Answer:
None of the above.
Explanation:
GTPases are the regulatory proteins that are involved in the signal transduction pathway involving the activation of the G protein. The mutation in these proteins cal lead to cancer cells.
The guanine nucleotide exchange factors (GEF) allows the replacement of GDP by GTP. They activates the GTPase activity of the cell and can also activate the multiple GTPase activity of the cell. The Ras superfamily is activated by the GEF.
Thus, the correct answer is option (d).
They can’t live in dry areas because fungi need to be able to trap moisture since their broad tops can dry out
Answer:
The simultaneous effect of a predator population on a prey population and a prey population on a predator population over time.
Explanation:
The mathematical models of Lotka-Volterra equations explain the existing interaction between species in which prey and predator influence and affect each other. The model follows a few assumptions,
- 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.
- When there is no prey, the predator population decreases exponentially because of the lack of food. The predator environment is ideal, but it is limited by prey density.
- The predation rate is proportional to the encounters rate, which also depends on density.
- The predators affect the prey populations, inducing its decrease proportionally to the number of prey and predators present.
- The prey population also influences 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 prey items.
The parameters are always constant:
• r1: prey growth rate.
• a1: predator hunting success.
• r2: predator growth rate.
• a2: the success of the predator in hunting and feeding.
In nature, many factors affect interactions, such as dense-dependent factors and dense-independent factors. Also, in reality, there are stochastic factors. Stochasticity refers to the variability in the system involving those factors that are affecting or influencing population growth. Stochasticity might be related to good years and bad years for population growth.
In real situations, the compliance of the whole assumption does not occur. The previously mentioned constants might vary, constantly changing the interaction between the predator and the prey. These parameters change in different degrees, resulting in varying circumstances for both species.
<span>Stability is often preceded by a "crash" since the growing population eventually is too large for the available resources.
Stability refers to population stability. The growth of the population may destabilize the population stability.
The population size may become so large, so there will be no enough resources for species to survive. </span>
