25 questions in 25 minutes on the NTA computer-based test interface, all from Locomotion and Movement. +4 / -1 marking, instant score, full solutions. Free, no login.
A chapter test is the fastest honest check on whether a chapter has actually landed. This one draws 25 questions from Locomotion and Movement, of which 14 are real NEET previous-year questions and 0 sit at the harder end of the bank. Sit it in one 25-minute block, the way you would in the hall.
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Duration: 180 minutes · 180 questions · 720 marks maximum
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NEET CBT mock test: common questions
How many questions are in this Locomotion and Movement mock test?
25 questions in 25 minutes, marked +4 for a correct answer and -1 for a wrong one, exactly like the real paper. 14 of them are NEET previous-year questions.
Is this the same interface as the real NEET CBT?
Yes. On-screen countdown, colour-coded question palette, Save & Next, Clear Response and Mark for Review, then an instant score with full solutions.
Should I take this before or after revising Locomotion and Movement?
Both, and that is the point. Take it cold to find out what you actually do not know, revise from the chapter notes, then retake it to confirm the gap closed.
All 25 questions with answers and solutions
The complete paper in text form, with the correct option and a worked explanation for every question. Sit the timed test above first: the score is only worth having if you earn it. Then open this to revise, or to re-read a question you got wrong without replaying the whole paper.
Show all 25 questions with answers and solutions
Zoology
- Q1Intervertebral disc is found in the vertebral column of
- Reptiles
- Mammals
- Amphibians
- Birds
Answer: (B) Mammals
C. Tests: which vertebrate class carries fibrocartilaginous pads between the vertebral centra. Why C: Mammals have acoelous vertebrae, that is centra with flat ends. The gap between two flat faces is filled by a fibrocartilaginous intervertebral disc that cushions compression and still allows limited bending. Humans, being mammals, carry 23 such discs down the column. Why not A: birds have heterocoelous, saddle shaped cervical centra that slide directly on one another, so no disc is interposed. Why not B: reptiles have procoelous centra that fit together as a ball and socket, which needs no cushioning pad [misconception B: “every land vertebrate needs a shock absorbing disc”]. Why not D: amphibian centra are procoelous or opisthocoelous and also articulate directly, without discs. Remember: only flat ended (acoelous) mammalian centra need a disc packed in between.
- Q2The lower jaw in mammals is made up of:
- Angulars
- Mandible
- Maxilla
- Dentary
Answer: (D) Dentary
In mammals the lower jaw is a single tooth-bearing membrane bone, the dentary, on each side. The maxilla is the upper jaw; ‘mandible’ is the general term but the specific bone forming it in mammals is the dentary; angular is a jaw bone of non-mammalian vertebrates.
- Q3Knee joint and elbow joint are examples of
- Hinge joint
- Ball and socket joint
- Saddle joint
- Pivot joint
Answer: (A) Hinge joint
D. Tests: matching a synovial joint to the plane of movement it allows. Why D: Both the knee and the elbow bend and straighten in a single plane only, like a door on its hinge, with no rotation or side to side swing. A synovial joint that permits movement in one plane about one axis is a hinge joint, so both are hinge joints. Why not A: A saddle joint has reciprocally concave and convex surfaces allowing movement in two planes, and its NCERT example is the carpal and metacarpal joint of the thumb, not the knee or elbow [misconception A: “any joint that both bends and grips is a saddle joint”]. Why not B: A ball and socket joint moves in all planes and rotates, and its examples are the shoulder and the hip, which is precisely what the knee and elbow cannot do [misconception B: “all large limb joints are ball and socket”]. Why not C: A pivot joint allows rotation about a longitudinal axis only, as between the atlas and the axis vertebrae, and neither knee nor elbow rotates that way [misconception C: “the forearm turns, so the elbow must be a pivot”]. Remember: one plane of movement means hinge, and knee plus elbow are the standard pair.
- Q4The total number of bones in the human axial skeleton is:
- 206
- 80
- 40
- 126
Answer: (B) 80
The axial skeleton has 80 bones (skull 29, vertebral column 26, sternum 1, ribs 24). The appendicular skeleton has 126, giving a total of 206.
