In a forest, what are five biotic factors present? Five abiotic factors?

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.

Suppose you are provided with an actively dividing culture of e. coli bacteria to which radioactive thymine has been added. what would happen if a cell replicates once in the presence of this radioactive base?

Plant species a has a diploid number of 12. plant species b has a diploid number of 16. a new species, c, arises as an allopolyploid from a and b. the diploid number for species c would probably be a) 12. b) 14. c) 16. d) 28. e) 56.