Title Locomotion and Movement NEET EX-2 Solution fie.docx.pdf ✅

30 LOCOMOTION AND MOVEMENT EXERCISE – 2: Previous Year Questions 1. Chronic autoimmune disorder affecting neuromuscular junction leading to fatigue, weakening and paralysis of skeletal muscle is (NEET 2021) (a) Myasthenia gravis (b) Gout (c) Arthritis (d) Muscular dystrophy Ans. (a) Sol. Myasthenia gravis is an autoimmune disorder affecting neuromuscular junction leading to fatigue, weakening and paralysis of skeletal muscles. Gout occurs due to accumulation of uric acid crystals which enters into. 2. Match list 1 and list 2 (NEET 2021) Choose the correct answers from the options given below List - I List – II 1. Scapula i. Cartilaginous joints 2. Cranium ii. Flat bone 3. Sternum iii. Fibrous joints 4. Vertebral column iv. Triangular flat bone (a) 1– iv, 2 – ii, 3 – iii, 4 – i (b) 1– iv, 2 – iii, 3 – ii, 4 – i (c) 1– i, 2 – iii, 3 – ii, 4 – iv (d) 1– ii, 2 – iii, 3 – iv, 4 – i Ans. (b) Sol. Scapula is a bone of the pectoral girdle. It is larger than the clavicle and is triangular in shape. Cranium is also called the brain box and is made up of 8 bones joined with fibrous joints. Sternum is also called the breast bone as it is present in the thoracic region forming the ventral portion of the rib cage Vertebral column has intervertebral discs which are joined by cartilaginous joints. 3. During muscular contraction, which of the following events occur. (NEET 2021) 1. ‘H’ zone disappears 2. ‘A’ band widens 3. ‘I’ band reduces in width 4. Myosin hydrolysis ATP releasing ADP and P 5. Z line attaches to actin and pull inwards (a) 2,3,4 and 5 only (b) 2,4,5 and 1 only (c) 1,3,4 and 5 only (d) 1,2,3 and 4 only Ans. (c) Sol. During the contraction of a muscle, the actin filaments are pulled inwards by myosin filaments. The hydrolysis of ATP causes the sliding of actin filament due to which the I band reduces in width. This causes the disappearance of the H zone and pilling of the Z line also. 4. Match the following columns and select the correct option (NEET 2020) Column - I Column – II 1. Floating ribs i. Located between second and seventh rib 2. Acromion ii. Head of humerus 3. Scapula iii. Clavicle 4. Glenoid cavity iv. Do not connect with sternum (a) 1– i, 2 – iii, 3 – ii, 4 – iv (b) 1– iii, 2 – ii, 3 – iv, 4 – i (c) 1– iv, 2 – iii, 3 – i, 4 – ii (d) 1– ii, 2 – iv, 3 – i, 4 – iii Ans. (c) Sol. The 11 th and 12 th rib cage are the floating ribs that do not connect with the sternum. Acromion is a process that is a part of the clavicle. Scapula is a part of the pectoral girdle and extends from the second to seventh rib. Glenoid cavity is located in the head of humerus 5. Match column I and column II and choose the correct option. (NEET 2020) Column - I Column – II 1. Gout i. Decrease level of estrogen 2. Osteoporosis ii. Low Ca 2+ ions in blood 3. Tetany iii. Accumulation of uric acid crystals 4. Muscular Dystrophy iv. Autoimmune disorder v. Genetic disorder
31 LOCOMOTION AND MOVEMENT (a) 1-ii, 2-i, 3-iii, 4-iv (b) 1-iii, 2-i, 3-ii, 4-v (c) 1-iv, 2-v, 3-i, 4-ii (d) 1-i, 2-ii, 3-iii, 4-iv Ans. (b) Sol. Gout occurs due to accumulation of uric acid crystals which enters into blood and cause inflammation of joints also. Osteoporosis is a disease in which bone loses minerals and fibres from its matrix. There are more chances of fractures. Major causative factors are hormonal imbalance like calcitonin from thyroid, sex hormones like estrogen parathormone from parathyroid gland and deficiency of vitamin D and calcium. Muscular dystrophy is a genetic defect in which a muscle protein dystrophin is defective. Tetany is a rapid spasm that occurs due to low Ca 2+ in body fluid. 6. Select the correct option. (NEET 2019) (a) 11 th and 12 th pairs of ribs are connected to the sternum with the help of hyaline cartilage. (b) Each rib is a flat thin bone and all the ribs are connected dorsally to the thoracic vertebrae and ventrally to the sternum (c) There are seven pairs of vertebrosternal, three pairs of vertebrochondral and two pairs of vertebral ribs (d) 8 th , 9 th and 10 th pairs of ribs articulate directly with the sternum Ans. (c) Sol. -Vertebrosternal ribs are true ribs, dorsally they are attached to the thoracic vertebrae and ventrally connected to the sternum with the help of hyaline cartilage. First seven pairs of ribs are called true ribs. -8 th , 9 th and 10 thpairs of ribs do not articulate directly with the sternum but join the seventh rib with the help of hyaline cartilage. These are vertebrochondral or false ribs. -Last 2 pairs (11 th & 12 th) of ribs are not connected ventrally and are therefore called floating ribs. -Only the first seven pairs of ribs are ventrally connected to the sternum. 