Stimuli and Responses

Free sample questions

Stimuli and Responses — sample Science questions with answers

1. Question 1

   What is the main function of the human nervous system?

   • AControls and coordinates responses to stimuli
   • BSupplies oxygen to the whole body
   • CDigests food that is eaten
   • DRemoves waste products from the body

   Answer: A. Controls and coordinates responses to stimuli

   The nervous system functions to detect stimuli, transmit impulses, and produce appropriate responses.

2. Question 2

   Which part of the neuron functions to receive impulses from other neurons?

   • ADendrite
   • BAxon
   • CNucleus
   • DSynapse

   Answer: A. Dendrite

   Dendrites receive impulses from other neurons or from receptors and transmit them to the cell body.

3. Question 3

   Which type of neuron transmits impulses from receptors to the central nervous system?

   • ASensory neuron
   • BMotor neuron
   • CInterneuron
   • DEfferent neuron

   Answer: A. Sensory neuron

   Sensory neurons carry impulses from receptors (senses) to the brain or spinal cord.

4. Question 4

   What response occurs when your hand touches a hot surface?

   • AHand continues to hold the surface
   • BHand is automatically withdrawn
   • CHand becomes numb
   • DHand trembles

   Answer: B. Hand is automatically withdrawn

   This is a reflex action involving the spinal cord as the integration centre to avoid injury.

5. Question 5

   The diagram shows a reflex arc. Which is the correct impulse pathway?

   • AReceptor $\to$ sensory neuron $\to$ interneuron $\to$ motor neuron $\to$ effector
   • BEffector $\to$ motor neuron $\to$ interneuron $\to$ sensory neuron $\to$ receptor
   • CReceptor $\to$ motor neuron $\to$ brain $\to$ sensory neuron $\to$ effector
   • DSensory neuron $\to$ receptor $\to$ interneuron $\to$ effector $\to$ motor neuron

   Answer: A. Receptor $\rightarrow$ sensory neuron $\rightarrow$ interneuron $\rightarrow$ motor neuron $\rightarrow$ effector

   Simple reflex arc: stimulus is detected by receptor, impulse travels through sensory neuron to spinal cord, then interneuron connects to motor neuron, and effector produces a response.