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1. What do you think red muscle is best used for?
Answer: Red muscle is designed for postural function or sustained activity.
2. What do you think the white muscle is best used for?
Answer: White muscle is better suited for sudden and intermittent contraction as it depends on anaerobic respiration.
3. Why do you think healing is slow following Achilles tendon rupture?
Answer: Tendons are cylindrical structures of poorly vascularised, tightly packed collagen fibres with intervening scanty fibrocytes. This relatively poor blood supply results in slow healing.
4. Which activity would be more likely to create an oxygen debt: swimming laps or lifting weights?
Answer: Swimming laps.
5. Which type of muscle fibre would you expect to predominate in the large leg muscles of someone who excels at endurance activities, such as cycling or long-distance running?
Answer: Type 1, slow-twitch fibres
6. Explain how bones detect if they are undergoing mechanical or pathological stress.
Answer: Osteocytes are mechanosensory cells that detect mechanical stress and send messages through their cytoplasmic processes to stimulate osteoblasts to start the process of remodelling. During the immobilisation stage of a healing fracture osteoblasts migrate to repair the defect by laying down new bone matrix, but at the same time bone mass is lost due to limited physical activity.
7. Explain what happens to the bones of astronauts if they stay in the Space Station for a year.
Answer: Bone mass would be lost due to lack of exercise and relative immobility as a result of weightlessness.
8. What is the role of calcium as it relates to the skeletal system.
Answer: Calcium makes bone hard, enabling it to function as a rigid lever.