Weathering and soil formation.
Answer:
A food chain is a representation of what eats what in an ecosystem.
A combination of food chains is termed as a food web.
Example of two food chains in a food web are :
Example No 1:
Plant----- Grasshopper------ Frog---snake--- bacteria
Example No 2:
Plant---- rabbits---- fox---- bacteria
In a food chain, producers are usually plants and algae which are able to make their own food. Consumers feed on the plants. In example no 1, grasshoppers are primary consumers, frogs are secondary consumers, snakes are tertiary consumers.
In example no 2,plants are producers, rabbits are primary consumers and foxed are secondary consumers.
Decomposers are organisms that feed on the dead organisms in a food chain. In both the examples of food chain, bacteria are the decomposers.
Cell Membrane = Controls what comes into and out of a cell; found in plant and animal cells
Answer:
Weather conditions
Explanation:
Food can be limited based on location, however, scientists can control what kind of food it is. Soil can be tested and experimented on. There can be a lot of it and different kinds. Space is fought over because of territories and is limited compared to how many people and animals there are. Weather is not something that can be controlled in an experiment since it is sporadic.