1. Which of the following is NOT a common symptom of pregnancy?

A. Fatigue
B. Nausea
C. Increased urination
D. Loss of appetite

Correct answer: D

Rationale: The correct answer is D: "Loss of appetite." While it is common for pregnant individuals to experience fatigue, nausea, and increased urination due to hormonal changes and the body's adaptations during pregnancy, a loss of appetite is not typically a common symptom. Most pregnant individuals experience increased appetite, particularly in the early stages of pregnancy. This increased appetite is often attributed to the body's need for additional nutrients to support the growing fetus. Therefore, the absence of appetite loss makes option D the correct choice in this question.

2. A medication order is for 250 micrograms of a drug to be administered subcutaneously. The available syringe measures in milliliters. How many milliliters should the nurse draw up?

A. 0.00025 milliliters
B. 0.0025 milliliters
C. 0.025 milliliters
D. 0.25 milliliters

Correct answer: B

Rationale: First convert micrograms to milliliters, knowing 1000 micrograms equal 1 milliliter. Divide the desired dosage (250 micrograms) by the conversion factor (1000 micrograms/milliliter) to find the volume needed: 250 micrograms / 1000 micrograms/milliliter = 0.00025 milliliters. However, drawing such a small volume might be inaccurate, so round to the nearest practical measurement, which is 0.0025 milliliters.

3. Which phenomenon explains the formation of rainbows in the sky?

A. Diffraction
B. Interference
C. Refraction and dispersion of sunlight by water droplets.
D. Reflection from clouds

Correct answer: C

Rationale: Refraction and dispersion of sunlight by water droplets in the atmosphere separate white light into its constituent colors, creating the rainbow phenomenon.

4. What is the difference between active and passive immunity?

A. Active immunity is short-lived, while passive immunity is long-lasting.
B. Active immunity involves the body's own immune response, while passive immunity provides immediate protection through antibodies from another source.
C. Active immunity only protects against bacterial infections, while passive immunity works against both bacteria and viruses.
D. Passive immunity requires repeated vaccinations, while active immunity is a one-time process.

Correct answer: A

Rationale: The correct answer is A: "Active immunity involves the body's own immune response, while passive immunity provides immediate protection through antibodies from another source." Active immunity is long-lasting because it involves the body's immune system producing memory cells that remember specific pathogens, providing long-term protection. Passive immunity, on the other hand, is short-lived as it involves receiving pre-formed antibodies from an external source, such as through maternal transfer or injection of antibodies, which do not create memory cells for long-lasting protection.

5. Positron emission tomography (PET) scans utilize a key property of positrons for medical imaging. What is this property?

A. High mass
B. Positive charge
C. Extreme stability
D. Identical behavior to electrons

Correct answer: B

Rationale: The correct answer is B: 'Positive charge.' Positron emission tomography (PET) scans rely on the fact that positrons are positively charged particles. When a positron is emitted during radioactive decay, it quickly collides with an electron, resulting in annihilation and the release of two gamma rays in opposite directions. These gamma rays are detected by the PET scanner to create detailed images of the body's internal organs and tissues. The positive charge of positrons is crucial for this process to occur, making option B the correct choice.

6. What is the process of converting lactic acid back into pyruvate called?

A. Glycolysis
B. Gluconeogenesis
C. Cori cycle
D. Oxidative phosphorylation

Correct answer: C

Rationale: Rationale: A) Glycolysis is the process of breaking down glucose into pyruvate. B) Gluconeogenesis is the process of synthesizing glucose from non-carbohydrate sources. C) The Cori cycle is the process by which lactic acid produced by anaerobic metabolism in muscles is transported to the liver and converted back into glucose or pyruvate. D) Oxidative phosphorylation is the process by which ATP is synthesized using energy derived from the transfer of electrons in the electron transport chain.