A. Water being pumped in and out of guard cells.
D both a and c sounds correct
D) allele frequencies of some traits change in the population
Alleles can be phenotype (how they appear) and natural selection is when an organism changes in a way that helps them survive.
It can be the way their beaks are formed that gives them a better chance of catching food among other stuff (Darwin's investigation)
Or how they change their color to adapt to the sudden change in tree coloration (Pepper moths)
Answer:
1 and 3
Explanation:
Magnetic waves always go from north to south. So judging by the arrows you can tell the left/yellow pole is the north one. And since that is the north one, the green/right one is the south pole.
