Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
The Spinal Cord is a thick, cylindrical bundle of nerves that extends from the lower part of the brain, the , down through the hollow center of the backbone.
It is protected by the bony vertebral column (backbone), which consists of individual bones called vertebrae.
The primary function of the spinal cord is to act as a 'highway' for messages traveling between the brain and the rest of the body.
It is responsible for , which are automatic and instantaneous responses to a stimulus that do not involve the conscious part of the brain.
The spinal cord contains pairs of spinal nerves that branch out to different parts of the body.
The is the specific pathway followed by a nerve impulse during a reflex action: .
📐Formulae
💡Examples
Problem 1:
What happens when you accidentally touch a very hot plate?
Solution:
A reflex action occurs.
Explanation:
When the hand touches a hot plate (), the heat is detected by the skin (). A signal travels via the sensory nerve to the . The spinal cord immediately sends a command back via the motor nerve to the arm muscles (), causing the hand to pull away before the brain even feels the pain.
Problem 2:
Calculate the total number of nerves originating directly from the spinal cord.
Solution:
individual nerves.
Explanation:
The spinal cord has pairs of spinal nerves. Since a pair consists of nerves, the total count is nerves.
Problem 3:
Why is the spinal cord compared to a 'telephone cable'?
Solution:
Because it transmits signals.
Explanation:
Just as a telephone cable carries electrical signals between two distant points, the spinal cord carries nerve impulses between the brain and the various organs and muscles of the body.