Like animal hormones, plant hormones:
1. are transported by a circulatory system
2. do not act locally
3. are steroids
4. activate signal transduction pathway

What is incorrect regarding the results of experiments conducted on coleoptiles of canary grass and oats by Charles Darwin and Francis Darwin on phototropism?
1. Both plants grow toward the light source.
2. The tips of coleoptiles were covered with a metal foil and the coleoptiles did not grow toward light.
3. When the metal foil was removed they still not grew toward the light.
4. The growing region of the coleoptiles rather than their tips was covered and the coleoptiles grew toward the light.

In 1913, Peter Boysen-Jensen further developed on the Darwins experiments. Identify the statement that does not relate to his experiments:
1. He cut off the tip of a coleoptile and noticed that it stopped its growth
2. He then separated the tip from the coleoptile with a tiny piece of agar and observed that the coleoptiles grew and curved toward the light.
3. He replaced the agar block with butter and observed that the coleoptiles grew and curved toward the light.
4. He replaced the agar blocks with pieces of Ptatinum foil, and there was no growth.

F. W. Went cut off the tips and placed the cut surfaces onto agar. The tips were removed after an hour and the agar was placed on the cut tips of the coleoptiles grown in the dark. His different experiments and results did not include:
1. Cut off coleoptiles and without agar blocks, did not grow.
2. Agar blocks that contacted cut tips were placed on the center of the cut off coleoptiles and they grew straight up.
3. Agar blocks that did not contact the cut tips of coleoptiles did not show any response.
4. Agar blocks that had contacted the cut tips when placed on one side of the cut off coleoptiles, curved towards the agar blocks.

Generally, plant hormones do not control plant development by affecting:
1. the majorly citric acid cycle and the anabolic Calvin cycle
2. cell division via the cell cycle
3. cell elongation through acid growth
4. mediating short-term physiological responses to environmental stimuli

The practical uses of auxins include:

Plants bend toward light because

The production of which of the following plant hormones by the apical bud of a pine tree inhibits the growth of lateral buds?
1. ABA.
2. cytokinin.
3. gibberellin.
4. auxin.

A plant has been forcibly put into a horizontal position. After some time, the tip of this plant grows:
1. upwards.
2. downwards.
3. straight horizontally.
4. unpredictably.

A piece of parenchyma tissue from a plant is cultured in the absence of cytokinins. The expected result is that:
1. the cells grow smaller with each division.
2. the cells grow very large but do not divide.
3. the cells grow very smalland do not divide.
4. the cells grow large and divide more rapidly than normal.