- Q5The contractile protein of skeletal muscle involving ATPase activity is:
- Myosin
- α-actinin
- Troponin
- Tropomyosin
Answer: (A) Myosin
Myosin is the contractile protein whose globular head carries ATPase activity, hydrolysing ATP to power the cross-bridge cycle. Troponin and tropomyosin are regulatory (no ATPase), and α-actinin is a Z-line anchoring protein.
- Q6Gout is a type of disorder which leads to:
- Inflammation of joints due to accumulation of uric acid crystals
- Inflammation of joints due to cartilage degeneration
- Weakening of bones due to low calcium level
- Weakening of bones due to decreased bone mass
Answer: (A) Inflammation of joints due to accumulation of uric acid crystals
B. Tests: the biochemical cause behind gouty joint inflammation. Why B: Gout follows hyperuricaemia. Uric acid is the end product of purine breakdown, and in excess it crystallises as sodium urate inside and around synovial joints. Those needle like crystals set off an acute inflammatory response, giving the classic hot, swollen, painful big toe. Why not A: bones weakened by low calcium describe rickets or osteomalacia, which is a mineralisation problem and not a joint crystal disease. Why not C: loss of bone mass with easy fractures is osteoporosis, driven mainly by falling estrogen, not by uric acid [misconception C: “gout thins the bone rather than inflaming the joint”]. Why not D: joint inflammation that follows cartilage wear is osteoarthritis; the symptom half matches gout but the cause named is wrong, which is the whole trap. Remember: gout = uric acid crystals in the joint, osteoarthritis = worn cartilage, osteoporosis = lost bone mass.
- Q7Which of the following joints would allow no movements?
- Ball and socket joint
- Cartilaginous joint
- Fibrous joint
- Synovial joint
Answer: (C) Fibrous joint
C. Tests: ranking the three structural classes of joints by the movement each permits. Why C: In a fibrous joint the articulating bones are held together by dense fibrous connective tissue with no cavity and no cartilage pad between them. The flat skull bones joined by sutures are the standard example, and because the fibrous tissue locks the edges together, this class allows no movement at all. Why not A: A synovial joint has a fluid filled cavity between the bone ends, which is exactly the arrangement that permits considerable movement, so it is the most mobile class rather than the immobile one [misconception A: “synovial fluid cushions the bones so they cannot move”]. Why not B: A ball and socket joint is a subtype of the synovial class, as at the shoulder and hip, and it is the freest of all, moving in every plane and rotating [misconception B: “a bone locked inside a socket is held rigid”]. Why not D: In a cartilaginous joint the bones are joined by cartilage, as between adjacent vertebrae, which permits limited movement, so movement is restricted but not absent [misconception D: “limited movement and no movement are the same thing”]. Remember: fibrous means none, cartilaginous means limited, synovial means free.
- Q8Ribs are attached to
- Scapula
- Clavicle
- Ilium
- Sternum
Answer: (D) Sternum
B. Tests: the ventral attachment of the human rib cage. Why B: Each typical rib is attached dorsally to a thoracic vertebra and ventrally to the sternum through hyaline cartilage. The first seven pairs (true ribs) join the sternum directly and pairs 8 to 10 (false ribs) join it indirectly through the cartilage of the seventh pair, so the ventral anchor among these options is the sternum. Why not A: the scapula is a pectoral girdle bone that lies over the back of the rib cage without articulating with any rib. Why not C: the clavicle articulates with the sternum and the scapula, not with a rib [misconception C: “the collar bone is part of the rib cage”]. Why not D: the ilium is a hip bone of the pelvic girdle, well below the thorax. Remember: ribs run from vertebra behind to sternum in front, 7 true, 3 false, 2 floating.
- Q9Sutures between the flat bones of the skull are examples of:
- Fibrous joints
- Cartilaginous joints
- Pivot joints
- Synovial joints
Answer: (A) Fibrous joints
Skull sutures are fibrous joints – immovable joints in which bones are held together by dense fibrous connective tissue.
