Answer:
The reflex arc follows this sequence of events
1. sensory receptor activation
2. sensory neuron activation
3.information processing
4. motor neuron activation
5. effector response
Explanation:
Reflex arc is the pathway of nerves during a reflex action. An example of a reflex arc is when we accidentally touch a hot object. First, the receptor in the skin detects a stimulus in this case the change in temperature. Second, the sensory neuron transmit the electrical impulses to the Central Nervous System for information processing. Then relay neurons connect sensory neurons to motor neurons. Third, motor neurons sends electrical impulses to an effector wherein the effector produces a response ( muscle contracts to move the hand away from the hot object. This happens in a split of seconds.
<h2>Sodium channels </h2>
Explanation:
Depolarization is a result of sodium channels opening as a result of chemical or pressure-based stimuli
- Depolarization starts when a threshold stimulus applied on a neuron via Na+ mechanically operated channels that trigger action potential
- Action potential is an efficient signaling process by which distantly located cells communicate to each other
- Depolarization of membrane potential is due to influx of Na+ via voltage gated Na+ channels
- Fast opening of voltage gated Na+ channel shifts membrane potential from -70mV to + 50mV at which voltage gated Na+ channels become inactive thus influx of Na+ abruptly stops
The toxins would enter through the Xylem.
The answer is A//////////