Locomotion Movement. Topicwise Solved Previous Year Qs. synthesizes (in adults) the blood and its cells.

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1 208 Locomotion Movement and 1. Extremities of long bones possess cartilage [1989] (a) calcified (b) fibrous (c) elastic (d) hyaline Hyalin Cartilage forms the cushions or pads upon the articular surfaces at the joints of long bones and called articular cartilage. Its role in adult body is to withstand forces of compression and torsion at the joints. 2. A deltoid ridge occurs in [1990] (a) Radius (b) Ulna (c) Femur (d) Humerus A deltoid ridge is present along the ventral side of humerus (bone of upper arm - Brachium) which provides the insertion to muscles. 3. Number of cervical vertebrae in camel is [1990] (a) more than that of rabbit (b) less than that of rabbit (c) same as that of whale (d) more than that of horse All mammals have 7 cervical vertebrae in their neck (it is one of the typical mammalian characters). Though they become long in camel & giraff but the number is 7 only. As whale is also a mammal it also possess the same 7 cervical vertebrae. 4. Long bones function in [1993] (a) support (b) support, erythrocyte and leucocyte synthesis (c) support and erythrocyte synthesis (d) erythrocyte formation Long bones gives us support as well as their bone marrow (the peripheral part) synthesizes (in adults) the blood and its cells. 5. Which ion is essential for muscle contraction? [1994] (a) Na (b) K (c) Ca (d) Cl Movement of Ca 2 + out in sarcoplasmic reticulum controls the making and breaking of actin and myosin complex actomyosin due to which muscle contraction and relaxation takes place. Albert Szent Gyorgyi worked out biochemical events of muscle contraction. 6. Which is part of pectoral girdle? [1994] (a) Glenoid cavity (b) Sternum (c) Ilium (d) Acetabulum Glenoid cavity is a shallow concavity on the lateral side of pectoral girdle in which the head of humerus fits making the shoulder joint. 7. The number of floating ribs in the human body, is [1995] (a) 6 pairs (b) 5 pairs (c) 3 pairs (d) 2 pairs In a human body, there are two pairs of floating ribs. i.e., 11th and 12th pairs. These ribs are not attached to either to sternum or the cartilage of another rib. They protect the kidneys. 8. Total number of bones in the hind limb of man is [1998] (a) 14 (b) 30 (c) 24 (d) 21 Each hind limb contain 30 bones namely 1 femur in the thigh, 1 petala in the knee, 1 tibia and 1 fibula in the lower leg, 7 tarsals

2 209 in the ankle, 5 metatarsals in the sole and 14 phalanges in toes. 9. The lower jaw in mammals is made up of [1998] (a) Mandible (b) Dentary (c) Maxilla (d) Angulars Lower jaw is made of mandible. 10. Which of the following is the contractile protein of a muscle? [1998, 2006] (a) Myosin (b) Tropomyosin (c) Actin (d) Tubulin Actin and tropomyosin are part of thin filaments of skeletal muscle. Tubuline is presents in microtubules. Myosin is muscle protein. 11. Tendon is made up of [1999] (a) adipose tissue (b) modified white fibrous tissue (c) areolar tissue (d) yellow fibrous connective tissue Tendons are made of inelastic white fibrous connective tissue. A tendon (or sinew) is a tough band of fibrous connective tissue that connects muscle to bone or muscle to muscle and is designed to withstand tension. Tendons are similar to ligaments except that ligaments join one bone to another. Tendons and muscles work together and can only exert a pulling force. 12. Ligament is a [1999] (a) modified yellow elastic fibrous tissue (b) inelastic white fibrous tissue (c) modified white fibrous tissue (d) none of these Ligament contain both yellow elastin fibres and collagen fibres. The latter are arranged in a manner to allow for stretching. Ligaments help in binding bone to bones. 13. The joint found between sternum and the ribs in humans is [2000] (a) angular joint (b) fibrous joint (c) cartilaginous joint (d) gliding joint In angular joint articulating surface of one bone is oval and convex whereas that of the other is elliptical and concave, it allows movement only in two directions e.g. Wrist. Fibrous joints are unmovable joints e.g. Sutures of skull. Cartilaginous joints have little motility due to disc of fibrocartilage between the articular ends. In gliding joints articulate end of both the bones are either flat or curved to allow gliding movements. e.g. between carpels and wrist. 14. Which one of the following is a skull bone? [2000] (a) Atlas (b) Coracoid (c) Arytaenoid (d) Pterygoid Atlas is the first cervical vertebra. Coracoid is part of the pectoral girdle. Pterygoid is a small bone articulated with palatine. 15. What is sarcomere? [2001] (a) Part between two H-lines (b) Part between two A-lines (c) Part between two I-bands (d) Part between two Z-lines Darks bands on the myofibril form A-band. Middle part of A-band contains light zones- Hensen line (H-lines). Light band on myofibril is called I-band. Middle part of I- band contains Z-lines. Sarcomere is part between two Z-lines. 16. Which statement is correct for muscle contraction? [2001] (a) Length of H-line decreases (b) Length of A-band remains constant (c) Length of I-band increases

