Workspace Science Test 45
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OFFICIAL ACT Form H31 · December 2024

Science

11 questions ~9 min recommended
00:00
Score
=== Kallar Grass Experiment ===
Kallar grass (a salt-tolerant grass) was planted in a soil having a high salt content. As the roots of the grass grow and release CO2, the soil pH decreases. Ions, such as calcium (Ca2+), from dissolved salts may then be more readily leached (carried downward by water) out of the upper soil layers. Figure 1 and Table 1 show the electrical conductivity (a measure of the number of dissolved ions in the soil that is directly proportional to salt content) and the soil Ca2+ concentration, respectively, for each of 3 soil depths at 5 different times after planting.

=== Rainfall Intensity and Velocity ===
hor-down d velocity is consistent with Student 3’s conclusions? izontal component, v (or v ). Both components are west w constant, and v is parallel to the path.

=== Biodiesel Production ===
Biodiesel is a fuel that is produced when oil from plant sources reacts with ethanol in the presence of a catalyst.

=== Codons and mRNA ===
An mRNA strand contains nucleotides that determine the sequence of amino acids in a protein.

1. Based on Table 1, at 36 months after planting, which soil depth—10 cm or 50 cm—had the lower Ca2+ concentration?

2. Based on Figure 1, the electrical conductivity for a soil depth of 50 cm at 1 month after planting was approximately how much greater than the electrical conductivity for a soil depth of 10 cm at 36 months after planting?

3. According to Table 1, at a soil depth of 50 cm, between which of the following times after planting did the Ca2+ concentration increase?

4. In the study, was electrical conductivity a dependent variable or an independent variable, and was time after planting a dependent variable or an independent variable?

5. For each of the types of SCGs, which of the following statements describes a difference between the oil extraction procedure for the S2 samples and the S3 samples?

6. Suppose that another 50 g sample of Type R SCGs had been tested in the experiment and that the mass of oil extracted had been 2.6 g. The extraction temperature for this sample would most likely have been closest to which of the following temperatures?

7. Before the experiment, a student predicted that, for the Type R SCG samples, the higher the extraction temperature, the greater the percent yield of biodiesel. Do the results of the experiment support the student’s prediction?

8. Which of the nucleobases can be the third nucleobase in a codon for isoleucine?

9. Suppose an mRNA strand contained 4 codons with the nucleobase sequence GCUAUGGCUAAG. What amino acid would be specified immediately after methionine in this strand?

10. In a complementary sequence, nucleobases are swapped such that A becomes U (and vice versa) and C becomes G (and vice versa). Based on this information, which of the following sequences is a complementary sequence for asparagine?

11. Consider the entire outer circle in Figure 1. Serine is specified by how many different codons?