PAX Science Practice Test 2022 [PDF] RN NLN & PN Exam

PAX Science Practice Test 2022 [PDF]: National League for Nursing Pre-Admission Exam PAX-RN NLN & PN Science review question answers 2022 & 2023. You can also download printable PDF for better PAX Exam Prep online.

The real NLN PAX Science is a multiple-choice exam with 40 questions in the Science section with a time limit of 35 minutes administered via computer. Candidates can register online through the NLN testing services website.

PAX Science Practice Test

Test Name PAX Practice Test 2022
Purpose Nursing Exam Prep
Test Section Science
Total Questions 30
Question Type Sample multiple choice

Q1. Which statement about white blood cells is true?

  • a. B cells are responsible for antibody production.
  • b. White blood cells are made in the white/yellow cartilage before they enter the bloodstream.
  • c. Platelets, a special class of white blood cell, function to clot blood and stop bleeding.
  • d. The majority of white blood cells only activate during the age of puberty, which explains why children and the elderly are particularly susceptible to disease.
View Correct Answer
Answer Key: A 

Q2. Which locations in the digestive system are sites of chemical digestion?

I. Mouth
II. Stomach
III. Small Intestine

  • a. II only
  • b. III only
  • c. II and III only
  • d. I, II, and III
View Correct Answer
Answer Key: D 

Q3. Which of the following are functions of the urinary system?

I. Synthesizing calcitriol and secreting erythropoietin
II. Regulating the concentrations of sodium, potassium, chloride, calcium, and other ions
III. Reabsorbing or secreting hydrogen ions and bicarbonate
IV. Detecting reductions in blood volume and pressure

  • a. I, II, and III
  • b. II and III
  • c. II, III, and IV
  • d. All of the above
View Correct Answer
Answer Key: D 

Q4. Which of the following structures is unique to eukaryotic cells?

  • a. Cell walls
  • b. Nuclei
  • c. Cell membranes
  • d. Organelles
View Correct Answer
Answer Key: B 

Q5. Which is the cellular organelle used for digestion to recycle materials?

  • a. The Golgi apparatus
  • b. The lysosome
  • c. The centrioles
  • d. The mitochondria
View Correct Answer
Answer Key: B 

Q6. A rock has a mass of 14.3 grams (g) and a volume of 5.4 cm3, what is its density?

  • a. 8.90 g/cm3
  • b. 0.38 g/cm3
  • c. 77.22 g/cm3
  • d. 2.65 g/cm3
View Correct Answer
Answer Key: D 

Q7. Why do arteries have valves?

  • a. They have valves to maintain high blood pressure so that capillaries diffuse nutrients properly.
  • b. Their valves are designed to prevent backflow due to their low blood pressure.
  • c. They have valves due to a leftover trait from evolution that, like the appendix, are useless.
  • d. They do not have valves, but veins do.
View Correct Answer
Answer Key: D 

Q8. If the pressure in the pulmonary artery is increased above normal, which chamber of the heart will be affected first?

  • a. The right atrium
  • b. The left atrium
  • c. The right ventricle
  • d. The left ventricle
View Correct Answer
Answer Key: C 

Q9. What is the purpose of sodium bicarbonate when released into the lumen of the small intestine?

  • a. It works to chemically digest fats in the chyme.
  • b. It decreases the pH of the chyme so as to prevent harm to the intestine.
  • c. It works to chemically digest proteins in the chyme.
  • d. It increases the pH of the chyme so as to prevent harm to the intestine.
View Correct Answer
Answer Key: D 

Q10. Which of the following describes a reflex arc?

  • a. The storage and recall of memory
  • b. The maintenance of visual and auditory acuity
  • c. The autoregulation of heart rate and blood pressure
  • d. A stimulus and response controlled by the spinal cord
View Correct Answer
Answer Key: D 

Q11. Describe the synthesis of the lagging strand of DNA.

  • a. DNA polymerases synthesize DNA continuously after initially attaching to a primase.
  • b. DNA polymerases synthesize DNA discontinuously in pieces called Okazaki fragments after initially attaching to primases.
  • c. DNA polymerases synthesize DNA discontinuously in pieces called Okazaki fragments after initially attaching to RNA primers.
  • d. DNA polymerases synthesize DNA discontinuously in pieces called Okazaki fragments which are joined together in the end by a DNA helicase.
View Correct Answer
Answer Key: C 

Q12. Using anatomical terms, what is the relationship of the sternum relative to the deltoid?

  • a. Medial
  • b. Lateral
  • c. Superficial
  • d. Posterior
View Correct Answer
Answer Key: A 

Q13. Ligaments connect what?

  • a. Muscle to muscle
  • b. Bone to bone
  • c. Bone to muscle
  • d. Muscle to tendon
View Correct Answer
Answer Key: B 

Q14. Identify the correct sequence of the 3 primary body planes as numbered 1, 2, and 3 in the above image.

