Nervous System - Competency-Based Question Bank (with Answers)

Section A: Case-Based Questions

Case Study 1: Accidentally touching a hot pan and withdrawing hand.

Identify the action.
- Answer: Reflex Action.
Trace the pathway.
- Answer: Receptor (Skin) -> Sensory Neuron -> Spinal Cord -> Motor Neuron -> Effector (Muscle).
Designing: Schematic diagram.
- Answer: [Description: Arc shape connecting skin to spinal cord and back to muscle].
Analysis: Why withdrawal before pain?
- Answer: The reflex arc is local to the spinal cord for speed. The message to the brain (pain perception) travels through a longer path and takes slightly more time.
Damaged motor neuron?
- Answer: The person will feel the pain (sensory works) but will not be able to move the hand (effector fails).

Case Study 2: Elderly person with Parkinson's (lack of Dopamine). 6. What is a "Synapse"?

Answer: The microscopic gap between the axon terminal of one neuron and the dendrite of the next.

Role of neurotransmitters.
- Answer: They are chemicals (like Acetylcholine or Dopamine) released from vesicles that diffuse across the synapse to transmit the impulse to the next neuron.
Creating: Analogy.
- Answer: Like a relay race where the baton (neurotransmitter) is handed from one runner to the next at the exchange zone (synapse).
Critical Thinking: Why one direction?
- Answer: Vesicles containing neurotransmitters are only present at the axon terminals, and receptors are only present on the dendrites.
Resting vs Action Potential.
- Answer: Resting: Neuron is not conducting (-70mV). Action: Reversal of polarity (+30mV) during conduction of an impulse.

Section B: Assertion-Reasoning Questions

Directions: (a) Both A/R true, R explains A; (b) Both true, R doesn't explain A; (c) A true, R false; (d) A false, R true.

Assertion (A): Cerebellum controls balance. Reason (R): It coordinates muscular activity.
- Answer: (a) Both A and R are true and R is the correct explanation.
Assertion (A): Medulla Oblongata is vital. Reason (R): It controls involuntary activities.
- Answer: (a) Both A and R are true and R is the correct explanation.
Assertion (A): Rod cells responsible for dim light vision. Reason (R): They contain Rhodopsin.
- Answer: (a) Both A and R are true and R is the correct explanation.
Assertion (A): Blind spot is area of best vision. Reason (R): It has maximum Cones.
- Answer: (d) A is false but R is true (in definition of fovea, but for blind spot, both are false). Correct Answer: (d) A is false. (Blind spot has no photoreceptors).
Assertion (A): Myopia corrected by concave lens. Reason (R): Concave lens diverges light.
- Answer: (a) Both A and R are true and R is the correct explanation.

Section C: Creating and Designing (Application & Analysis)

Designing: Nervous System classification.
- Answer: CNS (Brain, Spinal Cord) and PNS (Somatic, Autonomic: Sympathetic/Parasympathetic).
Creating: Eye User Manual (Accommodation).
- Answer: For near objects: Ciliary muscles contract -> Suspensory ligaments slacken -> Lens becomes more convex. Opposite for far objects.
Analysis: Sympathetic vs Parasympathetic.
- Answer: Sympathetic (Emergency): Increases heart rate, dilates pupil. Parasympathetic (Rest): Decreases heart rate, constricts pupil.
Designing: Cerebrum vs Cerebellum table.
- Answer: Cerebrum: Large, memory/intellect, outer grey. Cerebellum: Small, balance/coordination, outer grey with tree-like white inside.
Visualisation: Neuron diagram.
- Answer: [Description: Star-shaped cyton with a long tail]. Myelin sheath acts as insulation and increases speed of impulse (Saltatory conduction).
Application: Dizziness after spinning.
- Answer: The fluid (endolymph) in the semicircular canals continues to move due to inertia even after the head stops, sending false signals to the brain.
Creating: Anosmia effect on taste.
- Answer: Flavor is a combination of smell and taste. Without smell, food tastes bland and complex flavors cannot be distinguished.
Analysis: "All-or-None" law.
- Answer: A stimulus must reach a threshold to trigger an impulse. Once triggered, the impulse always has the same strength regardless of the stimulus intensity.
Designing: Color Blindness test.
- Answer: Use Ishihara plates (dots of different colors forming numbers).
Creating: Hearing path.
- Answer: Sound -> Pinna -> Eardrum (Vibration) -> Hammer/Anvil/Stirrup (Amplification) -> Cochlea (Fluid waves) -> Auditory Nerve.

