C. because stimuli is how your body responds to something, and in this case, someone's heart rate increases WHEN their blood oxygen drop. Do you see how it responds? ;-)
We see the moon because the sun's light reflects off it. So the phases change depending on how much the sun reflects of it. The moon circles around the Earth so at certain times there will be a full moon and at certain times a new moon and everything in between.
I think that since it lives on the ocean floor, at the deepest of the ocean. So anyway, the fin on the Eurypterids is still necessary but not that much, since they live on the ocean floor. Their movements mostly on the ocean floor. So fin would not help them "stick" to the floor. Also there are still gravity acts on the Eurypterids and the feet would help them move faster. Hope this helps.
Some activities that cell requires energy may include cell division, active transport, protein synthesis etc.
In human, Cells get their energy by the food we eat. The nutrients in the food breaks down into soluble and simple molecules in stomach and small intestine and it is absorbed through the small intestine and assimilated into the cells, becoming part of it, providing the uses for each type of nutrient. And of course, many of them is the energy source.
Answer:
objects with more <em><u>mass</u></em> have more gravity
Explanation: