Workspace▸ Science▸ Test 8
← Back to Science
Science · Drill 8

Science practice 8

15 questions ~9 min recommended
⏱ 00:00
Score
—
I appreciate your detailed instructions, but I need to clarify an important limitation: **the passage you've provided is primarily scientific data (chemical equations, graphs, and tables) rather than continuous prose text**. The format doesn't contain traditional underlined phrases with standalone digit markers that I can map to your question numbers. The passage consists of: - A chemical equation - Four line graphs (LED Irradiance, CO₂ Concentration, Air Temperature, Relative Humidity) - A data table with plant species and CO₂ exchange rates **There are no visible underlined text segments with question-number markers** in the format you described. This appears to be raw data from a scientific study rather than an ACT English passage with the typical underlined-phrase-per-question structure. To properly render this as HTML with question markers, I would need: 1. The original OCR text showing **where the underlined portions are** (e.g., "carbon monoxide**1**" or similar) 2. Or clarification about which elements of the graphs/tables correspond to which questions **Could you please provide:** - The passage text with embedded question markers (digits) showing exactly where each underlined phrase ends? - Or indicate which graph/table elements correspond to which questions? Once I have that information, I can produce the correctly formatted HTML output.

The leaves of green plants use the energy in sunlight to convert atmospheric carbon into organic carbon through the reactions of photosynthesis. These reactions can be summarized by the following equation:

Gas exchange between the leaf and the environment is an integral part of the photosynthesis reactions. As carbon dioxide enters the leaf, the oxygen produced as a by-product of photosynthesis is released into the environment in a 1:1 ratio. Enclosing a leaf within a lighted chamber allows for the rate of this exchange, and therefore the rate of photosynthesis, to be measured.

Students in a biology class used lighted chambers to measure the photosynthetic rate of leaves from four common plant species: sunflower, water hyacinth, rhoeo, and pothos. A leaf was placed inside the chamber, and a flow of air was introduced. Sensors within the chamber recorded data on light intensity (LED irradiance), carbon dioxide concentration, air temperature, and relative humidity.

The leaf was initially exposed to a constant light intensity of 300 μE/m2/s to stimulate photosynthesis. After this initial period, students incrementally increased the light intensity to investigate the relationship between light intensity and photosynthetic rate.

Figure 2.5 shows the light intensity (LED irradiance) over time for a chamber containing a water hyacinth.

Figure 2.5

Source: "BISC 111/113: Introductory Organismal Biology," by Jocelyne Dolce, Jeff Hughes, Janet McDonough, Simone Helluy, Andrea Sequeira, and Emily A. Bucholtz. http://openwetware.org/wiki/Lab_5:_Measurement_of_Chlorophyll_Concentrations_and_Rates_of_Photosynthesis_in_Response_to_Increasing_Light_Intensity.

Figure 2.6 shows the change in carbon dioxide concentration over time for a chamber containing a water hyacinth.

Figure 2.6

Source: "BISC 111/113: Introductory Organismal Biology," by Jocelyne Dolce, Jeff Hughes, Janet McDonough, Simone Helluy, Andrea Sequeira, and Emily A. Bucholtz. http://openwetware.org/wiki/Lab_5:_Measurement_of_Chlorophyll_Concentrations_and_Rates_of_Photosynthesis_in_Response_to_Increasing_Light_Intensity.

Figure 2.7 shows the change in air temperature over time for a chamber containing a water hyacinth.

Figure 2.7

Source: "BISC 111/113: Introductory Organismal Biology," by Jocelyne Dolce, Jeff Hughes, Janet McDonough, Simone Helluy, Andrea Sequeira, and Emily A. Bucholtz. http://openwetware.org/wiki/Lab_5:_Measurement_of_Chlorophyll_Concentrations_and_Rates_of_Photosynthesis_in_Response_to_Increasing_Light_Intensity.

Figure 2.8 shows the change in relative humidity (RH) over time for a chamber containing a water hyacinth.

Figure 2.8

Source: "BISC 111/113: Introductory Organismal Biology," by Jocelyne Dolce, Jeff Hughes, Janet McDonough, Simone Helluy, Andrea Sequeira, and Emily A. Bucholtz. http://openwetware.org/wiki/Lab_5:_Measurement_of_Chlorophyll_Concentrations_and_Rates_of_Photosynthesis_in_Response_to_Increasing_Light_Intensity.

Students performed 10 light-chamber trials with leaves from each of the four plant species. The carbon dioxide concentration data was then used to calculate the maximum carbon dioxide exchange rate for each leaf.

Table 2.2 shows the calculated and mean carbon dioxide exchange rates for each of the four plant species.

TABLE 2.2 Carbon Dioxide Exchange Rates

Source: http://openwetware.org/wiki/Lab_5:_Measurement_of_Chlorophyll_Concentrations_and_Rates_of_Photosynthesis_in_Response_to_ Increasing_Light_Intensity.

1. The atmospheric carbon absorbed by green plants is in the form of:

2. Which molecule is formed as a by-product of the photosynthesis reactions?

3. According to Figure 2.5, the initial photosynthesis-stimulating period lasted approximately:

4. The slight increase in air temperature indicated in Figure 2.7 is most likely related to the:

5. Sensors within the lighted chamber monitor the presence of which chemical reactant of the photosynthesis reactions?

6. Which graph represents the independent variable in the students' study?

7. Based on the data in Figures 2.5 and 2.6, which light intensity causes a water hyacinth leaf to absorb carbon dioxide at the fastest rate?

8. The data in the table would best support the assertion that sunflower plants:

9. According to Table 2.2, which plant showed the least variability across trials?

10. Based on the information in the passage, if the oxygen concentration within the chamber had been recorded, its graph would most closely resemble which figure?

11. According to the data in Table 2.2, which plant species perform(s) photosynthesis at a faster rate than pothos?

12. Which of the following generalizations is supported by the data in Figures 2.5 through 2.8?

13. Which of the following statements is supported by the data in Table 2.2?

14. Based on the data in Table 2.2, which plant could be expected to be most tolerant of a low-light environment?

15. The passage states that the rates recorded in Table 2.2 represent the maximum carbon dioxide exchange rates observed for each trial. Assuming that light intensity was increased at the same intervals for each trial, at approximately which point during each trial were the exchange rates recorded in the table most likely observed?

← Prev test Next test →
Jump to