Answer:
C. but the relative amounts of G+C and A+T vary by species.
The bands of circular muscle structures that are located at the cuttlefish skin are most likely responsible for the changes of its outer covering. In addition, the colour cells that are present on the cuttlefish skin were estimated to be about 10 million which is why it was coined "the chameleons of the sea."
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. no one knows for sure
Explanation:
The universe is infinitely big. It goes on forever and ever, so no one knows what's in it. We might find something really big, but we'll never know if there's something even bigger out there.
