Which of the following is an example of positive feedback? 1. abscisic acid (aba) in plants slows bud growth in cold temperatures. 2.an increase in ethylene gas causes fruits to ripen more quickly. 3.taking a tranquilizer slows the speed of signal transmission in neurons. 4.panting in dogs increases the amount of cool air in nasal passages and lowers body temperature

What links the two strands in a dna helix together in the middle? a. phosphate groups b. sugar rings bonded together c. proteins d. bases with hydrogen bonds

Match the type of adaptation to the correct example, structural adaptation functional adaptation behavioral adaptation example type of adaptation elephants live in herds to protect their young leaves of a rain forest plant species have a pointed tip that enables rainwater to drain off easily. camels have nostrils that they can close snakes produce venom to kill prey and defend themselves. earthworms coil when touched, as part of a defense mechanism. human skin darkens with increased exposure to sunlight.

All living organisms are composed of a. only one cell. b. at least 100 cells. c. at least three cells. d. one or more cells.