  • a. Plane 1 is coronal, plane 2 is sagittal, and plane 3 is transverse.
  • b. Plane 1 is sagittal, plane 2 is coronal, and plane 3 is medial.
  • c. Plane 1 is coronal, plane 2 is sagittal, and plane 3 is medial.
  • d. Plane 1 is sagittal, plane 2 is coronal, and plane 3 is transverse.
View Correct Answer
Answer Key: A 

Q15. Which of the following is NOT a major function of the respiratory system in humans?

  • a. It provides a large surface area for gas exchange of oxygen and carbon dioxide.
  • b. It helps regulate the blood’s pH.
  • c. It helps cushion the heart against jarring motions.
  • d. It is responsible for vocalization.
View Correct Answer
Answer Key: C 

Q16. Which of the following is NOT a function of the forebrain?

  • a. To regulate blood pressure and heart rate
  • b. To perceive and interpret emotional responses like fear and anger
  • c. To perceive and interpret visual input from the eyes
  • d. To integrate voluntary movement
View Correct Answer
Answer Key: A 

Q17. What is the major difference between somatic and germline mutations?

  • a. Somatic mutations usually benefit the individual while germline mutations usually harm them.
  • b. Since germline mutations only affect one cell, they are less noticeable than the rapidly dividing somatic cells.
  • c. Somatic mutations are not expressed for several generations, but germline mutations are expressed immediately.
  • d. Germline mutations are usually inherited while somatic mutations will affect only the individual.
View Correct Answer
Answer Key: D 

Q18. A child complains of heavy breathing even when relaxing. They are an otherwise healthy child with no history of respiratory problems. What might be the issue?

  • a. Asthma
  • b. Blood clot
  • c. Hyperventilation
  • d. Exercising too hard
View Correct Answer
Answer Key: A 

Q19. Find the lowest coefficients that will balance the following combustion equation.

__C2H10+__O2→__H2O+__CO2

  • a. 1:5:5:2
  • b. 4:10:20:8
  • c. 2:9:10:4
  • d. 2:5:10:4
View Correct Answer
Answer Key: C 

Q20. What is the purpose of a catalyst?

  • a. To increase a reaction’s rate by increasing the activation energy
  • b. To increase a reaction’s rate by increasing the temperature
  • c. To increase a reaction’s rate by decreasing the activation energy
  • d. To increase a reaction’s rate by decreasing the temperature
View Correct Answer
Answer Key: C 

Q21. Most catalysts found in biological systems are which of the following?

  • a. Special lipids called cofactors.
  • b. Special proteins called enzymes.
  • c. Special lipids called enzymes.
  • d. Special proteins called cofactors.
View Correct Answer
Answer Key: B 

Q22. Which statement is true about the pH of a solution?

  • a. A solution cannot have a pH less than 1.
  • b. The more hydroxide ions in the solution, the higher the pH.
  • c. If an acid has a pH of greater than 2, it is considered a weak base.
  • d. A solution with a pH of 2 has ten times the amount of hydrogen ions than a solution with a power of 1.
View Correct Answer
Answer Key: B 

Q23. Salts like sodium iodide (NaI) and potassium chloride (KCl) use what type of bond?

  • a. Ionic bonds
  • b. Disulfide bridges
  • c. Covalent bonds
  • d. London dispersion forces
View Correct Answer
Answer Key: A 

Q24. Which of the following is unique to covalent bonds?

  • a. Most covalent bonds are formed between the elements H, F, N, and O.
  • b. Covalent bonds are dependent on forming dipoles.
  • c. Bonding electrons are shared between two or more atoms.
  • d. Molecules with covalent bonds tend to have a crystalline solid structure.
View Correct Answer
Answer Key: C 

Q25. Which of the following describes a typical gas?

  • a. Indefinite shape and indefinite volume
  • b. Indefinite shape and definite volume
  • c. Definite shape and definite volume
  • d. Definite shape and indefinite volume
View Correct Answer
Answer Key: A 

Q26. Which of the following areas of the body has the most sweat glands?

  • a. Upper back
  • b. Arms
  • c. Feet
  • d. Palms
View Correct Answer
Answer Key: A 

Q27. A patient’s body is not properly filtering blood. Which of the following body parts is most likely malfunctioning?

  • a. Medulla
  • B. Heart
  • C. Nephrons
  • D. Renal cortex
View Correct Answer
Answer Key: C 

Q28. A pediatrician notes that an infant’s cartilage is disappearing and being replaced by bone. What process has the doctor observed?

  • a. Mineralization
  • b. Ossification
  • c. Osteoporosis
  • d. Calcification
View Correct Answer
Answer Key: B 

Q29. The epidermis is composed of what type of cells?

  • a. Osteoclasts
  • b. Connective
  • c. Dendritic
  • d. Epithelial
View Correct Answer
Answer Key: D 

Q30. Which of the following is directly transcribed from DNA and represents the first step in protein building?

  • a. siRNA
  • b. rRNA
  • c. mRNA
  • d. tRNA
View Correct Answer
Answer Key: C