7. Which of the following muscular disorders is inherited? (NEET 2019) (a) Botulism (b) Tetany (c) Muscular dystrophy (d) Myasthenia gravis Ans. (c) Sol. Muscular dystrophy is a genetic disorder that occurs due to a defect in the gene responsible for the formation of dystrophin protein. Botulism is an infectious disease caused by bacteria Clostridium botulism. Tetany occurs due to low ca 2+ levels in the blood. Myasthenia gravis is an autoimmune disorder 8. Match the following joints with the bones involved. (NEET 2019) Column - I Column – II a. Gliding joint i. Between carpals and metacarpals of thumb b. Hinge joint ii. Between atlas and axis c. Pivot joint iii. Between the carpals d. Saddle joint iv. Between humerus and ulna (a) a-iii, b-iv, c-ii, d-i (b) a-iv, b-i, c-ii, d-iii (c) a-iv, b-ii, c-iii, d-i (d) a-i, b-iii, c-ii, d-iv Ans. (a) Sol. Gliding joint is present between the carpals and also between tarsals. Hinge joint is present between the humerus and ulna forming the elbow joint and also forming the knee joint. Femur joint is present between femur, tibia and patella. Pivot joint is the joint present between atlas and axis. Saddle joint is present between carpals and metacarpals of thumb. 9. Which of the following is an autoimmune disorder? (NEET 2019) (a) Myasthenia gravis (b) Tetany (c) Arthritis (d) Osteoporosis Ans. (a) Sol. Myasthenia gravis is an autoimmune disorder affecting neuromuscular junction leading to fatigue, weakening and paralysis of skeletal muscles. Arthritis is inflammation of joints. . Osteoporosis is a disease in which bone loses minerals and fibres from its matrix Tetany is rapid spasm that occurs due to low calcium level in body fluids. 10. Which of the following hormones play an important role in osteoporosis? (NEET 2018)
64 LOCOMOTION AND MOVEMENT (a) Aldosterone and prolactin (b) Progesterone and aldosterone (c) Estrogen and parathyroid hormone (d) Prolactin and parathyroid hormone Ans. (c) Sol. Osteoporosis is a disease in which bone loses minerals and fibres from its matrix. There are more chances of fractures. Major causative factors are hormonal imbalance like calcitonin from thyroid, sex hormones like estrogen, parathormone from parathyroid gland and deficiency of vitamin D and calcium 11. Calcium is important in skeletal muscle contraction because it (NEET 2018) (a) Detaches the myosin head from the actin filament. (b) Binds to troponin to remove the masking of active site on actin for myosin (c) Prevents formation of bond between myosin cross bridge and actin filaments. (d) Activates myosin ATPase by binding to it. Ans. (b) Sol. Calcium is important in skeletal muscle contraction because it binds to troponin which is a protein complex, to remove the masking of the active site on actin. Muscle contraction plays certain functions in the body, such as posture, joint stability and heat production. Neurons will not be able to release neurotransmitter without calcium 12. The pivot joint between atlas and axis is a type of (NEET 2017) (a) Fibrous joint (b) Cartilaginous joint (c) Synovial joint (d) Saddle joint Ans. (c) Sol. The pivot joint between atlas and axis is a type of synovial joint. Synovial joints are joints that allow movement in various directions. It allows for smooth movements between adjacent bones. The primary movement of the atlantoaxial joint complex is rotation. 13. Out of ‘X’ pairs of ribs in humans only ‘Y’ pairs are true ribs. Select the option that correctly represents values of X and Y and provides their explanation. (NEET 2017) (a) X = 12, Y = 7 True ribs are attached dorsally to vertebral column and ventrally to the sternum (b) X = 12, Y = 5 True ribs are attached dorsally to vertebral column and sternum at the two ends. (c) X = 24, Y = 7 True ribs are dorsally attached to vertebral column but are free on ventral side. (d) X = 24, Y = 12 True ribs are dorsally attached to vertebral column but are free on ventral side. Ans. (a) Sol. Human beings have 12 pairs of ribs but among them only 7 pairs are known as true ribs. This is because only seven pairs of ribs are attached directly to the sternum by costal cartilages. 