Answer: C - spiral staircase
Explanation:
Answer:
Soil can become waterlogged. The water can cut off the air supply to the roots and to the organisms that live in the soil. If the roots do not receive enough oxygen, the plants will die because they rely on oxygen to complete photosynthesis.
Explanation:
Answer:
Food must be broken down into nutrients for the body to use for energy, development, and cell repair. Before the blood absorbs and transports nutrients to cells in the body, food and drink must be broken down into smaller nutrient molecules.
A.The radiation damages a person’s DNA, which causes a mutation that makes the cell divide out of control.
A. parasitism. The plasmodium is helped while the human host, harmed.
b. mutualism. The bacteria is supplied with a living environment while the host human is supplied with vitamin K
