Exam 29: The Working Plant

-Scientists can now measure phloem pressure directly. Which measurements from a plant, as represented by the figure, would support the pressure flow mechanism of plant transport?

Across the globe, billions of people eat rice. In order to make rice grains (the seed), a rice plant must flower and be pollinated. Rice plants flower only after days become shorter (i.e., summer to autumn). What is the best classification for rice?

The figure shows plants grown in the dark, and illustrates ________ in plants.

The three most important nutrients contained in fertilizers are ________.

A farmer applies an organic fertilizer to her apple trees. Does this practice allow her to sell her apples as certified organic?

-What plant nutrients are shown in the figure?

In a strawberry plant in the summer, the leaves are ________ and the strawberry fruits are ________.

Root nodules in plants such as peas and beans are advantageous because they ________.

What converts soil ammonium to nitrate?

Examine the figure. Where is the site of carbon dioxide uptake by a plant?

Transpiration is ________.

What happens in a twig if the auxin produced by its apical meristem is conveyed equally down all sides?

The figure shows plants originally grown in the dark, and then a light is added on one side only (arrow). Predict the response of the plants to the addition of the light source.

What best describes the opening and closing of the stomata in most plants?

Scenario In the late 1800s, Charles Darwin and his son Francis conducted the first experiments on phototropism. Several years later, their work was furthered by Peter Boysen-Jensen, Arpad Paal, and Frits Went. Peter Boysen-Jensen separated the tip of grass shoots from the rest of the plant using either tiny blocks of agar (a gelatin)or a mica wafer (an impervious rock). Like the Darwins, Boysen-Jensen noticed that the grass did not grow toward a light without its tips. However, when he separated the tip from the rest of the plant using agar, the grass would grow toward a light. The grass would not grow toward a light if the tip of the shoot was separated using a mica wafer. Arpad Paal cut off the tips of grass shoots that were growing in the dark. He placed these cut tips back on the shoots, but with only part of the tip covering the cut surface, and found that the plants grew, in the dark, in the opposite direction from the side with the tip covering it. Lastly, Frits Went removed the tips of many grass shoots and placed them on a large block of agar for a few hours. Then, he cut up the agar block, and was able to make grass shoots without any tips at all grow toward a light by putting these agar blocks on the cut surfaces of the shoots (i.e., no tips were placed back on the shoots, only the agar). -Considering the experiments of the Darwins, Boysen-Jensen, Paal, and Went, what do you conclude about phototropism?

In phytoremediation after a nuclear power plant accident, plants are used to remove ________ and ________ from the soil.

This figure shows a typical label for fertilizer. What fertilizer is contained in this bag?

Scenario In the late 1800s, Charles Darwin and his son Francis conducted the first experiments on phototropism. Several years later, their work was furthered by Peter Boysen-Jensen, Arpad Paal, and Frits Went. Peter Boysen-Jensen separated the tip of grass shoots from the rest of the plant using either tiny blocks of agar (a gelatin)or a mica wafer (an impervious rock). Like the Darwins, Boysen-Jensen noticed that the grass did not grow toward a light without its tips. However, when he separated the tip from the rest of the plant using agar, the grass would grow toward a light. The grass would not grow toward a light if the tip of the shoot was separated using a mica wafer. Arpad Paal cut off the tips of grass shoots that were growing in the dark. He placed these cut tips back on the shoots, but with only part of the tip covering the cut surface, and found that the plants grew, in the dark, in the opposite direction from the side with the tip covering it. Lastly, Frits Went removed the tips of many grass shoots and placed them on a large block of agar for a few hours. Then, he cut up the agar block, and was able to make grass shoots without any tips at all grow toward a light by putting these agar blocks on the cut surfaces of the shoots (i.e., no tips were placed back on the shoots, only the agar). -If Paal grew his plants using a light source that was directly overhead, what should he have observed?

A location in a plant where sugar is being received for storage or consumption is ________.

-Examine the figure. Why does the shoot bend toward the light?