Final answer:
The foramen magnum is the opening at the base of the skull where the spinal cord connects to the brain. It is significant in terms of nerve control because it allows for the passage of the spinal cord, which transmits sensory information and motor commands.
Step-by-step explanation:
The opening at the base of the skull where the spinal cord connects to the brain is called the foramen magnum. The foramen magnum is a large opening in the occipital bone of the skull through which the spinal cord emerges and the vertebral arteries enter the cranium. Its significance in terms of nerve control is that it allows for the passage of the spinal cord, which connects the brain to the rest of the body and is responsible for transmitting sensory information and motor commands.