Arrange the steps in the correct order to explain how a muscle fiber contracts. Myosin and actin protein filaments attach to eac
h 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 nerve impulse reaches the neuromuscular junction.
↓
Calcium ions release into the myofibrils.
↓
Myosin and actin protein filaments attach to each other.
↓
Myosin filaments pull on the actin filaments.
↓
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.
All modern classification systems have their roots in the Linnaean classification system. The Linnaean system is based on similarities in obvious physical traits. It consists of a hierarchy of taxa, from the kingdom to the species. Each species is given a unique two-word Latin name.
protons, neutron, and electrons. Each of these parts has an associated charge, with protons carrying a positive charge, electrons having a negative charge, and neutrons possessing no net charge.
Voyager 1 is the farthest human-made object from Earth, NASA launched it on September 5, 1977, and as of October 2019, it had traveled 13.7 billion miles from the planet. Voyager 1 is believed to have left the solar system in 2012 and is set to encounter its target star AC +79 3888 in about 40,000 years.
