Roots growing down into the ground are examples of
phototrophism
geotrophism
thigmotrophism
hydrotrophism

Spring tides, when the high tides are at their highest and low tides at their lowest. what is it about these positions that causes these high and low tides?

What is one energy transformation that is taking place in the photo? radiant energy to thermal energy thermal energy to nuclear energy chemical energy to thermal energy radiant energy to chemical energy

Which of the following statements is true about the relationship between genetic variation and natural selection? a. genetic variation must be present in a population before natural selection can act on it. b. genetic variation arises in a population as a result of natural selection. c. natural selection can act on a population whether there is genetic variation within the population or not. d. after natural selection acts on a population, the amount of genetic variation in the population always increases.