Question

It is 7:00am and your alarm is ringing. You reach over to turn it off.

Describe what just happened in your nervous system.

Include the following terms in your answer: frontal lobe, action potential, ACh, brain stem, synapse, neurotransmitter, temporal lobe, axon terminal, motor nerve, spinal cord.

Answer 1

The above diagram explains the reason for the above mentioned response to the ringing of alarm.

1) Stimuli is captured by the sensory oragans like eyes, ears, nose, skin etc.

2) Resulting in activation of sensory neurons

3) This gathered up information is passed on to the spinal cord.

4) motor neurons are activated

5) Effector shows its response according to the information

Frontal lobe of the brain is responsible for three mains functions- 1) voluntary motor activity 2) speaking ability 3) elaboration of thoughts.

Temporal lobes are located on each sides of the brain and helps in 1) processing of memory and 2) auditory information and 3) speech and language function.

In the case mentioned above there was a stimuli in the form of noise which was captured by the ears. This information was processed in the temporal lobe that triggered the frontal lobe to generate voulantary motor response. The information captured by ears was passed on to the sensory neuron which further passed this information to the motor neuron causing the effector muscles ( in this case hands) to reach out to the alarm and switch it off. This is called Reflex action.

Nervous tissues comprises of neurons and neuroglia Most neurons consist of three basic parts: a cell body, Axons and Dendrites. When a stimulus is received the signal is transmitted first through the cell body passing through the axons and releasing the signal to the next neuron in line or the effector muscles. the entire mechanism is based on the signal transduction based on voltage differences which include electrically charged ions like sodium, potassium, chloride and calcium. A decrease in a certain threshold maintained by the neurons will lead to the generation of action potential which travels through neurons travelling in one direction from axons to dendrons thereby passing the signal.

image showing transmission of signal by releasing neurotransmiiter at the synapse.

diagram summary- the stimuli captured in the form of sound was transmitted through the sensory neuron leading to the generation of action potential. Voltage gated ion channels open as a result of action potential generated causing influx of calcium ions.These ions facilitate the release of neurotransmitters such as Acetylcholine (Ach)  at the synapse. Which is captured by the following neuron or effector.