Class 11 Biology (NCERT / JAC Board)

1. The basic structural and functional unit of the human nervous system is:

• A. Neuron
• B. Nephron
• C. Axon
• D. Neuroglia

2. Which type of neurons are predominantly found in the embryonic stage of humans?

• A. Unipolar neurons
• B. Bipolar neurons
• C. Multipolar neurons
• D. Pseudounipolar neurons

3. Bipolar neurons are characteristic components of which specialized organ in humans?

• A. Retina of the eye
• B. Cerebral cortex
• C. Spinal cord
• D. Dorsal root ganglion

4. Nissl’s granules are granular structures present in neurons composed mainly of:

• A. Ribosomes and Rough Endoplasmic Reticulum
• B. Golgi apparatus and Lysosomes
• C. Smooth Endoplasmic Reticulum and Lipids
• D. Mitochondria and Peroxisomes

5. In the resting state, the axonal membrane is comparatively more permeable to:

• A. Potassium ions (K+)
• B. Sodium ions (Na+)
• C. Calcium ions (Ca2+)
• D. Negatively charged proteins

6. The sodium-potassium pump actively transports across the axonal membrane:

• A. 3 Na+ outwards for 2 K+ into the cell
• B. 2 Na+ outwards for 3 K+ into the cell
• C. 3 K+ outwards for 2 Na+ into the cell
• D. 3 Na+ inwards for 3 K+ out of the cell

7. Rapid influx of which ion causes depolarization during an action potential?

• A. Sodium ions (Na+)
• B. Potassium ions (K+)
• C. Chloride ions (Cl-)
• D. Bicarbonate ions (HCO3-)

8. Gaps between two adjacent myelin sheaths on an axon are called:

• A. Nodes of Ranvier
• B. Synaptic clefts
• C. Schwann nodes
• D. Axon hillocks

9. Chemical transmission of nerve impulses across a synaptic cleft relies on chemicals called:

• A. Neurotransmitters
• B. Hormones
• C. Enzymes
• D. Pheromones

10. The three layers of cranial meninges from outer to inner are:

• A. Dura mater, Arachnoid, Pia mater
• B. Pia mater, Arachnoid, Dura mater
• C. Arachnoid, Dura mater, Pia mater
• D. Dura mater, Pia mater, Arachnoid

11. A thick band of nerve fibers connecting the right and left cerebral hemispheres is the:

• A. Corpus callosum
• B. Corpus albicans
• C. Corpus striatum
• D. Hypothalamus

12. Which region of the forebrain acts as a master controller for body temperature, hunger, and thirst?

• A. Hypothalamus
• B. Thalamus
• C. Epithalamus
• D. Cerebellum

13. The inner part of the cerebral hemispheres and a group of deep structures like the amygdala and hippocampus form the:

• A. Limbic system
• B. Reticular activating system
• C. Autonomic system
• D. Somatic system

14. Four round swellings present on the dorsal portion of the midbrain are together named:

• A. Corpora quadrigemina
• B. Corpora allata
• C. Corpus striatum
• D. Cerebral peduncles

15. Which part of the hindbrain coordinates voluntary muscular movements and maintains posture and balance?

• A. Cerebellum
• B. Medulla oblongata
• C. Pons
• D. Thalamus

16. The brain stem is composed of which three main divisions of the brain?

• A. Midbrain, Pons, and Medulla oblongata
• B. Forebrain, Midbrain, and Hindbrain
• C. Cerebrum, Cerebellum, and Medulla
• D. Thalamus, Hypothalamus, and Pons

17. Centers controlling cardiovascular reflexes, respiration, and gastric secretions are located in the:

• A. Medulla oblongata
• B. Cerebellum
• C. Hypothalamus
• D. Cerebrum

18. Reflex action is an involuntary response mediated primarily through the:

• A. Spinal cord
• B. Cerebral cortex
• C. Corpus callosum
• D. Cerebellum

19. The aperture in the center of the iris through which light enters the human eye is called the:

• A. Pupil
• B. Cornea
• C. Fovea
• D. Lens

20. The point on the retina with the highest visual acuity (resolution), containing densely packed cones, is the:

• A. Fovea centralis
• B. Blind spot
• C. Optic disc
• D. Choroid

21. Photoreceptor cells responsible for twilight (scotopic) vision are:

• A. Rods
• B. Cones
• C. Ganglion cells
• D. Amacrine cells

22. Rhodopsin (visual purple) is a derivative pigment formed by opsin protein and:

• A. Retinal (Vitamin A aldehyde)
• B. Retinol (Vitamin A alcohol)
• C. Calciferol (Vitamin D)
• D. Ascorbic acid (Vitamin C)

23. The middle ear contains three tiny ear ossicles arranged from outer to inner in the order of:

• A. Malleus, Incus, Stapes
• B. Stapes, Incus, Malleus
• C. Incus, Malleus, Stapes
• D. Malleus, Stapes, Incus

24. Which structure connects the middle ear cavity with the pharynx to equalize air pressure?

• A. Eustachian tube
• B. Cochlear duct
• C. Semicircular canal
• D. External auditory meatus

25. The actual organ of hearing located on the basilar membrane inside the cochlea is the:

• A. Organ of Corti
• B. Macula
• C. Crista ampullaris
• D. Otolith organ

26. Sensory structure responsible for dynamic equilibrium during body rotation is the:

• A. Crista ampullaris
• B. Macula
• C. Organ of Corti
• D. Tectorial membrane

27. Static equilibrium and linear acceleration of the body are detected by the:

• A. Macula of saccule and utricle
• B. Crista ampullaris
• C. Organ of Corti
• D. Scala vestibuli

28. The fluid filled inside the membranous labyrinth of the internal ear is:

• A. Endolymph
• B. Perilymph
• C. Hemolymph
• D. Cerebrospinal fluid

29. Somatic nervous system relays impulses from the CNS to which tissue?

• A. Skeletal muscles
• B. Smooth muscles
• C. Cardiac muscle
• D. Involuntary glands

30. Myelin sheath around peripheral nerve fibers is produced by which specialized cells?

• A. Schwann cells
• B. Oligodendrocytes
• C. Astrocytes
• D. Microglia