- Q10Myasthenia gravis is best described as:
- Accumulation of uric acid crystals in joints
- Loss of bone mass due to low oestrogen
- An autoimmune disorder affecting the neuromuscular junction
- A genetic degeneration of muscle fibres
Answer: (C) An autoimmune disorder affecting the neuromuscular junction
Myasthenia gravis is an autoimmune disorder affecting the neuromuscular junction, leading to fatigue, weakening and paralysis of skeletal muscles.
- Q11During muscle contraction in humans, the
- actin filaments shorten.
- A, H and I bands shorten
- sarcomere does not shorten
- A band remains same
Answer: (D) A band remains same
B. Tests: which single band of the sarcomere is unchanged when a muscle contracts. Why B: The A band is defined as the region occupied by the thick myosin filaments. Contraction works by the thin filaments sliding inwards over the thick ones, and no filament alters its own length, so the extent of the myosin filaments and therefore the width of the A band is unchanged. Only the myosin free portions change, that is the I band narrows and the H zone shrinks or disappears. Why not A: The sarcomere is the distance between two successive Z lines, and because the thin filaments anchored to the Z lines are pulled towards the centre, the Z lines are dragged closer and the sarcomere does shorten [misconception A: “if the filaments stay the same length, nothing shortens”]. Why not C: The H and I regions do shrink, but including the A band spoils the statement, since that band is fixed by thick filament length [misconception C: “contraction compresses the whole sarcomere uniformly”]. Why not D: Actin filaments slide, they never shorten. The narrowing I band records increased overlap, not loss of actin length [misconception D: “the thin filament reels itself in”]. Remember: the A band is the ruler that never changes; measure everything else against it.
- Q12Select the correct statement with respect to disorders of muscles in humans.
- Accumulation of urea and creatine in the joints causes their inflammation.
- An overdose of vitamin D causes osteoporosis.
- Rapid contractions of skeletal muscles cause muscle dystrophy.
- Failure of neuromuscular transmission in myasthenia gravis can prevent normal swallowing.
Answer: (D) Failure of neuromuscular transmission in myasthenia gravis can prevent normal swallowing.
A. Tests: pairing each locomotory disorder with its true cause, then picking the one statement that survives. Why A: In myasthenia gravis, autoantibodies block the acetylcholine receptors of the motor end plate, so transmission from nerve to muscle fails. Swallowing is carried out by skeletal muscle of the pharynx and upper oesophagus, which is under exactly this kind of motor control, so weak transmission there produces difficulty in swallowing along with drooping eyelids and general fatigue. The statement is therefore correct. Why not B: The crystals that accumulate in a joint and inflame it in gout are uric acid crystals, the end product of purine metabolism, not urea and not creatine [misconception B: “any nitrogenous waste left in the body can crystallise in joints”]. Why not C: Osteoporosis is a loss of bone mass linked to ageing and to a fall in oestrogen level. Vitamin D actually promotes calcium absorption, so an excess of it does not thin bone; a deficiency of vitamin D is what causes soft bone in rickets [misconception C: “too much of a bone vitamin must weaken bone”]. Why not D: Muscular dystrophy is an inherited genetic disorder causing progressive degeneration of muscle fibres. Rapid repeated contraction with an inadequate oxygen supply causes lactic acid build up, cramp and fatigue, which is a different and reversible thing [misconception D: “overworking a muscle causes dystrophy”]. Remember: gout is uric acid, dystrophy is genetic, osteoporosis is low oestrogen, myasthenia gravis is the blocked junction.
- Q13Which combination correctly matches the structure with its description?
- Sarcoplasmic reticulum - plasma membrane of fibre
- M-line - centre of the I-band
- Sarcolemma - stores calcium ions
- Sarcoplasm - cytoplasm of muscle fibre
Answer: (D) Sarcoplasm - cytoplasm of muscle fibre
Sarcoplasm is the cytoplasm of the muscle fibre. The sarcolemma is the plasma membrane; the sarcoplasmic reticulum stores Ca²⁺; the M-line lies in the centre of the A-band (H-zone), not the I-band.
- Q14The total number of bones in the hind limb of man is:
- 21
- 30
- 24
- 14
Answer: (B) 30
One hind limb = femur 1 + tibia 1 + fibula 1 + patella 1 + tarsals 7 + metatarsals 5 + phalanges 14 = 30 bones.
