Nursing Elites

1. What enzymes do lysosomes contain, leading to their nickname as the cell's 'suicide bags'?

• A. Hydrolytic enzymes
• B. Ligases (bonding enzymes)
• C. Transferases (molecule transfer)
• D. Oxidoreductases (redox reactions)

Correct answer: A

Rationale: Lysosomes are organelles filled with hydrolytic enzymes that break down proteins, nucleic acids, lipids, and carbohydrates. These enzymes aid in digesting cellular waste and foreign substances, hence the term 'suicide bags' due to their involvement in cell degradation and recycling. Ligases are enzymes that catalyze the joining of two large molecules by forming a new chemical bond, not present in lysosomes. Transferases are enzymes that catalyze the transfer of functional groups from one molecule to another, not found in lysosomes. Oxidoreductases are enzymes involved in oxidation-reduction reactions, which are not the primary function of lysosomes.

2. Which hormone is responsible for lowering blood sugar levels?

• A. Glucagon
• B. Insulin
• C. Adrenaline
• D. Cortisol

Correct answer: B

Rationale: Insulin is the hormone responsible for lowering blood sugar levels. It is produced by the pancreas and facilitates the entry of glucose into cells, thereby reducing blood sugar levels. Glucagon, adrenaline, and cortisol have roles in increasing blood sugar levels through various mechanisms. Glucagon raises blood sugar levels by stimulating the liver to release stored glucose, adrenaline increases blood sugar in fight-or-flight responses, and cortisol raises blood sugar levels as part of the stress response. Therefore, in the context of lowering blood sugar levels, insulin is the correct answer.

3. Which of the following nerves has the longest axon in the human body?

• A. Dorsal root ganglion
• B. Laryngeal nerve
• C. Sciatic nerve
• D. None of the above

Correct answer: C

Rationale: The sciatic nerve contains the longest axon in the human body, extending from the lower back down the leg. This nerve is responsible for innervating the muscles of the lower limb. The dorsal root ganglion and laryngeal nerve do not possess axons as long as the sciatic nerve, making them incorrect choices. Therefore, the correct answer is C, the sciatic nerve.

4. Which of the following is NOT a function of the cilia lining the respiratory tract?

• A. Trapping inhaled dust and debris
• B. Moistening inhaled air
• C. Producing mucus
• D. Propelling mucus upwards towards the throat

Correct answer: B

Rationale: The correct answer is B: Moistening inhaled air. The cilia lining the respiratory tract primarily function to trap inhaled dust and debris, produce mucus, and propel the mucus upwards towards the throat for removal. Moistening inhaled air is primarily done by the mucous membranes in the nasal passages, which contain blood vessels that help warm and humidify the air as it passes through the nasal cavity. Therefore, the function of moistening inhaled air is not directly associated with the cilia in the respiratory tract, making it the correct choice in this scenario. Choices A, C, and D are incorrect as they are all functions carried out by the cilia in the respiratory tract.

5. What is the term for a genetic disorder caused by a mutation on the X chromosome?

• A. Autosomal dominant disorder
• B. Autosomal recessive disorder
• C. Sex-linked recessive disorder
• D. Sex-linked dominant disorder

Correct answer: C

Rationale: A genetic disorder caused by a mutation on the X chromosome is termed a sex-linked recessive disorder (Option C). This type of disorder is more commonly seen in males due to their single X chromosome, making them more vulnerable to X-linked mutations. Females have two X chromosomes, providing a protective effect against X-linked disorders.\n- Autosomal dominant disorders (Option A) result from a mutation in one copy of a gene on non-sex chromosomes (autosomes) and are not specifically related to the X chromosome.\n- Autosomal recessive disorders (Option B) occur due to mutations in both copies of a gene on autosomes, not on the X chromosome.\n- Sex-linked dominant disorders (Option D) are rare and lead to more severe symptoms in males as they only require one copy of the mutated gene on the X chromosome to express the disorder. However, this is not the term for a genetic disorder caused by an X chromosome mutation.

Similar Questions