Free Practice Questions for NLN NEX Exam

Translation is the process by which proteins are synthesized at the ribosome. During this process, the genetic code carried by messenger RNA (mRNA) is read in groups of three nucleotides called codons. Each codon specifies a particular amino acid, which is added to a growing protein chain. Transfer RNA (tRNA) brings amino acids to the ribosome but does not contain the original instructions. Ribosomal RNA (rRNA) forms the structural and functional core of the ribosome, and siRNA is involved in gene silencing rather than protein synthesis. Because mRNA carries the direct genetic instructions copied from DNA during transcription, it is the correct source of information used during translation. The NEX Science section frequently tests understanding of the central dogma of molecular biology: DNA → RNA → protein.

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Lymphatic capillaries are small, thin-walled vessels that collect excess interstitial fluid that is not reabsorbed by blood capillaries. This fluid, now called lymph, is transported through the lymphatic system and eventually returned to the bloodstream. This process helps maintain fluid balance and prevents tissue swelling. Arterioles and venules are part of the blood vascular system, not the lymphatic system. Immune capillaries are not a recognized anatomical structure. The NEX Science exam often tests the relationship between the circulatory and lymphatic systems, emphasizing the role of lymphatic capillaries in fluid regulation and immune defense.

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This question tests calculation of the mean. First, add all the infant weights:

8.5 + 11 + 7 + 5 + 7 + 4.5 + 9 + 8 = 60 pounds.

Next, divide the total by the number of infants: 60 ÷ 8 = 7.5? Recheck carefully: 60 ÷ 8 = 7.5, but reviewing the answer choices and recalculating the sum more carefully:

8.5 + 11 = 19.5

19.5 + 7 = 26.5

26.5 + 5 = 31.5

31.5 + 7 = 38.5

38.5 + 4.5 = 43

43 + 9 = 52

52 + 8 = 60

60 ÷ 8 = 7.5, which corresponds to option C.

This problem tests fractions, percentages, and subtraction of parts from a whole—common NEX skills. First calculate the amount spent on decorations:

1

8

8

1

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of $500 equals $62.50. Next calculate the food cost: 25% is equivalent to 0.25, and 0.25 × 500 = $125. Add these two expenses together: $62.50 + $125 = $187.50. This represents the portion of the budget already allocated. To find the remaining budget for venue and entertainment, subtract this amount from the total budget: $500 − $187.50 = $312.50. Therefore, option A is correct. Option B assumes only one category was subtracted. Option C results from incorrect fraction conversion. Option D represents the amount already spent, not the remainder. NEX questions often require careful step-by-step subtraction after converting fractions and percentages correctly.

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This problem tests fraction-to-percent conversion and rounding, a very common skill on the NEX Math Section. First, simplify the fraction if possible. The fraction 3/15 can be reduced by dividing both the numerator and denominator by 3. This gives 1/5. Simplifying first makes the calculation easier and reduces the chance of errors. Next, convert the fraction to a decimal by dividing the numerator by the denominator: 1 ÷ 5 = 0.2. To convert a decimal to a percent, multiply by 100. Thus, 0.2 × 100 = 20.0%. The question asks for the answer rounded to the nearest tenth place. Since 20.0 already has one decimal place, no additional rounding is needed. Therefore, the correct answer is 20.0%, which corresponds to option A. Option B (0.2%) incorrectly leaves the value as a decimal percent. Option C (5.0%) is a common mistake from dividing 3 by 60. Option D (33.3%) would be correct for 1/3, not 3/15.

This is a medication dosage problem, a critical area on the NEX exam. First determine how many doses are taken in 8 hours. Since the medication is taken every 4 hours, the patient takes 8 ÷ 4 = 2 doses. Each dose is 200 mg, so the total amount taken is 200 × 2 = 400 mg. Next convert milligrams to grams using the given conversion: 1,000 mg equals 1 gram. Divide 400 ÷ 1,000 = 0.4 grams. Therefore, the correct answer is D. Option B represents only one dose. Options A and C are dangerously large and result from incorrect placement of the decimal. The NEX frequently tests safe dosage calculations, so careful unit conversion is essential.

This question tests unit conversion and rate calculation, both of which are essential skills on the NEX Math Section, especially for medication and IV flow problems. First, convert liters to milliliters because flow rates are typically expressed in milliliters per hour. Since 1 liter equals 1,000 milliliters, multiply 0.75 liters by 1,000 to get 750 milliliters. Next, determine the flow rate by dividing the total volume by the total time. The fluid is administered over 3 hours, so divide 750 milliliters by 3 hours. This calculation gives 250 milliliters per hour. Therefore, the correct answer is option C. Option A results from dividing incorrectly, option B reflects underestimation, and option D would be correct only if the volume were larger. NEX exam questions often focus on proper setup of unit conversions before performing calculations. Always convert units first, then divide by time to find a rate.

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This question tests interpretation of scatter plots and correlation. In the graph, the horizontal axis represents hours studied, and the vertical axis represents test scores. As the points move from left to right (indicating more hours studied), the points also tend to move upward (indicating higher test scores). This shows a positive relationship between the two variables. While not every point follows a perfect line, the overall trend clearly indicates that students who studied more hours generally achieved higher test scores. Option B correctly describes this positive correlation. Option A is incorrect because scores are not highest when no studying occurs. Option C is incorrect because there is a visible relationship. Option D describes a negative relationship, which is not shown. On the NEX exam, scatter plots are often used to test understanding of trends rather than exact values, so identifying the overall direction of the data is key.

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The range of a data set is calculated by subtracting the lowest value from the highest value. From the graph, the lowest systolic blood pressure reading appears to be about 125 mmHg, while the highest reading is about 185 mmHg. Subtracting gives: 185 − 125 = 60. Therefore, option B is correct. Option C represents a single high reading rather than a range. Options A and D underestimate the difference. NEX questions involving range require careful identification of extreme values on graphs, so it is important to examine the entire data set, not just the most common values.

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This problem tests understanding of integer subtraction, especially with negative numbers. On the number line, −3 is already below zero. Subtracting 7 means moving seven more units to the left. Starting at −3 and moving left seven spaces results in −10. Another way to think about this is to rewrite the problem as adding a negative number: −3 − 7 is the same as −3 + (−7). When adding two negative numbers, you add their absolute values and keep the negative sign. The absolute values of −3 and −7 are 3 and 7, and 3 + 7 = 10, so the result is −10. Option A is therefore correct. Option B is a common mistake when students subtract absolute values incorrectly. Options C and D are positive and would only occur if the signs were misunderstood. The NEX Math Section frequently includes integer operations to assess number sense and sign awareness.