- Q15Which event directly causes the unmasking of active sites on actin during contraction?
- Release of acetylcholine
- Binding of Ca²⁺ to troponin
- ATP binding to the myosin head
- Pumping of Ca²⁺ into the sarcoplasmic reticulum
Answer: (B) Binding of Ca²⁺ to troponin
Ca²⁺ released from the sarcoplasmic reticulum binds troponin, which shifts tropomyosin away and exposes the active sites on actin, allowing cross-bridge formation.
- Q16Match the following and mark the correct option. Column I A. Fast muscle fibres B. Slow muscle fibres C. Actin filament D. Sarcomere Column II i. Myoglobin ii. Lactic acid iii. Contractile unit iv. I-band
- A-i, B-ii, C-iv, D-iii
- A-iii, B-ii, C-iv, D-i
- A-ii, B-i, C-iii, D-iv
- A-ii, B-i, C-iv, D-iii
Answer: (D) A-ii, B-i, C-iv, D-iii
C. Tests: linking each fibre type to its metabolic marker and each filament to the band it builds. Why C: Fast (white) fibres hold little myoglobin and few mitochondria, so they respire anaerobically and accumulate lactic acid, giving A-ii. Slow (red) fibres are packed with myoglobin, the red oxygen storing pigment that supports aerobic respiration, giving B-i. Actin, the thin filament, occupies the light I-band, giving C-iv. The sarcomere, the stretch between two successive Z lines, is the functional contractile unit, giving D-iii. So A-ii, B-i, C-iv, D-iii. Why not A: it hands myoglobin to fast fibres and lactic acid to slow fibres, but myoglobin is the pigment of slow oxidative fibres [misconception A: “fast fibres must store more oxygen”]. Why not B: the two fibre pairings are right, but it calls actin the contractile unit and the sarcomere the I-band; the sarcomere is the unit and actin is what builds the I-band. Why not D: three of its four pairings fail, it calls fast fibres the contractile unit, hands lactic acid to slow fibres and calls the sarcomere myoglobin; only actin with the I-band survives. Remember: red = myoglobin = slow = aerobic, white = lactic acid = fast, and the I-band is actin only.
- Q17Select the correct statements regarding mechanism of muscle contraction. A. It is initiated by a signal sent by CNS via sensory neuron. B. Neurotransmitter generates action potential in the sarcolemma. C. Increased Ca⁺⁺ level leads to the binding of calcium with troponin on actin filaments. D. Masking of active site for actin is activated. E. Utilising the energy from ATP hydrolysis to form cross bridge. Choose the most appropriate answer from the options given below:
- A and D only
- C, D and E only
- B, D and E only
- B, C and E only
Answer: (D) B, C and E only
A. Tests: separating the true steps of contraction from two classic inversions, the neuron type and the masking step. Why A: A is false, the command travels out on a motor (efferent) neuron; sensory neurons carry signals in towards the CNS. B is true, acetylcholine released at the motor end plate depolarises the sarcolemma and generates an action potential. C is true, calcium released from the sarcoplasmic reticulum binds troponin on the thin filament. D is false, that calcium binding unmasks the active site on actin, masking is exactly what calcium removes. E is true, the myosin head hydrolyses ATP and uses the released energy to attach and form the cross bridge. So B, C and E. Why not B: it retains D, but the active site is unmasked once calcium binds troponin, not masked, and it also drops the true statement B about the action potential in the sarcolemma. Why not C: both statements it selects are false, A names a sensory neuron and D reverses the masking step [misconception: “reflex style sensory input drives voluntary contraction”]. Why not D: B and E are true but D is not, so the masking statement spoils the set. Remember: the command leaves the CNS on a motor (efferent) neuron, calcium lands on troponin, the actin site is UNmasked, and ATP powers the cross bridge.
- Q18A chronic autoimmune disorder affecting the neuromuscular junction, leading to fatigue, weakening and paralysis of skeletal muscle, is called:
- Arthritis
- Muscular dystrophy
- Gout
- Myasthenia gravis
Answer: (D) Myasthenia gravis
Myasthenia gravis is an autoimmune disorder in which antibodies block acetylcholine receptors at the neuromuscular junction, causing fatigue and progressive muscle weakness/paralysis. Arthritis and gout affect joints; muscular dystrophy is a genetic muscle degeneration.
