Give the best definition of permeability?

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.

Kudzu vines grow by climbing and wrapping around trees. trees covered by kudzu can die because they are starved of sunlight. what type of relationship exists between the trees and the kudzu growing on them?

Everything in the universe originated from a single point. how was it possible for everything in the universe to have occupied a single point in space?