Martinez-ENG113 Nursing Assistant. Lippincott | thePoint Free CNA Practice. Annette_Bitups K. PAL 4.0 Part A When a muscle fiber contracts, the I bands diminish in size, the H zones disappear, and the A bands move closer together but do not diminish in length. True False Submit Request Answer

You’ve just tapped into the fascinating world of muscle contraction! This process is guided primarily by the sliding filament theory, which explains how muscle fibers interact during contraction. When a muscle fiber is activated, myosin filaments pull on actin filaments, causing the I bands and H zones to shrink as those filaments slide past each other. However, the overall length of the A bands stays the same, illustrating the dynamism of muscle tissue! To understand this better, think about a classic analogy: A pair of dancers twirling together. They can move closer without changing their individual size, just like the A bands! For anyone preparing for their CNA exams, diving into muscle physiology will not only boost your knowledge but make you more equipped in understanding patient care—after all, a healthy body relies on well-functioning muscles!