1. Contraction
2. Actin
3. Tendons
4. Epidermis
5. Dermis
6. Acne
7. A nerve signal from the brain arrives at the intersection of the nerve and muscle cells and releases acetylcholine from the neuron. This triggers chemical changes in the muscle cell involving ions, including Ca2+. Calcium triggers the thick filaments, made of myosin, to attach to the thin filaments, made of actin, in the muscle cell, and the myosin pulls the actin toward the center of the muscle cell. ATP causes the release of the actin fibers, allowing the muscle to relax and the process to begin again.
For Penn Foster.
Answer:
2. Subcutaneous emphysema
Explanation:
Subcutaneous emphysema is a Medical condition where a bulging or swelling occurs beneath the skin due to passage of air or gas in the subcutaneous layer of the skin. Thoracentesis which is mostly done to remove fluid could cause air passage into the subcutaineous tissue resulting in swelling which progresses as more air enters the tissue
Carbon enters the geosphere through the biosphere when dead organic matter (such as peat or marine algae) becomes incorporated into fossil fuels like coal and organic-matter-rich oil and gas source rocks, and when shells of calcium carbonate become limestone through the process of sedimentation briefly described above.
Hope this helps :))
Answer:
The answer is "ligand-gated channel".
Explanation:
The action that is described in the question is an example of a "ligand-gated channel".
The ligand-gated channels are found in the muscles and they are membranes made out of ion-channel proteins which chan be controlled by certain released chemicals into the medium to open them up or closed them and allowing the sodium, potassium or calcium ions to pass through.
I hope this answer helps.