8 th , 9th and 10 th pairs do not join the sternum directly but are connected to the 7 th rib by cartilage. Hence, they are called false ribs. 11 th and 12 th pair do not articulate with the sternum at all. So, they are called floating ribs. 14. Lack of relaxation between successive stimuli in sustained muscle contraction is known as (NEET 2016) (a) Spasm (b) Fatigue (c) Tetanus (d) Tonus Ans. (c) Sol. Lack of relaxation between successive stimuli in sustained muscle contraction is known as tetanus. Tetanus is a serious disease caused by a bacterial toxin that affects the nervous system, leading to painful muscle contractions. It is also called Lockjaw disease. 15. Name the ion responsible for unmasking of active sites for myosin for cross-bridge activity during muscle contraction. (NEET 2016) (a) Calcium (b) Magnesium (c) Sodium (d) Potassium Ans. (a) Sol. During polarization, calcium is the ion released into the sarcoplasm from the sarcoplasmic reticulum. It attaches to the Troponin-C. Hence, a conformational change is brought in the tropomyosin. Due to this, the unmasking of active sites on actin for myosin binding takes place. Between actin and myosin, cross-bridges are formed which results in muscle contraction. 16. Osteoporosis, an age-related disease of skeletal system, may occur due to (NEET 2016) (a) immune disorder affecting neuromuscular junction leading to fatigue. (b) high concentration of Ca ++ and Na + .
31 LOCOMOTION AND MOVEMENT (c) decreased level of estrogen. (d) accumulation of uric acid leading to inflammation of joints. Ans. (c) Sol. Due to the decreased level of estrogen, bones start becoming weak. This can result in easy breakage of bones. This condition where bones become weak and result in a porous condition of bones is called osteoporosis. Estrogen deficiency results in increased osteoclast formation and enhanced bone resorption. 17. Which of the following is not a function of the skeletal system? (NEET 2015) (a) Locomotion (b) Production of erythrocytes (c) Storage of minerals (d) Production of body heat Ans. (d) Sol. The skeletal system provides shape to the body and structure to the body. Certain bones in the skeleton contain bone marrow which produces red blood cells, white blood cells and platelets. Bones are a storehouse of calcium and phosphorus. But, the skeletal system has no role in the production of body heat. 18. Which of the following joints would allow no movement? (NEET 2015) (a) Ball and Socket joint (b) Fibrous joint (c) Cartilaginous joint (d) Synovial joint Ans. (b) Sol. Fibrous joints are fixed or immovable joints since they do not have the ability to show movement. Fibrous joints are connected by dense connective tissue. It consists mainly of collagen. Example, fibrous joints are present in between the skull bones. 19. Sliding filament theory can be best explained as (NEET 2015) (a) When myofilaments slide pass each other, actin filaments shorten while myosin filaments do not shorten. (b) Actin and myosin filaments shorten and slide pass each other (c) Actin and myosin filaments do not shorten but slide pass each other (d) When myofilaments slide pass each other myosin filaments shorten but actin filaments do not shorten. Ans. (c) Sol. During the muscle contraction, the myofilaments slide pass each other. This sliding involves the shortening of the I band. But ‘A’ band remains unchanged. Similarly, the length of actin and myosin filaments also does not change. 20. Glenoid cavity articulates (NEET 2015) (a) Clavicle with acromion (b) Humerus with acromion (c) Scapula with clavicle (d) Scapula with acromion Ans. (b) Sol. The glenoid cavity is a structural feature on the scapula bone which is also known as shoulder bone. The glenoid cavity of the scapula articulates with the head of the humerus, the upper-arm bone at the shoulder joint, enabling the arm to move relative to the torso. 21. Select the correct matching of the type of the joint with the example in human skeletal system (NEET 2014) Type of Joint Example (a) Cartilaginous joint Between frontal and parietal (b) Pivot joint Between third and fourth cervical vertebrae (c) Hinge joint Between humerus and pectoral girdle (d) Gliding joint Between carpals Ans. (d) Sol. Cartilaginous joints are slightly movable joints. The pivot joint is a rotatory joint. Hinge joints allow movement in one plane only. Gliding joint is the one where articulating bones can slide upon one another. Therefore, the joint between the carpals is definitely a gliding joint 22. Stimulation of muscle fibre by a motor neuron occurs at: (NEET 2014) (a) Myofibril