General Science GENETICS IBDP Biology Uncategorized 11.2 Movement June 1, 2021 Shveta 0 Comments Animal Physiology, IBDP Biology, Movement 1.Which processes require calcium? I. Muscle contraction II. Movement of an action potential along an axon III. Production of the skeleton of hard coralsI and II only I and III only II and III only I, II and III 2. What structure is indicated by the arrows? [Source: Courtesy Roger Craig, University of Massachusetts]One muscle fibre One sarcomereOne myofibril One Z line 3. Which structure found in eukaryotes has a single membrane?Nucleus Lysosome Chloroplast Mitochondrion 4. What is the role of calcium in muscle contraction?To release tropomyosin from myosinTo bind to troponin so myosin-binding sites on actin are exposed To bind to tropomyosin so ATP can bind to actin To release ATP from actin so myosin can bind to troponin 5. Which process is part of the mechanism that controls muscle contraction?Troponin enables actin heads to attach to ATP and slide along myosinMyosin heads attach to troponin and tropomyosin pulls on actin filamentsTropomyosin attaches to calcium and breaks the bond between actin and myosinCalcium frees actin filaments for myosin heads to attach6. A skeletal muscle contains bundles of elongated muscle fibre cells. What is the longest structure within each fibre?A myosin filament The sarcomere A myofibril The Z line 7. What is a function of synovial fluid in the elbow joint?Joins the humerus to the radius and ulnaGrows red blood cellsProtects the biceps Allows easy movement8. What is bone X and muscle Y in the diagram of the elbow joint? ABCD9. What is the main role of nerves in human movement?To cause muscles to stretchTo move joints To transport pain signals that indicate muscle injuries To stimulate muscle contraction 10. The following is a diagram of the elbow joint. What structures are indicated by the letters X, Y and Z? ABCD11. Which ions are released from the sarcoplasmic reticulum when a skeletal muscle fibre contracts?Sodium Potassium CalciumChloride 12. What is the role of ATP during contraction of a skeletal muscle fibre?To uncover the myosin binding sites on actin filamentsTo make cross-bridges between actin and myosin filaments To break cross-bridges and re-set myosin heads To cover the myosin binding sites on actin filaments 13. The images below show muscle tissue. Which image shows contracted muscle tissue?I because the dark band is narrower. II because the Z lines are closer together II because there is less overlap between actin and myosinI because the dark bands are darker14. During muscle contraction, what is the role of calcium ions ( Ca2+) which are released from the sarcoplasmic reticulum? To cause ATP hydrolysis on myosin filamentsTo bind to both actin and myosin filaments forming a cross-bridgeTo cause the cross-bridge to detach itself and start a new cycleTo cause binding sites on the actin filaments to be uncovered 15. What is the function of the knee joint?It permits movement in one planeIt allows bones to glide over each otherIt facilitates movement in all planesIt allows a wide range of movement16. What is the function of the synovial fluid in the elbow joint?It removes waste products from the surrounding tissueIt provides glucose and oxygen to the cartilageIt lubricates the joint and prevents frictionIt prevents the bone from becoming brittle17. What is the role of calcium ions during muscle contraction?To block the myosin binding site on actin when the muscle is not contracting To move the molecules blocking the myosin binding site on actinTo form cross-bridges between the actin and myosin filaments To provide the energy for resetting the myosin heads 18. What is the role of ligaments in humans?To hold bones togetherTo hold muscles together To attach bones to muscles To attach nerves to muscles 19. What is the role of ligaments in humans?Linking bones together at a joint Preventing friction at a joint Contracting to move a joint Attaching muscles to bones 20. Which is the sequence of events in muscle contraction? I. Use of ATP II. Formation of cross bridges III. Release of calcium ions from the sarcoplasmic reticulum IV. Actin filament moves towards the centre of the sarcomereI → II → III → IV III → II → IV → I IV → I → II → III II → IV → I → III 21. What is indicated by the letters X, Y and Z? ABCD22. The diagram below shows the side view of the arm joint. Which letter is pointing to the ulna? WXYZ23. What happens during muscle contraction?The number of light bands is reducedThe width of the dark bands is reducedThe lengths of the sarcomeres are reduced. Actin and myosin filaments coil up