Section D: Competency & Critical Thinking

Gray vs White Matter.
- Answer: Gray: Cytons and non-myelinated fibers. White: Myelinated axons. Brain: Gray outside. Spinal Cord: Gray inside (H-shape).
Scenario: Memory loss part.
- Answer: Cerebrum (specifically the hippocampus/temporal lobes).
Critical Thinking: Inverted image perception.
- Answer: The brain interprets the inverted image and "flips" it upright during processing.
Application: Presbyopia vs Hypermetropia.
- Answer: Hypermetropia: Eyeball too short/lens too flat. Presbyopia: Loss of lens elasticity due to age. Both cause difficulty seeing near objects.
Natural vs Conditioned Reflex.
- Answer: Natural: Inborn (e.g., blinking). Conditioned: Learned through experience (e.g., salivating at the sound of a bell).
Diagram Based: Eustachian tube.
- Answer: It equalizes air pressure on both sides of the eardrum.
Corpus Callosum function.
- Answer: It is a band of white fibers that allows communication between the left and right cerebral hemispheres.
Analysis: Binocular Vision advantage.
- Answer: Provides depth perception (stereoscopic vision) because each eye sees from a slightly different angle.
Competency: Organ of Corti.
- Answer: The sensory part of the cochlea containing hair cells that convert mechanical vibrations into electrical nerve impulses.
Case: Pupil constriction.
- Answer: Pupillary Light Reflex. Controlled by the Iris (circular muscles).
Creating: Reaction time hypothesis.
- Answer: Repeated practice strengthens neural pathways and improves coordination.
Designing: Path of light.
- Answer: Conjunctiva -> Cornea -> Aqueous Humor -> Pupil/Lens -> Vitreous Humor -> Retina.
Application: Cochlear implants.
- Answer: They bypass the ear and directly stimulate the auditory nerve with electrical signals.
Critical Thinking: Nerve cell regeneration.
- Answer: Neurons lack centrosomes and cannot undergo mitosis. They have very limited regenerative capacity.
Analysis: Stereoscopic Vision.
- Answer: Three-dimensional vision resulting from the fusion of two slightly different images.

Section E: Advanced Competency

Scenario: Stroke in left hemisphere.
- Answer: Right side paralysis. Nerve fibers cross over in the Medulla (Decussation).
Designing: Model.
- Answer: Wire (Axon), Tape (Myelin), Beads at ends (Terminals).
Application: Cataract.
- Answer: Opacity of the lens. Treated by replacing the natural lens with an artificial IOL (Intraocular Lens).
Creating: Hormonal vs Nervous table.
- Answer: [Nervous: Electrical, fast, short-lived, localized. Hormonal: Chemical, slow, long-lasting, widespread].
Case Study: Gymnast's brain part.
- Answer: Cerebellum.
Threshold Stimulus.
- Answer: The minimum intensity of a stimulus required to generate an action potential.
Critical Thinking: Smell and taste link.
- Answer: Both use chemoreceptors and their information is combined in the brain to perceive flavor.
Analysis: Aqueous vs Vitreous Humor.
- Answer: Aqueous (front): Nourishes cornea/lens. Vitreous (back): Maintains eyeball shape and supports retina.
Designing: Frequency graph.
- Answer: 20 Hz to 20,000 Hz.
Creating: Bionic Eye features.
- Answer: Sensors to detect light, a processor to convert to electrical signals, and electrodes to stimulate the optic nerve.

Section A: Case-Based Questions

Case Study 1: Accidentally touching a hot pan and withdrawing hand.

Identify the action.

Answer: Reflex Action.

Trace the pathway.

