Question 2 : Which of the following is not a biological function of skeleton?

Question 4 : Which of the following are the regulatory protein in the muscle contraction?

Question 6 : Assertion: Thigh muscles can get tired but not the muscles of ventricle of heart. Reason: Muscles of thigh are voluntary whereas that of heart are involuntary muscles.

Question 8 : Statement I : Microtubules are formed only in animal cells.<br>Statement II : Microtubules are made up of a protein called myosin.<br>Choose the correct option.

Question 10 : Which of the following statements about the molecular arrangement of action and myosin in myofibrils is/are incorrect?<br>(i) Each actin (thin filament) is made of 2F (filamentous) actins.<br>(ii) F-actin is the polymer of G (globular) actin.<br>(iii) 2F-actins are twisted into a helix.<br>(iv) Two stands of tropomysion (protein) lie in the grooves of F-actin.<br>(v) Troponin molecurles (complex proteins) are distributed at regular intervals on the tropomyosin.<br>(vi) Troponin forms the head of the myosin molecule.<br>(vii) The myosin is a polymerised protein.

Question 11 : State whether the following statements are true or false.<br/>Actin&#160;is actually a globular protein that assembles as a long beady structure consisting&#160;of two helical chains.

Question 14 : In amoeboid movement, according to Goldacre and Lorsch cytoplasm solates due to

Question 16 : The protoplasmic segment of a striated muscle fibre is termed as

Question 20 : Consider the following four statements (i) - (iv) and select the correct option. <br>(i) Actin is present in thin filament. <br>(ii) H-zone of striated muscle fibre represents both thick and thin filaments.<br>(iii) There are 11 pairs of ribs in man. <br>(iv) Sternum Is present on ventral side of the body.

Question 22 : Assertion: Upon stimulation of a muscle cell, calcium ions $(Ca^{++})$ are released from the sarcoplasmic reticulum. Reason: In recating with a protein complex, $Ca^{++}$ uncover active sites on the actin filaments.

Question 23 : Sarcomere is the functional unit of contraction in a muscle fibre. Identify the portion of myofibril that constitutes a sarcomere<br>

Question 24 : The binding of troponin to calcium in muscle cells exposes the binding site of

Question 27 : Total number of bones in a hindlimb of a man is

Question 28 : Which one of the following is the thick filament of muscle?<br/>

Question 33 : Name the ion responsible for unmasking of active sites for myosin for cross-bridge activity during muscle contraction.

Question 34 : Assertion: &#9; &#9; &#9; &#9; <p>Muscle cells are also called myofibrils.</p> Reason: &#9; &#9; &#9; &#9; <p>Muscle cells are very thin and elongated.</p>

Question 37 : Upon stimulation of skeletal muscles, calcium is immediately made available for binding to troponin from

Question 39 : Cross bridges of sarcomere in skeletal muscle are made up of <br>