A scientific question is a question that is based on observations and that is testableThe scientist asks a new question about the impact of climate change on the species because the results of the investigation led to new scientific questions. Correct answer: C
C is the answer because water and carbon dioxide are left over after and
mitochondria is the thing in the cell that converts everything.
Answer:
B. In the real world, random and unpredictable events occur, so the Lotka-Volterra parameters vary over time
Explanation:
Lotka-Volterra equations are mathematical models that explain biological prey-predator interactions among two species, considering the following assumptions,
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The ecosystem is isolated and closed. There is no migration.
- The whole individuals are reproductively equivalent.
- In the absence of the predator, prey shows an exponential growth rate. The prey is in the ideal environment.
- In the absence of the prey, the predator population decreases exponentially. The predator environment is also ideal, but it is limited by the prey density.
- The predation rate is proportional to the encounters rate, which also depends on density.
- The predators affect the prey populations, making it decrease proportionally to the number of prey and predators present.
- The prey population also influence the predator population, proportionally to the number of encounters between the two species.
In these equations, the variable D is the number of predators, and P the number of preys.
The parameters are always constant:
- a1: predator hunting success.
- r2: predator growth rate.
- a2: the success of the predator in hunting and feeding.
In nature, there are many factors affecting interactions. Dense-dependent factors and dense-independent factors. Also in reality there are stochastic factors. <em>Stochasticity refers to the variability in the system involving those factors that are affecting or influencing the population growth. Stochasticity might be related to good years and bad years for population growth.</em>
In a real situation, the compliance of the whole assumptions does not occur. The previously mentioned constants might vary, changing continuously the interaction among the predator and the prey. These parameters change in different degrees, resulting in different circumstances for both species.
Answer:
A. Mediator
Explanation:
Enhancers are cis regulatory sequences which are located very far - off from promoter sequence either upstream or down stream. They are capable of showing their impact even if they located far apart from promoter and Loop/Combinatorial model best describes the mechanism of action of enhancers.
The sequence of events are mentioned as under:
(1) First of all, activator binds to the enhancer;
(2) Co-activator which is also known as mediator binds to the activator;
(3) Chromatin remodelers bind with mediator at one end and heterochromatin on the other end so as to remove histones from heterochromatin and cause decondensation;
(4) General transcription factors (GTFs) bind the promoter;
(5) RNA polymerase II binds the promoter.
The enhancer forms a loop with the help of activator and mediator to reach near at promoter. In eukaryotes, activator does not interact with RNA polymerase directly, it interacts with the help of mediator so we can say that enhancer shows it's impact through protein-protein interaction.