1.Choose the correct answer: 1. … are periodic repeated changes in living systems, cyclic processes.
a) photoperiodism b) biorhythms c) taxis
2. …. is physiological reaction of organisms to the length of day or night.
a) photoperiodism b) tropism c) taxis
3. Sunlight provides the alternation of life processes:….
a) bud blossoming b) flowering
c) ripening of fruit d) all three
4. Cocklebur is …..
a) plant of a long day b) plant of a short day
5. Cocklebur starts blooming when the day light period is ……. hours.
a) 12 b) 18 c) 21

Tanya5463    1   27.01.2021 08:26    0