Pass the NLN Nursing Education Program NEX Questions and answers with CertsForce

Mitochondria are responsible for cellular respiration, which occurs in both plant and animal cells. Chloroplasts carry out photosynthesis and are found only in plant cells. Therefore, only plants can perform photosynthesis, while both plants and animals can perform cellular respiration. This distinction is a core concept in cell biology and is frequently tested on the NEX Science exam.

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This question tests measurement interpretation using an ocular micrometer, a skill often assessed on the NEX Science exam. An ocular micrometer is a scale placed in the eyepiece of a microscope and must be interpreted based on the given scale value. In this problem, each division equals 25 micrometers. By carefully counting the number of divisions spanned by the oval in the image, the oval covers8 divisions. To find the total length, the number of divisions is multiplied by the micrometer value per division: 8 × 25 micrometers = 200 micrometers. The other answer choices represent common calculation errors, such as counting too few or too many divisions or using an incorrect multiplication factor. The key to these questions is slow, accurate counting and correct unit conversion. The NEX exam frequently includes microscopy-based questions to assess practical lab interpretation skills.

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Region 4 in the diagram corresponds to the large intestine. The primary function of the large intestine is the absorption of water and electrolytes from undigested food material. This process helps concentrate waste material into feces before elimination. Assimilation of fatty acids and synthesis of triglycerides occur primarily in the small intestine, especially within intestinal epithelial cells. Hydrolysis of proteins occurs mainly in the stomach and small intestine through the action of enzymes such as pepsin and proteases. The NEX Science exam often tests digestive system function by matching specific organs to their primary processes. Since water absorption is the defining function of the large intestine, option B is correct.

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This question tests understanding of the law of superposition, a fundamental principle in geology that is frequently tested on the NEX Science exam. The law of superposition states that in undisturbed sedimentary rock layers, the oldest layers are found at the bottom, while the youngest layers are found at the top. In the table shown, the soil surface is at the top, followed by Fossil D, Fossil C, Fossil B, and Fossil A at the bottom. Because Fossil A is located in the lowest rock layer, it must be the oldest fossil. Fossils found in higher layers were deposited more recently. The key word in the question is “undisturbed,” which means the layers have not been mixed or overturned by geological processes. The NEX exam often emphasizes recognizing this clue to correctly apply the law of superposition. Therefore, Fossil A is the correct answer because it represents the earliest life form preserved in the rock strata.

The pancreas produces insulin, which regulates blood glucose levels. Without insulin, glucose cannot efficiently enter cells, leading to hyperglycemia. Removing the pancreas would therefore cause blood glucose levels to rise. This concept is directly related to diabetes physiology and is a common topic on the NEX Science exam.

This question tests understanding of predator–prey relationships, a key ecology concept on the NEX Science exam. Wolves are the natural predators of moose on Isle Royale. When the moose population was initially high, there was an abundant food supply for wolves. This allowed the wolf population to increase significantly. As the number of wolves increased, predation pressure on the moose population also increased, leading to a sharp decline in moose numbers. This inverse relationship between predator and prey populations is a classic ecological pattern. There is no evidence in the question to suggest disease, human hunting, or breeding rate differences as the primary cause. Instead, the changes in population sizes are best explained by increased predation. The NEX often assesses whether students can interpret real-world ecological data and recognize how population dynamics are influenced by natural predator–prey interactions.

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This question tests percent decrease, a common NEX topic. First find the amount of decrease: 50 mg − 40 mg = 10 mg. Next divide the decrease by the original amount:

10 ÷ 50 = 0.2.

Convert the decimal to a percent by multiplying by 100:

0.2 × 100 = 20%.

Therefore, the correct answer is B. Option D represents the numerical decrease without considering the original value. Option A and C result from incorrect division. On the NEX exam, percent change problems always use the original value as the denominator.

This question tests understanding of standard deviation as a measure of variability. The group with thesmalleststandard deviation has the least variability. Comparing the values, Group 3 has the smallest SD at 6.9. Therefore, option D is correct. The mean does not affect variability; only the SD matters in this comparison. The NEX often includes questions where students must interpret statistical summaries rather than perform calculations. Remember that lower SD values indicate data points are more closely clustered around the mean.

This question combines fractions of time and military time. One full day is 24 hours. One-third of a day equals 24 ÷ 3 = 8 hours. Add 8 hours to 9:15 a.m. Doing so results in 5:15 p.m. In military time, p.m. hours are converted by adding 12 to the hour: 5:15 p.m. becomes 17:15. Therefore, option A is correct. Option C would represent noon, and option D is early morning. The NEX often tests time interpretation, so remembering that military time does not use “a.m.” or “p.m.” is critical.

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This equation involves a mixed number and rounding. First convert the mixed numberinto a decimal. Five divided by eight equals 0.625, so the mixed number becomes 2.625. The equation now reads:

2.625y + 0.25 = 64.

Subtract 0.25 from both sides to isolate the term with y:

2.625y = 63.75.

Next, divide both sides by 2.625:

y ≈ 24.2857.

The question asks for the answer rounded to the nearest tenth. Rounding 24.2857 gives 24.3. Therefore, option A is correct. NEX math questions frequently combine fractions, decimals, and rounding, so converting to decimals early helps reduce errors.

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