3 210 (d) Length of two Z-lines increase When Ca+ ions combine with troponin contraction of muscles initiates. During Contraction the Z lines come closer together and the sarcomere becomes shorter. The length of A band remains constant. I bands shortens and H-band narrows. 17. What will happen if ligaments are cut or broken? [2002] (a) Bones will move freely at joints (b) No movement at joints (c) Bones will become unfix (d) Bones will become fixed Ligments are specialised connective tissues which connect bones together, hence if they are cut or broken the bone will be come unfixed 18. Which of the following pairs, is correctly matched? [2005] (a) Hinge joint - between vertebrae (b) Gliding joint - between zygapophyses of the successive vertebrae (c) Cartilaginous - skull bones joint (d) Fibrous joint - between phalanges Hinge joint: elbow joint, knee joint, ankle joint, inter phalangeal joint. Gliding joint: Intercarpal joint, intertarsal joint, sternoclavicular joint and joint between pre and post zygapophysis of adjacent vertebra. Fibrous joint (Synarthroses): Joints of cranium - bones. Joints between teeth and Jaw bones. Cartilaginous joint (Amphiarthroses): Joints between mammalian vertebrae and two innominate bones (pubic symphysis). 19. An acromian process is characteristically found in the: [2005] (a) pelvic girdle of mammals (b) pectoral girdle of mammals (c) skull of frog (d) sperm of mammals Each half of pectoral girdle has two bones i.e. clavicle and scapula. A spine like, acromian process is attached to scapula for articulation with clavicle bone. 20. In human body, which one of the following is anatomically correct? [2007] (a) Collar bones - 3 pairs (b) Salivary glands - 1 pairs (c) Cranial nerves - 10 pairs (d) Floating ribs - 2 pairs Floating ribs are 2- pairs (11th and 12th pair) which are not attached to sternum 21. Which one of the following items gives its correct total number? [2008] (a) Floating ribs in humans - 4 (b) Amino acids found in proteins - 16 (c) Types of diabetes - 3 (d) Cervical vertebrae in humans - 8 In a humans total number of ribs are Fourteen (14). These are of three types (1) True ribs-these are 7 in number. (2) False ribs- These are two (2) in number (3) Floating rise-these are 4 in number. 22. Which one of the following is the correct matching of three items and their grouping category? Items Group [2009] (a) ilium, ischium, pubis - coxal bones of pelvic girdle (b) actin, myosin, - muscle proteins rhodopsin. (c) cytosine, uracil, - pyrimidines thiamine (d) malleus, incus, - ear ossicles cochlea The pelvic girdle is formed by two innominate bones consists of three separate bones ilium, ischium and the pubis. 23. Elbow joint is an example of: [2009] (a) hinge joint (b) gliding joint (c) ball and socket joint (d) pivot joint Elbow joint is an example of hinge joint. The elbow is a hinge joint; it can open and close like a door. Hinge joint is a form of diarthrosis (freely movable joint) that allows angular movement in one plane only, increasing or decreasing the angle between the bones e.g. elbow joint, knee joint etc.

