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.
It is known as ISCHEMIA.
Ischemia occur when there is an hindrance in the flow of blood to a particular organ in the body. Because it is the blood that carry oxygen round the body, such an organ will not get adequate supply of oxygen. Ischemia is usually caused by blockage or narrowing of the arteries.
Both represent physical weathering.
one reason for the decline inthe population of marine iguqnes is that invasive speciesnare preying upon themvand there eggs hope this helps
Answer:
It will depend on the type of virus that infects the host's cells. For example, if it is a poliovirus, the answer will be <em>"D. poliovirus protein coats and poliovirus genetic material"</em>
Explanation:
A virus is composed of genetic material encapsulated by a protective coat protein (capsid). The genetic material of a virus can be either DNA or RNA and single-strand or double-stranded (either DNA or RNA). Moreover, the capsid may be surrounded by an additional spikey coat known as envelope. During infection, a virus invades the host´s cells to replicate both its genetic material and its proteins (they use host cellular machinery to synthesize new viral proteins). Depending on the type of virus, they can integrate and replicate its genetic material into the host genome (DNA viruses and RNA retroviruses) or replicate its genetic material outside the host genome (RNA viruses in general).
