Reflex Action and Reflex Arc_Unsolved Paper
Chapter: Control and Coordination | Topic: Reflex Action and Reflex Arc
REFLEX ACTION AND REFLEX ARC_UNSOLVED PAPER
Topic: Reflex Action and Reflex Arc
Q1. A reflex action is best described as:
- A slow and voluntary response
- A quick and automatic response to a stimulus
- A response controlled only by muscles
- A response that occurs only during sleep
Q2. Which part of the central nervous system generally coordinates many simple reflex actions?
- Cerebrum
- Spinal cord
- Cerebellum
- Medulla
Q3.Which type of neuron carries nerve impulses from a receptor toward the central nervous system?
- Motor neuron
- Sensory neuron
- Secretory neuron
- Muscle neuron
Q4. In a reflex arc, the structure that performs the response is called the:
- Receptor
- Relay neuron
- Effector
- Synapse
Q5. A student accidentally touches a hot steel lunch box and immediately pulls their hand away. Which event acts as the stimulus?
- Movement of the hand
- Heat from the hot surface
- Contraction of the arm muscles
- Message sent to the brain
Q6. Which sequence correctly represents the general pathway of a reflex arc?
- Effector → Motor neuron → Receptor → Sensory neuron
- Receptor → Sensory neuron → Relay neuron → Motor neuron → Effector
- Brain → Receptor → Motor neuron → Effector
- Motor neuron → Receptor → Spinal cord → Sensory neuron
Short questions
Q1. Define reflex action. Give one example from everyday life.
Q2. What is a reflex arc? Why is it important for the body?
Q3. Differentiate between a reflex action and a voluntary action.
Q4. A student suddenly blinks when dust enters the eye. Identify the stimulus and describe the response.
Q5. What are receptors and effectors? State one example of each involved in a reflex action.
Q6. Why are many reflex actions coordinated through the spinal cord?
Q1. Draw a neat and properly labelled diagram of a reflex arc. Explain the role of the receptor, sensory neuron, relay neuron, motor neuron, and effector.
Q2. Explain the sequence of events that occurs when a person accidentally touches a hot cooking utensil. Describe how the nervous system produces a rapid protective response.
Q3. During a school sports activity, a student suddenly loses balance and quickly stretches out their arms to avoid falling. Explain how rapid nervous coordination helps protect the body. Differentiate this response from a consciously planned movement.
Q1. A biology student records the response time of a participant during five trials:
Answer the following:
Calculate the total response time for all five trials.
Calculate the average response time.
Identify the shortest and longest response times.
Calculate the difference between the longest and shortest response times.
Q2. During a classroom activity, 40 students were asked to identify examples of reflex actions. The results were recorded as follows:
Answer the following:
What percentage of students gave correct responses?
How many students gave either partially correct or incorrect responses?
What percentage of students did not give a fully correct response?
Suggest one reason why some students may confuse reflex actions with voluntary actions.
Q3. Read the following situation:
During a school laboratory activity, a student accidentally touches a heated metal stand. The skin detects the heat, a nerve message travels through the nervous system, and the student quickly withdraws their hand.
Based on your understanding of reflex action and reflex arc:
Identify the stimulus in this situation.
State the role of the receptor.
Describe the pathway followed by the nerve impulse.
Identify the effector involved in producing the response.
Explain why a rapid response is important in this situation.