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: D) North Korea
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Explanation:
The United States, the United Kingdom, and France are all countries that have capitalistic economies. This means that (for the most part) private industry and the market determines what products are produced and who gets those products. I said "for the most part" because these countries don't follow a purely capitalistic structure. There are some elements of government regulation to ensure that no breakdowns occur. The regulations are also to ensure some level of fairness as well, in addition to preventing things like fraud.
On the other hand, countries like North Korea are known as command economies because the government determines what products are to be made and they determine who gets the products. This means that they set the prices as well to whatever they feel is correct (even if the market may disagree otherwise). The term "communism" is often strongly connected to the term "command economy".
What the larva and pupa stages have in common is that both stages take place in water.
This is where the insect evolves until it becomes fully grown and then leaves water.
Answer:
I have a chart for this if you'd like that it really helps to better understand the Nitrogen Cycle and how it works.
