Classify the following observation into a primary level of biological organisation.
The primary level of biological organization for the observation "The mitochondria are the powerhouses of the cell" is the organelle level.
The mitochondria are the powerhouses of the cell.
Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request.

### Instruction:
Classify the following observation into a primary level of biological organisation.

### Input:
The mitochondria are the powerhouses of the cell.

### Response:
The primary level of biological organization for the observation "The mitochondria are the powerhouses of the cell" is the organelle level.