During the contraction of a vertebrate skeletal muscle fiber, calcium ions . bind with troponin, causing its shape to change so that the myosin-binding sites on actin are exposed break cross-bridges by acting as a cofactor in the hydrolysis of ATP transmit action potentials from the motor neuron to the muscle fiber spread action potentials through the T tubules

In 2015, about ten percent of total u.s. energy consumption was from renewable energy sources. renewable energy plays an important role in reducing greenhouse gas emissions. when renewable energy sources are used, the demand for fossil fuels is reduced. sanjay and his family want to cut back on their use of non-renewable resources at home. they are thinking of an alternate way to heat their home without adding more greenhouse gases or pollutants to the environment. which renewable resource would not fit into their plan? a) solar power b) burning wood c) constructing a wind turbine eliminate d) generating hydroelectric power