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27 Jan 2018

Why is building a phylogeny based on symplesiomorphies considered a bad idea? In your answer, define a symplesiomorphy and also give an example using real organisms: describe several species and at least one symplesiomorphy that applies to them, and then describe what happens when you use that symplesiomorphy to try to understand phylogenetic relationships among the species.

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teacherrecoLv10

27 Jul 2023

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Sixta KovacekLv2

29 Jan 2018

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Related questions

Of the following sets of species, state which species definition (morphological, phylogenetic, or biological) best applies

a. Species boundaries in many tiny organisms, such as Oligotrich ciliates that live in the ocean, are determined using features that are visible under a light microscope.

b. Two wild relatives of lettuce, Lactuca canadensis and Lactuca graminifolia, produce flowers at different times â L. canadensisflowers in summer and L. graminifolia flowers in early spring.

c. As their names suggest, spring field crickets (Gryllus veletis) mature and become reproductively active in the spring, while fall field crickets (Gryllus pennsylvanicus) mature and reproduce in the fall.

d. Several closely-related (and very similar-looking) species of fungus in the genus Wallemia were identified using an evolutionary tree based on DNA sequences from several genes.

e. The breeding season for the red-legged frog (Rana aurora) occurs between January and March, while the breeding season of its close relative (Rana boylii) lasts from March through May.

f. Analysis of evolutionary relationships among several species of crayfish in the genus Pacifastacus were used to distinguish species from one another, and to identify species of possible conservation concern.

magentahamster225

An area has two different Anopheles species, both of which can vector Plasmodium, although Plasmodiumdevelops best and is transmitted best by species B. Species A is dominant because its larvae outcompete species B in the main shared breeding sites, small lakes and ponds. Therefore the population of B is currently small. The small lakes and ponds are also the source for the main food source in the region, fish, grown in fish farms. There is grazing land, but other than chickens, the local population does not have livestock. Species A is largely endophagous and endophilic, species B is exophilic. In other sites, both species A and B will also feed on cattle, and B appears to prefer cattle. Both species also like to roost during the hot day in rock overhangs and small caves. To give some context to your answers use the IPM terminology considered in class.

A) The national malaria control agency sends in a new person to develop a malarial control strategy. (S)he recommends oiling the lakes and ponds, and intensive house spraying . Discuss why each of these two options would be a good or bad idea. In your answer consider effects on species A, species B, and malaria incidence. And remember, the idea is to help the local population.

B) Develop an alternative targeted strategy that might work well in this situation. Explain why this would be a good fit. Use only strategies that have been used successfully in the field, and avoid "just spray everything" strategies. Explain why your strategy should work.

After roughly 15 years we have the first malaria vaccine going into phase 4 trials. Meanwhile a Zika vaccine is starting phase 2b trials, only 2-3 years after the first major outbreak in Brazil.

A) Discuss in some detail why it is so much more difficult to develop a vaccine for malaria than for e.g. the Zika or rubella virus. I am looking for at least 2 reasons, and a brief explanation of those reasons. Just stating that one is complex and the other simple is insufficient. If that is what you want to say, back it up with facts.

B) Both the CRISPR bacterial defense system and the adaptive immune system in mammals have means to recognize âsignaturesâ of invading organisms. In what way are the two systems different?

The malaria control team in a given area has access to 5 different drugs, chloroquine, mefloquine, pyrimethamine, amodiaquine, and artimisinin. Nothing else will be available for the foreseeable future. Some resistance to all 5 is already observed.

A) Provide a strategy to maximize the time you can cure malaria using these 5 drugs. Explain why you want to use this strategy (what is the idea behind your plan), and be precise: when do you plan to use what drugs. What are the potential problems you can face and how do you plan to deal with them? Remember, you are working with humans, not robots.

B) Hypnozoites are forms of P. vivax and P. ovale that are dormant, with barely any metabolic activity. After long periods of time (months, a year), they can be re-activated start invading red blood cells, and causing malaria. Explain why artemisinin would or would not be a good drug for people suspected of carrying hyponozoites.

Psychology of adulthood and aging;

Here is a question related to adulthood/aging that you think science canât answer:

Does age determine adulthood?

Then you will try to demonstrate how science could answer a related question. (Change the question to): When should a person be considered an adult?

Objectives:

Students should be able to speculate as to why two variables might be correlated, identify what a correlation between variables is not telling us, and anticipate what kind of research studies could further clarify a correlation between variables.

Students should be able to define operationalization, hypothesis, and be able to describe the scientific method by which psychologists study adulthood and aging.

a-First psychological variable

b-Give it a label

c-Briefly describe this variable.

Describe how this variable can be operationalized (that is, describe exactly how you determine which category or which value of the variable applies to a particular person or situation).

Second variable that you believe is related to your first variable.

a-Give it a label.

b-Briefly describe this variable.

c-Describe how this variable can be operationalized.

Once the variables are defined, the next step is to predict the relationship between these two variables by writing a hypothesis. A hypothesis is a prediction about the relationship between two or more variables. For now, assume that there is a causal relationship between the two variables even if it would be impossible or unethical to test a causal hypothesis. This means that changing a personâs score on one of the variables (the independent variable) would cause the personâs score on the other variable (the dependent variable) to change. For example, you might say, âIncreasing the amount of violent television that a person watches will cause that person to exhibit more aggressive behaviors.â