- Q19During muscle contraction, which of the following remains UNCHANGED in length?
- Sarcomere
- A-band
- I-band
- H-zone
Answer: (B) A-band
As thin filaments slide inward, the I-band and H-zone shorten and the whole sarcomere shortens, but the A-band (length of the thick filaments) stays constant.
- Q20Long bones function in:
- Support and erythrocyte synthesis only
- Support and erythrocyte & leucocyte synthesis
- Erythrocyte formation only
- Support only
Answer: (B) Support and erythrocyte & leucocyte synthesis
Long bones provide support and, through their bone marrow, produce blood cells – both erythrocytes (RBCs) and leucocytes (WBCs). Options limiting them to support only, or to RBC/erythrocyte formation only, are incomplete.
- Q21What is the type of movable joint present between the atlas and axis?
- Saddle
- Gliding
- Pivot
- Hinge
Answer: (C) Pivot
A. Tests: naming the synovial joint class of the atlanto-axial articulation. Why A: The odontoid process (dens) of the axis projects up into the bony ring of the atlas, and the atlas together with the skull rotates around that peg. Movement is restricted to rotation about a single axis, which is the definition of a pivot joint, and it is what lets you turn your head sideways to say no. Why not B: a saddle joint has reciprocally concave and convex surfaces allowing movement in two axes, and its human example is the carpal to metacarpal joint of the thumb. Why not C: a hinge joint permits flexion and extension in one plane only, as at the knee or elbow, and gives no rotation [misconception C: “any single axis joint is a hinge”]. Why not D: a gliding joint lets flat surfaces slide over one another, as between the carpals, with no axis of rotation at all. Remember: atlas turning on axis is the ‘no’ joint, a pivot.
- Q22Glenoid cavity articulates
- clavicle with scapula
- humerus with scapula
- clavicle with acromion
- scapula with acromion
Answer: (B) humerus with scapula
B. Tests: which two bones the glenoid cavity of the pectoral girdle brings together. Why B: The pectoral girdle on each side is made of a scapula and a clavicle. The glenoid cavity is the shallow, cup shaped depression on the lateral angle of the scapula, and the rounded head of the humerus sits in it. That articulation is the shoulder joint, so the glenoid cavity joins the humerus with the scapula. Why not A: The clavicle does meet the scapula, but at the acromion process, forming the acromioclavicular joint, not at the glenoid cavity [misconception A: “the two bones of the girdle must meet at its only named cavity”]. Why not C: The clavicle meeting the acromion is again the acromioclavicular joint, and it names no role for the glenoid cavity at all [misconception C: “acromion and glenoid cavity are two names for the same socket”]. Why not D: The acromion is itself a process of the scapula, so a scapula to acromion articulation is not a joint between two bones and cannot be what any cavity articulates [misconception D: “the acromion is a separate bone of the shoulder”]. Remember: glenoid cavity takes the humerus, acromion takes the clavicle.
- Q23Match the following columns and select the correct option. Column I (a) Floating ribs (b) Acromion (c) Scapula (d) Glenoid cavity Column II (i) Located between second and seventh ribs (ii) Head of the humerus (iii) Clavicle (iv) Do not connect with the sternum
- (a)-(iv), (b)-(iii), (c)-(i), (d)-(ii)
- (a)-(iii), (b)-(ii), (c)-(iv), (d)-(i)
- (a)-(i), (b)-(iii), (c)-(ii), (d)-(iv)
- (a)-(ii), (b)-(iv), (c)-(i), (d)-(iii)
Answer: (A) (a)-(iv), (b)-(iii), (c)-(i), (d)-(ii)
C. Tests: the anatomy of the last two rib pairs and of the pectoral girdle, matched item by item. Why C: Work each pair. (a) The 11th and 12th rib pairs are called floating ribs precisely because their ventral ends are free and do not connect with the sternum, so (a) goes to (iv). (b) The acromion is the expanded flat process at the top of the scapular spine, and it articulates with the clavicle to form the acromioclavicular joint, so (b) goes to (iii). (c) The scapula is the triangular bone of the dorsal thorax lying between the second and the seventh ribs, so (c) goes to (i). (d) The glenoid cavity is the shallow socket on the scapula that receives the head of the humerus to form the shoulder joint, so (d) goes to (ii). The set (iv), (iii), (i), (ii) is option C. Why not A: It sends floating ribs to the head of the humerus and the glenoid cavity to the clavicle, so both of the shoulder items and the rib item are swapped out of place [misconception A: “the glenoid cavity holds the clavicle”]. Why not B: It pairs floating ribs with the second to seventh rib position, which is the location of the scapula, and pairs the scapula itself with the head of the humerus [misconception B: “floating ribs are the ones behind the shoulder blade”]. Why not D: It pairs the acromion with the head of the humerus, but the humeral head sits in the glenoid cavity, and it leaves floating ribs matched to the clavicle [misconception D: “the acromion is the socket of the shoulder joint”]. Remember: on the scapula, the acromion takes the clavicle and the glenoid cavity takes the humerus.
