The arrangement of tubules within horn cells is which pattern?

• A. Linear
• B. Circular
• C. Random
• D. Spiral

Answer: (D)

In horn cells, the cytoskeletal tubules (microtubules) are organized in a spiral pattern to support the long, slender structure of motor neurons and organize transport along their processes. This spiral arrangement provides a continuous, twist-friendly track for motor proteins to move cargo—like neurotransmitters and organelles—efficiently from the cell body out to the axon terminals and back. It also helps maintain structural integrity during bending and growth, without creating knots or blocks in transport.

A linear arrangement would limit flexibility and adaptation to the neuron's curves; a circular pattern would hamper long-range trafficking by trapping movement; and a random layout would disrupt directional transport and cargo delivery. The spiral pattern thus best supports the specialized needs of horn cells for sustained, orderly intracellular transport.