Answer: Receptor (Skin) -> Sensory Neuron -> Spinal Cord -> Motor Neuron -> Effector (Muscle).

Designing: Schematic diagram.

Answer: [Description: Arc shape connecting skin to spinal cord and back to muscle].

Analysis: Why withdrawal before pain?

Answer: The reflex arc is local to the spinal cord for speed. The message to the brain (pain perception) travels through a longer path and takes slightly more time.

Damaged motor neuron?

Answer: The person will feel the pain (sensory works) but will not be able to move the hand (effector fails).

Case Study 2: Elderly person with Parkinson's (lack of Dopamine). 6. What is a "Synapse"?

Answer: The microscopic gap between the axon terminal of one neuron and the dendrite of the next.

Role of neurotransmitters.

Answer: They are chemicals (like Acetylcholine or Dopamine) released from vesicles that diffuse across the synapse to transmit the impulse to the next neuron.

Creating: Analogy.

Answer: Like a relay race where the baton (neurotransmitter) is handed from one runner to the next at the exchange zone (synapse).

Critical Thinking: Why one direction?

Answer: Vesicles containing neurotransmitters are only present at the axon terminals, and receptors are only present on the dendrites.

Resting vs Action Potential.

Answer: Resting: Neuron is not conducting (-70mV). Action: Reversal of polarity (+30mV) during conduction of an impulse.

Section B: Assertion-Reasoning Questions

Directions: (a) Both A/R true, R explains A; (b) Both true, R doesn't explain A; (c) A true, R false; (d) A false, R true.

Assertion (A): Cerebellum controls balance. Reason (R): It coordinates muscular activity.

Answer: (a) Both A and R are true and R is the correct explanation.

Assertion (A): Medulla Oblongata is vital. Reason (R): It controls involuntary activities.

Answer: (a) Both A and R are true and R is the correct explanation.

Assertion (A): Rod cells responsible for dim light vision. Reason (R): They contain Rhodopsin.

Answer: (a) Both A and R are true and R is the correct explanation.

Assertion (A): Blind spot is area of best vision. Reason (R): It has maximum Cones.

Answer: (d) A is false but R is true (in definition of fovea, but for blind spot, both are false). Correct Answer: (d) A is false. (Blind spot has no photoreceptors).

Assertion (A): Myopia corrected by concave lens. Reason (R): Concave lens diverges light.

Answer: (a) Both A and R are true and R is the correct explanation.

Section C: Creating and Designing (Application & Analysis)

Designing: Nervous System classification.

Answer: CNS (Brain, Spinal Cord) and PNS (Somatic, Autonomic: Sympathetic/Parasympathetic).

Creating: Eye User Manual (Accommodation).

Answer: For near objects: Ciliary muscles contract -> Suspensory ligaments slacken -> Lens becomes more convex. Opposite for far objects.

Analysis: Sympathetic vs Parasympathetic.

Answer: Sympathetic (Emergency): Increases heart rate, dilates pupil. Parasympathetic (Rest): Decreases heart rate, constricts pupil.

Designing: Cerebrum vs Cerebellum table.

Answer: Cerebrum: Large, memory/intellect, outer grey. Cerebellum: Small, balance/coordination, outer grey with tree-like white inside.

Visualisation: Neuron diagram.

Answer: [Description: Star-shaped cyton with a long tail]. Myelin sheath acts as insulation and increases speed of impulse (Saltatory conduction).

Application: Dizziness after spinning.

Answer: The fluid (endolymph) in the semicircular canals continues to move due to inertia even after the head stops, sending false signals to the brain.

Creating: Anosmia effect on taste.

Answer: Flavor is a combination of smell and taste. Without smell, food tastes bland and complex flavors cannot be distinguished.

Analysis: "All-or-None" law.

Answer: A stimulus must reach a threshold to trigger an impulse. Once triggered, the impulse always has the same strength regardless of the stimulus intensity.

Designing: Color Blindness test.

Answer: Use Ishihara plates (dots of different colors forming numbers).

Creating: Hearing path.

