3 examples would be touch, light and chemical.
and the most common signal would be chemical.
Hope this helps! (:
The last one , sorry if i’m wrong
Answer: a crack forms, magma pushes upward, magma hardens, rock moves outward.
Answer;
B. Yeast doesn't have a cell wall. The onion skin cell has a cell wall.
Explanation;
-An onion is a multicellular (consisting of many cells) plant organism.As in all plant cells, the cell of an onion peel consists of a cell wall, cell membrane, cytoplasm, nucleus and a large vacuole. The nucleus is present at the periphery of the cytoplasm.
-The vacuole is prominent and present at the center of the cell. It is surrounded by cytoplasm. The presence of a cell wall and a large vacuole are indicators that help identify plant cells, such as seen in the onion peel.
Like bacterial cells, yeast cells have cytoplasm and a membrane surrounded by a cell wall that lacks cellulose, like those of plants. Yeast cells have a nucleus.They are smaller than animal and plant cells, but slightly larger than bacteria.