Question

Arrange the following events in the proper sequence.

1. Efferent neuron reaches threshold and fires an action potential.
2. Afferent neuron reaches threshold and fires an action potential.
3. Effector organ responds by performing output.
4. Integrating center reaches decision about response.
5. Sensory organ detects change in the environment.
A) 2, 3, 5, 1, 4
B) 5, 2, 4, 1, 3
C) 5, 1, 4, 2, 3
D) 5, 3, 4, 2, 1
E) 3, 1, 4, 2, 5

Answer 1

The proper sequence is as follows: 5, 2, 4, 1, 3, where the sensory receptor first detects a change, information is sent to the brain for integration, and a response is triggered in an effector organ.

Step-by-step explanation:

The correct sequence of events after detecting a change in the environment to the response by an effector organ would be the following:

1. Sensory organ detects change in the environment.
2. Afferent neuron reaches threshold and fires an action potential.
3. Integrating center reaches a decision about response.
4. Efferent neuron reaches threshold and fires an action potential.
5. Effector organ responds by performing output.

This sequence starts with a sensory receptor such as a thermoreceptor in the skin that senses temperature and subsequently sends a signal to the brain for processing (integration). Finally, the motor response pathway is activated to produce a response, such as muscle contraction.