Answer: Sound -> Pinna -> Eardrum (Vibration) -> Hammer/Anvil/Stirrup (Amplification) -> Cochlea (Fluid waves) -> Auditory Nerve.

Section D: Competency & Critical Thinking

Gray vs White Matter.

Answer: Gray: Cytons and non-myelinated fibers. White: Myelinated axons. Brain: Gray outside. Spinal Cord: Gray inside (H-shape).

Scenario: Memory loss part.

Answer: Cerebrum (specifically the hippocampus/temporal lobes).

Critical Thinking: Inverted image perception.

Answer: The brain interprets the inverted image and "flips" it upright during processing.

Application: Presbyopia vs Hypermetropia.

Answer: Hypermetropia: Eyeball too short/lens too flat. Presbyopia: Loss of lens elasticity due to age. Both cause difficulty seeing near objects.

Natural vs Conditioned Reflex.

Answer: Natural: Inborn (e.g., blinking). Conditioned: Learned through experience (e.g., salivating at the sound of a bell).

Diagram Based: Eustachian tube.

Answer: It equalizes air pressure on both sides of the eardrum.

Corpus Callosum function.

Answer: It is a band of white fibers that allows communication between the left and right cerebral hemispheres.

Analysis: Binocular Vision advantage.

Answer: Provides depth perception (stereoscopic vision) because each eye sees from a slightly different angle.

Competency: Organ of Corti.

Answer: The sensory part of the cochlea containing hair cells that convert mechanical vibrations into electrical nerve impulses.

Case: Pupil constriction.

Answer: Pupillary Light Reflex. Controlled by the Iris (circular muscles).

Creating: Reaction time hypothesis.

Answer: Repeated practice strengthens neural pathways and improves coordination.

Designing: Path of light.

Answer: Conjunctiva -> Cornea -> Aqueous Humor -> Pupil/Lens -> Vitreous Humor -> Retina.

Application: Cochlear implants.

Answer: They bypass the ear and directly stimulate the auditory nerve with electrical signals.

Critical Thinking: Nerve cell regeneration.

Answer: Neurons lack centrosomes and cannot undergo mitosis. They have very limited regenerative capacity.

Analysis: Stereoscopic Vision.

Answer: Three-dimensional vision resulting from the fusion of two slightly different images.

Section E: Advanced Competency

Scenario: Stroke in left hemisphere.

Answer: Right side paralysis. Nerve fibers cross over in the Medulla (Decussation).

Designing: Model.

Answer: Wire (Axon), Tape (Myelin), Beads at ends (Terminals).

Application: Cataract.

Answer: Opacity of the lens. Treated by replacing the natural lens with an artificial IOL (Intraocular Lens).

Creating: Hormonal vs Nervous table.

Answer: [Nervous: Electrical, fast, short-lived, localized. Hormonal: Chemical, slow, long-lasting, widespread].

Case Study: Gymnast's brain part.

Answer: Cerebellum.

Threshold Stimulus.

Answer: The minimum intensity of a stimulus required to generate an action potential.

Critical Thinking: Smell and taste link.

Answer: Both use chemoreceptors and their information is combined in the brain to perceive flavor.

Analysis: Aqueous vs Vitreous Humor.

Answer: Aqueous (front): Nourishes cornea/lens. Vitreous (back): Maintains eyeball shape and supports retina.

Designing: Frequency graph.

Answer: 20 Hz to 20,000 Hz.

Creating: Bionic Eye features.

Answer: Sensors to detect light, a processor to convert to electrical signals, and electrodes to stimulate the optic nerve.

Nervous System

Nervous System - Competency-Based Question Bank (with Answers)

Section A: Case-Based Questions

Section B: Assertion-Reasoning Questions

Section C: Creating and Designing (Application & Analysis)

Section D: Competency & Critical Thinking

Section E: Advanced Competency

On this page

BioBot

Nervous System

Nervous System - Competency-Based Question Bank (with Answers)

Section A: Case-Based Questions

Section B: Assertion-Reasoning Questions

Section C: Creating and Designing (Application & Analysis)

Section D: Competency & Critical Thinking

Section E: Advanced Competency

On this page