The basic structure of a muscle fiber is comprised of actin and myosin protein chains that straddle each other in a fusiform arrangement. The actin and myosin arrays interlock and move past each other to cause contraction of the muscle. They then move back to their initial positions in relaxation. This gives muscles their elasticity and distensibility. The muscle fibers are bundled, in their 10s to 100s up into myofibrils around an endomysium. Many myofibrils are also bound up in a perimysium to form a muscle fiber.
Answer:
Climate change leads to a loss of species
Global warming resulting from human emissions of greenhouse gases. The consequences include habitat loss; shifts in climatic conditions and in habitats that surpass migrational capabilities; altered competitive relationships.
Explanation:
Answer:
Antibiotic resistance is a consequence of evolution via natural selection. The antibiotic action is an environmental pressure; those bacteria which have a mutation allowing them to survive will live on to reproduce. They will then pass this trait to their offspring, which will be a fully resistant generation.
Survival of the Fittest (Natural Selection):
When bacteria are initially exposed to an antibiotic, those most susceptible to the antibiotic will die quickly, leaving any surviving bacteria to pass on their resistant features to succeeding generations.
Answer:
B. cougar
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