the homologous organs or structures, if fossils are well-preserved; different fossils can lead us to follow the cycles of the changes that occurred during macroevolutions, and fossils can be used to study different populations which had different body structures for surviving in different environmental conditions.
Answer:
<em>a. What is the significance of the rainfall? </em>These bacteria resist desiccation, and its dispersion is favored by winds. A decrease in rainfall means a dryer environment, which the bacteria can resist and makes it easier for the cell to be carried somewhere else by winds.
<em>b. The etiologic agent of the disease is </em><em>Coxiella burnetii</em>
<em>c. This is an example of</em> a zoonosis
Explanation:
Q fiber Pneumonia is a zoonosis world-widely distributed and of global importance, which etiologic agent is <em>Coxiella bunetti</em><em>.</em>
- Zoonosis: Referred to as the infectious diseases that are naturally transmitted from animals to human beings. Among zoonotic pathogens, there are bacteria, viruses, or parasites. They propagate by direct contact, water, and wind, among others. These diseases represent a global importance problem due to the close ties with animals. Zoonotic diseases increase even more as human being keeps dispersing and invading natural wild environments to raise cattle and farm, among other activities.
- The etiologic agent is the element that propitiates the origin and evolution of a disease. Many bacteria and viruses might be considered to be one of the most common etiological agents.
Populations in contact with goats, sheep, and cattle, use to have a positive result for antibodies against <em>Coxiella burnetii</em>. This bacteria is transmitted to humans orally and by inhalation. The microorganisms resist extreme conditions and are highly infectious. The inhalation of only one cell can produce an important infection in the host. It resists desiccation and any other environmental degradation. They can persist for several months and be transported by winds to farther places. This makes it even more difficult to determine the epidemiologic origin.
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Answer:
Independent variable: Adding/not adding soil.
Dependent variables: Does the plant grow? Amount of leaves, plant length.
Controlled variables: Type of plant used, amount of sunlight received, pot used for plant, amount of water given, temperature of soil, etc.
Explanation:
Independent variable: The thing that you want to change. To see if plants need soil to grow, you would need to either add or remove soil altogether.
Dependent variables: The thing that is being measured. By adding your independent variable, you should be able to answer certain questions.
Controlled variables: Things you want to keep the same for each experimental group. For example, if you used different plants, your results could be affected negatively as some plants might rely on soil less than others/grow at a slower or faster pace.