Exam 29: The Working Plant

Which of the following describes a chemical element that a plant must obtain from its environment in order to complete its life cycle?

Experimental plants that were sent up in space shuttle missions did not exhibit all of their normal tropisms.Which of the following responses would you most expect to be lacking from these plants?

A farmer decides she wants to grow certified organic corn and sets out to meet all USDA standards to do so.Her crop grows well for the first 3 years; however,she notices during the 4th and 5th years that plants are getting smaller and producing much less corn.She has not altered farming practices and begins to wonder what is happening.She remembers someone mentioning planting peanuts every 3rd year in place of a corn crop,which leads to much healthier corn.Why would a farmer want to change to a different crop,especially something like peanuts?

-In the figure above,which of the following produce nitrogen in a form that can be used directly by the plant,without need for conversion?

Which of the following is exemplified by a pea tendril contacting a string or wire and coiling around it for support?

Examine the figure below.Which of the following is the site of carbon dioxide uptake by a plant?

Which of the following triggers flowering for plants sensitive to photoperiod?

Which of the following best describes the condition of a twig if the auxin produced by its apical meristem is conveyed equally down all sides?

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

Which of the following weather conditions would cause transpiration to be most rapid?

For plants,mycorrhizae are______.

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?

For a plant,carbon and nitrogen are ________.

Which of the following mechanisms best explains how xylem sap moves up against the downward pull of gravity?

Which of the following statements is TRUE?

Read the following scenario to answer the following questions. 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). -Boysen-Jensen also used the mica to separate a tip of a grass shoot only partially,by cutting the tip halfway and inserting a wafer of mica into the cut.If this experiment supported the Darwins' hypothesis,what would Boysen-Jensen have observed?

Which of the following best describes substances that enter a plant through the root system?

Read the following scenario to answer the following questions. 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 Wents placed his agar blocks only halfway on the cut surfaces of grass shoots with their tips removed,what should he have observed?

What does a plant gain from a mycorrhizal relationship?

Read the following scenario to answer the following questions. 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?