Explanation:

To understand why intact spinal cord is necessary for good reflex actions, let's first understand what reflex actions are. Reflex actions are rapid and involuntary responses to a stimulus that help protect the body from harm. These actions are controlled by the nervous system and do not involve conscious thought. They are quick and automatic, often occurring without any conscious effort.

Role of the Spinal Cord:
The spinal cord is a long, tubular bundle of nerves that extends from the base of the brain down to the lower back. It is a crucial part of the central nervous system and is responsible for transmitting signals between the brain and the rest of the body. The spinal cord plays a vital role in reflex actions because it allows for the rapid transmission of sensory information to the brain and motor commands back to the muscles.

Reflex Arc:
Reflex actions are mediated by a neural pathway called the reflex arc. The reflex arc involves a sensory receptor that detects a stimulus, a sensory neuron that transmits the sensory information to the spinal cord, an interneuron that relays the information within the spinal cord, a motor neuron that carries the response signal from the spinal cord to the muscles, and finally, the effector muscles that carry out the response.

Spinal Reflexes:
Many reflex actions occur entirely within the spinal cord, without involving the brain. These are known as spinal reflexes. This is because the spinal cord contains all the necessary components of the reflex arc, and it can process and respond to sensory information quickly. For example, the withdrawal reflex, which occurs when we touch a hot object, is a spinal reflex. The sensory neurons detect the heat, transmit the information to the spinal cord, which in turn sends a signal back to the muscles, causing them to contract and withdraw the hand from the hot object.

Importance of an Intact Spinal Cord:
For reflex actions to occur effectively, the spinal cord needs to be intact. Damage to the spinal cord can disrupt the transmission of signals between the sensory receptors and the muscles, leading to impaired reflex actions. If the spinal cord is damaged, the transmission of sensory information and motor commands may be disrupted or blocked, resulting in a delay or absence of reflex responses.

Conclusion:
In conclusion, an intact spinal cord is crucial for good reflex actions because it allows for the rapid transmission of sensory information and motor commands. The spinal cord plays a vital role in mediating reflex actions, and damage to it can impair these actions.

The nerve impulse is then further transported to the motor nureons which acts on the effector organs