Arrange the steps in the correct order to explain how a muscle fiber contracts. myosin and actin protein filaments attach to each other. calcium ions release into the myofibrils. myosin filaments pull on the actin filaments. the nerve impulse reaches the neuromuscular junction. the motor neuron carries the nerve impulse. the sarcomere shortens.

The motor neuron carries the nerve impulse.

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The nerve impulse reaches the neuromuscular junction.

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Calcium ions release into the myofibrils.

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Myosin and actin protein filaments attach to each other.

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Myosin filaments pull on the actin filaments.

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The sarcomere shortens.

The neurotransmitter (ACh) from motor neurons signals a muscle fiber to depolarize. The depolarization (Na+) will trigger Ca++ release and will initiate contraction by binding to troponin. Myosin pulls the actin strands. ATP sustains the contraction.

what in the weirdo : o

the correct answer is - d. china has a large and growing population.

the fact that china has a large (the biggest) population, and it is still growing, doesn't hinder the agriculture production in the country. in fact, it can for increased production in the agriculture, since there's more labor force, as well the sheer mass of people produces lots of scientists that come up with new inventions as to how to improve this sector. nice example is the inner mongolia region in china, in general dominated by the gobi desert, but few scientist came up with a nice idea as to how to make the region productive by using plants that are very resistant to droughts, so lots of people have been employed, and the region is becoming greener and greener each year, and the production of food in this region is also increasing.