The thyroid is a butterfly-shaped gland that lies in front of the windpipe (trachea), just below the voice box. The parathyroid glands are four tiny glands located behind the thyroid gland. The parathyroid glands produce a substance (parathyroid hormone) that helps control the amount of calcium in the blood.
<span>The main reason surface area to volume ratio is important to a cell is because the surface area to volume ratio determines the rate at which cells uptake nutrients, liquids or gases. For instance, I have two organisms, A and B. Organism A has a surface area to volume ratio of 6:1, whereas organism B has a surface area to volume ratio of 3:1. As organism A has a greater surface area to volume ratio, it means that organism A will be able to take up nutrients, liquids or gases via diffusion or osmosis at a greater rate than organism B, as it has more surface with which to exchange nutrients, liquids or gases. </span>
<span>a and c could be true
Animals don't have peace treaties with each other and the other two options would both allow a population to increase in size.</span>
Two key characteristics of a good scientific investigation are hypothesis and observation of whatever organism your studying.