Tissues Derived From Eukaryotic Cells (2A) Practice Test

In an experiment on skeletal muscle repair, researchers compared two grafts implanted into injured muscle: one containing aligned myofibers (multinucleated skeletal muscle cells) and another containing the same cells but randomly oriented. Both grafts were similarly vascularized. After 4 weeks, the aligned graft generated greater unidirectional force along the limb axis during stimulation. Force was measured with a tendon-attached transducer. Which statement best explains the role of tissue organization in the observed functional difference?

A comparative study examined gas-exchange tissue in two vertebrates. Species X has lung tissue with many small alveoli (thin-walled air sacs lined by simple squamous epithelium closely apposed to capillaries). Species Y has fewer, larger air spaces but similar total lung volume. In perfused lung preparations under identical conditions, Species X achieved higher oxygen uptake per minute. No differences in hemoglobin concentration or cardiac output were introduced experimentally. Which statement best explains the role of tissue organization in the observed difference?