In the presence of lactose, how long does it take for the lac operon to be expressed? (A) when glucose is more than lactose concentration
(B) when lactose equals glucose concentration
(C) as long as lactose is more than galactose concentration
(D) as long as lactose is more than glucose concentration

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.

The spermists believed that: the male made the only hereditary contribution to the offspring the male and female traits were blended in the offspring the female made the only hereditary contribution to the offspring the male and the female made equal contributions to the next generation

Chitin is a chemical component of the cell walls