When a muscle cell receives a signal from a motor neuron, every sarcomere within that muscle cell is activated. The signal moves from the motor neuron to the muscle cell by crossing the synapse. When acetylcholine binds the sodium enters the T tubules and this causes calcium to be released from the sarcoplamic reticulum. Calcium binds to tropomyosin, which allows actin to bind to myosin and each sarcomere contracts. There is nothing and no way to separate individual sarcomeres. They are all activated together.
<span>A.) it is due mainly to the actions of one species
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The Earth is warmer than in previous natural cycles.
Positive effects of warmer temperatures?
Great tans, more swimming, motivation to get outside and do something instead of playing video games.
Answer:
the environment and how they can help save rainforests.
Restore damaged ecosystems by planting trees on land where forests have been cut down.
Encourage people to live in a way that doesn't hurt the environment.
Establish parks to protect rainforests and wildlife.