- Q24Which one of the following is the correct description of a certain part of a normal human skeleton?
- The 9ᵗʰ and 10ᵗʰ pairs of ribs are called the floating ribs.
- Glenoid cavity is a depression to which the thigh bone articulates.
- First vertebra is axis which articulates with the occipital condyles.
- Parietal bone and the temporal bone of the skull are joined by a fibrous joint.
Answer: (D) Parietal bone and the temporal bone of the skull are joined by a fibrous joint.
A. Tests: mapping named skeletal landmarks to the correct joint type and the correct articulating bone. Why A: the parietal and temporal bones meet at the squamous suture, and every suture of the skull is a fibrous joint, held by dense fibrous tissue with no joint cavity and essentially no movement, so A is the only anatomically true statement of the four. Why not B: the first cervical vertebra is the atlas, not the axis, and it is the atlas whose superior facets receive the occipital condyles; the axis is the second vertebra and carries the odontoid process [misconception B: “atlas and axis swapped”]. Why not C: the floating ribs are the 11th and 12th pairs, which have no sternal attachment at all; the 8th, 9th and 10th pairs are false or vertebrochondral ribs that reach the sternum indirectly through the cartilage of the 7th rib [misconception C: “false ribs counted as floating ribs”]. Why not D: the glenoid cavity is the shallow socket of the scapula that receives the head of the humerus, the arm bone; the thigh bone (femur) fits into the acetabulum of the pelvic girdle [misconception D: “glenoid cavity confused with acetabulum”]. Remember: skull bones meet at sutures and every suture is fibrous, and the socket names the girdle, glenoid for the shoulder, acetabulum for the hip.
- Q25Sliding filament theory can be best explained as
- actin and myosin filaments shorten and slide past each other.
- when myofilaments slide past each other, myosin filaments shorten while actin filaments do not shorten
- actin and myosin filaments do not shorten but rather slide past each other
- when myofilaments slide past each other actin filaments shorten while myosin filaments do not shorten
Answer: (C) actin and myosin filaments do not shorten but rather slide past each other
A. Tests: the central claim of the sliding filament theory, that shortening of the muscle is not shortening of the filaments. Why A: In the sarcomere, the myosin heads bind actin, swivel and pull the thin filament towards the centre of the A band, release on binding fresh ATP and repeat. Each cycle drags actin further in, so the overlap increases, the H zone and I band narrow and the sarcomere gets shorter. Neither filament changes its own length at any point, which is why the A band, the length of the thick filament, stays constant throughout. Contraction is sliding, not shrinking. Why not B: Myosin filaments never shorten. If they did, the A band, which is defined by thick filament length, would narrow during contraction, and it is observed to stay the same [misconception B: “the motor filament must contract to pull”]. Why not C: Actin filaments do not shorten either. The I band narrows only because the thin filaments have slid deeper into the A band, not because they lost length [misconception C: “a shrinking I band means shrinking actin”]. Why not D: This claims both filaments shorten, which contradicts the whole theory and again would force the A band to narrow, contrary to observation [misconception D: “everything in a contracting muscle gets shorter”]. Remember: filaments slide, filaments never shrink, and the constant A band is the proof.