What stimulates the pollen tube to grow

The following image is of a diatom. it lives in water and gets food from photosynthesis. it is encased in a hard shell made of something similar to glass or sand . a diatom is a(n) because it has a) multi-celled organism; specialized parts. b) vertebrate; a skeleton. c) insect; an exoskeleton. d) single-called organism; only one cell.

In german cockroaches, curved wing (cv) is recessive to normal wing (cv+). bill, who is raising cockroaches in his dorm room, finds that the frequency of the gene for curved wings in his cockroach population is 0.6. in his friend joe’s apartment, the frequency of the gene for curved wings is 0.2. one day joe visits bill in his dorm room, and several cockroaches jump out of joe’s hair and join the population in bill’s room. bill estimates that, now, 10% of the cockroaches in his dorm room are individual roaches that jumped out of joe’s hair. what is the new frequency of curved wings among cockroaches in bill’s room? 0.69 0.4 0.5 0.31 0.20

Which of the following would be an important part of a multi-step plan to restore the stability of the red-cockaded woodpecker's ecosystem?