4 Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair is not matched. Identify the non-matching pair. Pairs of skeletal parts Category [2011M] (a) Sternum and Ribs Axial skeleton (b) Clavicle and Glenoid Pelvic girdle cavity (c) Humerus and Ulna Appendicular skeleton (d) Malleus and Stapes Ear ossicles Glenoid cavity is found in pectoral girdle. 25. Select the correct statement regarding the specific disorder of muscular or skeletal system :- [2012] (a) Muscular dystrophy - age related shortening or muscles. (b) Osteoporosis - decrease in bone mass and higher chance of fractures with advancing age. (c) Myasthenia gravis - Auto immune disorder which inhibits sliding of myosin filaments (d) Gout - inflammation of joints due to extra deposition of calcium. Major causative factors of osteoporosis are imbalances of hormones like calcitonin of thyroid, parathormone of parathyroids, and sex hormones and deficiencies of calcium and vitamin D. 26. Which one of the following pairs of chemical substances is correctly categorized? [2012M] (a) Calcitonin and thymosin - Thyroid hormones (b) Pepsin and prolactin - Two digestive enzymes secreted in stomach (c) Troponin and myosin - Complex proteins in striated muscles (d) Secretin and rhodopsin - Polypeptide hormones Troponin is a protein which is found on actin filament and myosin protein is found in myosin filament. Both actin and myosin are complex proteins in striated muscles. Thymosin is a hormone secreted by the thymus that stimulates development of T cells. Prolactin is a hormone released by the pituitary gland that stimulates breast development and milk production in women. Rhodopsin, also known as visual purple, is not a hormone. It is a biological pigment in photoreceptor cells of the retina that is responsible for the first events in the perception of light. 27. The characteristics and an example of a synovial joint in humans is: Characteristics Examples [NEET 2013] (a) Fluid filled between Skull bones two joints, provides cushion (b) Fluid filled synovial Joint between cavity between two atlas and axis bones (c) Lymph filled between gliding joint two bones, limited between movement carpals (d) Fluid cartilage Knee joint between two bones, limited movements Synovial joints are characterised by the presence of a fluid filled synovial cavity between the articulating surfaces of the two bones. Such an arrangement allows considerable movement. These joints help in locomotion and many other movements. Ball and socket joint (between humerus and pectoral girdle), Hinge joint (knee joint), Pivot joint (between atlas and axis), Gliding joint (between the carpals) and Saddle joint (between carpal and metacarpal of thumb) are some examples. 28. Select the correct statement with respect to locomotion in humans: [NEET 2013] (a) Accumulation of uric acid crystals in joints causes their inflammation (b) The vertebral column has 10 thoracic vertebrae. (c) The joint between adjacent vertebrae is a fibrous joint (d) The decreased level of progesterone causes osteoporosis in old people Vertebral column has 12 thoracic vertebrate. The joints between adjacent vertebrae is cartilaginous joint which permits limited movements. Progesterone is secreted by corpus luteum which supports in pregnancy in females. 29. The H-zone in the skeletal muscle fibre is due to: [NEET 2013]

5 212 (a) The central gap between myosin filaments in the A-band. (b) The central gap between actin filaments extending through myosin filaments in the A-band (c) Extension of myosin filaments in the central portion of the A-band. (d) The absence of myofibrils in the central portion of A-band. Central part of thick filament, not overlapped by thin filaments is called the H zone. H zone is also called Hensen s Line. pulled inwards thereby causing a shortening of the sarcomere, i.e., contraction. It is clear from the above steps, that during shortening of the muscle, i.e., contraction, the I bands get reduced, whereas the A bands retain the length. : Select the correct statement with respect to disorders of muscles in humans [NEET Kar. 2013] (a) Rapid contractions of skeletal muscles causes muscle dystrophy (b) Failure of neuromuscular transmission in myasthenia gravis can prevent normal swallowing (c) Accumulation of urea and creatine in the joints cause their inflammation (d) An overdose of vitamin D causes osteoporosis Myasthenia gravis is a chronic autoimmune muscular disease. It causes breakdown of neuromuscular junction due to which the brain loses control over muscles. The symptoms may include drooping eyelids, difficulty in swallowing muscle fatigue, difficult breathing and inability to control facial expressions. 31. During muscle contraction in humans the [NEET Kar. 2013] (a) Actin filaments shorten (b) Sarcomere does not shorten (c) A band remain same (d) A, H and I bands shorten Increase in Ca++ level into the sarcoplasm leads to the binding of calcium with a subunit of troponin on actin filaments and there by remove the masking of active sites for myosin. Utilising the energy from ATP hydrolysis, the myosin head now binds to the exposed active sites on actin to form a cross bridge. This pulls the attached actin filaments towards the centre of A band. The Z line attached to these actins are also