Https://www.ncbi.nlm.nih.gov/pubmed/8300084
This might help
Answer:
1) Organisms in this level are either unicellular or colonial (Cellular level).
2) Organisms that live in a group called a colony (Colonial).
3) The work being divided up into specialized tasks (Division of labor).
4) A very long, contracting cell (Fiber).
5) A group of tissues working together as a unit (Organ).
6) A degree of organism complexity. Organisms at this level have their cells arranged into organs (Organ level).
7) The highest level of complexity of a living thing (Organism level).
8) The limiting of the function of a cell to a specific function muscle (Specialization).
9) A group of organs working together for a common purpose (System).
10) Organisms at this level have their cells arranged into systems (System level).
11) Cells working together to perform a particular task division of labor (Tissue).
12) Organisms at this level have their cells arranged into tissues (Tissue level).
They form a complex called chromatin
Answer:
1. Acetylcholine binds to receptors on the motor end plate
2. Ligand-gated channels open leading to depolarization
3. End plate potential triggers an action potential
4. Transverse tubules convey action potentials into the interior of the muscle fiber
5. Calcium is released from the sarcoplasmic reticulum
6. Calcium ions bind to troponin, which then moves tropomyosin
Explanation:
Acetylcholine (ACh) is a signaling molecule (neurotransmitter) that binds to receptors on muscle cells. This binding triggers the opening of ligand-gated sodium channels, thereby ions enter into muscle cells, which causes the depolarization of the sarcolemma and thus promotes the release of Ca2+ ions from the sarcoplasmic reticulum. The myoneural junction, also known as the motor endplate, is the site of synaptic contact between a motor axon and a skeletal muscle fiber. The endplate potential is the voltage that produces the depolarization of muscle fibers when ACh molecules bind to their receptors in the cell membrane. This depolarization spreads in the sarcolemma through transverse tubules (T tubules) and thus generates an action potential. Finally, this action potential induces the release of Ca2+ in the sarcoplasmic reticulum, which activates troponin protein and induces muscle contraction.
A
Why?:
because i was asking myself what else would make a abyssal plain? and i decided it was a, i WAS gonna say D but i thought really hard about it (plz mark me brain list if it's right is not it's okay and i hope i'm right!) :3