Duchenne Muscular Dystrophy Biological & Biomedical Sciences Essay (Essay Sample)

Duchenne Muscular Dystrophy
1 The gene that is mutated in DMD gives rise to a protein which is important to the function of all striated muscle. Which type(s) of muscle would be affected in a patient with DMD?
Typically, the affected muscles are: shoulder and upper arm muscles, pelvis muscles, and muscles of the things and hips.
2 All three types of muscles contain myofilaments which slide against each other to contract the muscle. What protein composes the thick filaments? What protein composes the thin filaments? With which myofilament is troponin associated?
The thick filaments are composed of myosin. The thin filaments are composed of fibrous actin. Troponin is associated with thin filaments.
3 What is the role of calcium in the muscle contraction? (What does calcium do and why is necessary in muscle contraction?)
The muscle contraction is triggered by calcium. It binds the troponin complex causing myocin bounds along with actin strands to shift positions. Without calcium the contraction would not be smooth.
4 The nerves that control muscles are usually not affected in DMD. What neurotransmitter is released by motor neurons?
Motor neurons release acetylcholine, a small transmitter.
5 What is a motor unit? Which would contain the larger motor units: David’s semimembranosus or his buccinators?
Each muscle is organized in motor units. Each motor unit is made of a motor neuron and the skeletal muscle fiber innervated by this neuron. The larger motor units are in the semimembranosus.
6 As the disease progresses, David may require a ventilator to assist in breathing. Identify the muscle which contributes most to ventilation (moving air in and out of the lungs). What type of muscle is it?