The correct answer for the question that is being presented above is this one: "B. building of the transcontinental railroad --> disappearance of the frontier." The pair of events that did the first event most directly influence the second is the building of the transcontinental railroad --> disappearance of the frontier.
The answer is: Resource Constrained
In business, Resource constrained refers to the situation when the company does not possess all the things that it needs in order to complete a certain project.
This could include things such as lack of equipment, lack of resources materials, lack of capital injection, lack of knowledge in the relevant sectors, etc.
All animals and plants have evolved to time the periods of their reproduction in accordance to the available resources, or rather they are more abundant and easier to get.
Explanation:
As examples we can take the apricot tree, as a plant, and the lynx, as an animal.
The apricot tree starts the process of reproduction when the temperatures are higher and when there is more sunlight. This usually starts from the beginning or middle of March. The reason as to why the apricot starts the reproduction during this period is because the warmer weather enables the bees to come out and pollinate it, while the sunlight is crucial because as a plant the apricot uses it for the process of photosynthesis.
The lynx is member of the cat family. It is a predator so it has timed its reproduction in accordance to the reproduction of its prey. The reason for this is that the lynx will need more food when it has cubs, so it is much easier to get more food when its prey has offspring as well as they are easy target, but also the mothers tend to be more defensive and often try to stand up to the predator which also makes them much easier targets.
Neurotransmitters work locally and their actions are very fast. Both hormones and neurotransmitters act as chemical messengers in the body. However, neurotransmitters' actions are short-lived while hormones act for longer periods of time. Neurotransmitters are delivered through the bloodstream, whereas hormones are found primarily in the synaptic cleft. Hormones are mostly released by glands, whereas neurotransmitters are made in the cell body of the neuron.
