Question

Sarah stepped on a pin that was on the floor causing the pin to be pushed on to her skin. The pressure the pin had on the foot caused three primary sensory neurons to activate and release neurotransmitters to their corresponding secondary neuron.

1. What type of stimulus-response occurred?

A) Lateral inhibition

B) Adequate stimulus

C) Labeled line coding

D) Frequency coding

E) Population coding

2. How did Sarah know where the pin she stepped on was localized?

A) The CNS has the ability to understand which signal is coming from each specific group which allows modality to occur.

B) The stimulus in the middle receives the most stimulation, thus, the middle secondary neuron will be able to send its signal through the pathway. Causing a contrast between the center and sides of the receptive field allowing a precise localization to occur.

C) Many receptors work together to send information to the CNS. When comparing the input from all the receptors, the CNS is able to conclude the quality, spatial and temporal characteristics of the stimulus

D) Localization of lateral inhibition could be calculated through a single sensory neuron

E) You can find lateral inhibition by counting the amount of frequency of an action potential that is coming from a receptor

3. When Sarah stepped on the pin, what was the first step that occurred?

A) A release of neurotransmitter reached a considerable graded potential

B) There is an excitatory postsynaptic potential that occurs on the secondary afferent neuron

C) Hyperpolarization of the terminal button caused calcium channels to open

D) An endogenous opioid is released which is diffused across, it grabs onto the opiate receptor then it opens the gate, and potassium rushes out

E) Exocytose is not found

Answer 1

1. The activation of the three primary sensory neurons by the stepping on a pin activated the labelled line stimulus. Hence, the correct answer is option 'c'.

2. The localization of the pain is a result of the working together of multiple neurons to send information to the CNS. When comparing the input from all the receptors, the CNS is able to conclude the quality, spatial and temporal characteristics of the stimulus.

Hence, the correct answer is option 'c'.

3. The very first step in a neural pathway is the release of the neurotransmitter. Hence, the correct answer is option 'a'.