Question

which organelle, labeled x in the diagram, is found in both plant and animal cells?
the cell wall
the cell membrane
mitochondrion
ribosome

Explanation:

Cell walls are unique to plant cells. Cell membranes, mitochondria, and ribosomes are found in both plant and animal cells. But the most general and fundamental organelle present in both and often depicted in basic cell - structure diagrams is the cell membrane which acts as a boundary for the cell.

Answer:

the cell membrane