Answer: There must be diseases and natural disasters present in an ecosystem.
Explanation: The other two answers must be present for it to be natural selection.
Answer:
The cell membrane gives the cell its structure and regulates the materials that enter and leave the cell. ... Instead, these molecules must pass through proteins that are embedded in the membrane. In this way, the cell can control the rate of diffusion of these substances.
Explanation: Hope this helped!!!!
75%will not get it
25% will
25%have tt
50% have Tt
25% have TT
2) cell-tissue-organ-organ system