الفعل المنعكس.

The video explains reflex actions as automatic, involuntary responses to sudden external stimuli, aimed at protecting the body from harm. It uses the example of withdrawing a hand from a hot object to illustrate this concept. The process involves nerve impulses traveling directly to the affected organ via sensory and motor nerves, bypassing the brain, with the spinal cord playing a crucial role. The video details how thermal stimuli are received, and nerve impulses are transmitted to cause muscle contraction, resulting in the hand being pulled away from the heat.

What is the primary purpose of a reflex action?

• To protect the body from harm

• To slow down body processes

• To enhance brain function

• To entertain the body

Which of the following is an example of a reflex action?

• Running a marathon

• Solving a math problem

• Withdrawing a hand from a hot object

• Reading a book

In a reflex action, where do nerve impulses travel directly?

• To the affected organ

• To the heart

• To the brain

• To the lungs

What role does the spinal cord play in reflex actions?

• It initiates voluntary actions

• It processes sensory information

• It is responsible for reflex actions

• It controls emotions

How do nerve impulses travel from the spinal cord to the muscles during a reflex action?

• Through the skin

• Through the brain

• Through a motor nerve fiber

• Through a sensory nerve fiber