Don't understand how this was particularly hard; I feel people are just lazy.
The answer is ecosystem.
This is because c refers to a single animal or species. (i.e. population of wolves in said ecosystem.)
Community would be specifically the animals living in an area.
And a landform is the natural feature of a solid surface.
Answer:
Ribosomes, Cell membrane
Explanation:
Ribosomes can be described as structures which are involved in the production of proteins. Ribosomes are hence known to be the protein manufacturing units of a cell. As enzymes are also proteins,they will be synthesized in the ribosomes.
Cell membrane can be described as the membrane which is present outside the cell or which separates the cell from the external environment.
For an enzyme to pass through the external environment, it will have to pass through the ribosomes and the cell membrane.
The answer is all of the above
