3 Aristóteles acreditava que os planetas gi- ravam ao redor do Sol descrevendo órbitas
circulares. Uma das maiores revoluções da
Astronomia moderna, proposta por Kepler
no século XVII, foi a determinação das ór-
bitas elípticas.
Com relação à distância entre o planeta Terra
e o Sol, qual é a principal diferença entre as
órbitas circulares e as órbitas elípticas? Essa
diferença é responsável pelo fenômeno das
estações do ano?

Before the can be observed by using a transmission electron microscope, cells are sliced into very thin sections. what disadvantage does this procedure present in the study of cellular parts

Which of the following describes a negative feedback loop? when the heart rate is too high, the body sends hormones that continually increase the heart rate higher. when a pregnant woman is in labor, the body sends hormones that increase the intensity of contractions, which then increases the secretion of the same hormones. when blood sugar is too low, the body sends hormones that raise blood sugar until it reaches a typical level and hormone secretion slows. when a person is jogging, the body sends hormones that continually decrease the rate of oxygen supply to the legs.

Many body systems work together for proper functioning of the body and to maintain internal homeostasis. the works to break down food eaten before exercising. the takes in the nutrients obtained from the food. the body sweats as a mechanism to cool off, because the is working to flush out toxins.