1. The Merkel cells, located in the epidermis, are specialized for:

A. Melanin production
B. Temperature sensation
C. Touch perception
D. Immune defense

Correct answer: C

Rationale: The correct answer is C: 'Touch perception.' Merkel cells, also known as Merkel discs, are found in the skin's epidermal layer and are responsible for sensing touch. These cells are located near nerve endings and help detect light touch and pressure on the skin. They play a crucial role in the perception of tactile sensations and are not involved in melanin production, temperature sensation, or immune defense. Therefore, the specialized function of Merkel cells is primarily related to touch perception, making option C the correct choice.

2. What part of speech is the underlined word in the sentence "I was disappointed by the outcome"?

A. Verb
B. Noun
C. Adjective
D. Adverb

Correct answer: C

Rationale: "Disappointed" modifies the pronoun "I," making it an adjective.

3. Which of the following is NOT a symptom of asthma, a chronic respiratory condition?

A. Wheezing
B. Difficulty breathing
C. Chest tightness
D. Fever

Correct answer: D

Rationale: The correct answer is D: "Fever." Fever is not a symptom commonly associated with asthma. Asthma symptoms typically include wheezing (A), difficulty breathing (B), and chest tightness (C). Wheezing is a high-pitched whistling sound that occurs during breathing, while difficulty breathing refers to the feeling of not getting enough air. Chest tightness is a common sensation of pressure or constriction in the chest. Fever is not a typical symptom of asthma but may occur in other respiratory conditions or infections. Therefore, fever is the correct answer as it does not align with the typical symptom profile of asthma.

4. The microscopic units responsible for muscle contraction are called

A. Neurons
B. Myofibrils
C. Tendons
D. Sarcomeres

Correct answer: D

Rationale: The correct answer is D: Sarcomeres. Sarcomeres are the fundamental contractile units of skeletal muscle. They are composed of overlapping actin and myosin filaments that slide past each other during muscle contraction, resulting in muscle shortening. Neurons (A) are nerve cells that transmit signals to and from the brain. Myofibrils (B) are thread-like structures within muscle fibers that contain sarcomeres. Tendons (C) are fibrous connective tissues that attach muscles to bones, but they are not directly involved in muscle contraction like sarcomeres are.

5. What is the role of surfactant in the respiratory system?

A. To trap dust particles
B. To increase lung compliance
C. To produce mucus
D. To generate oxygen during respiration

Correct answer: B

Rationale: The correct answer is B: 'To increase lung compliance.' Surfactant is a substance produced by the alveolar cells in the lungs that reduces surface tension within the alveoli. This helps to prevent the alveoli from collapsing, making it easier for the lungs to expand and contract during breathing. This action increases lung compliance, which is the ease with which the lungs can be inflated. Trapping dust particles (A) is the role of mucus and cilia in the respiratory system. Surfactant does not produce mucus (C) but rather acts to reduce surface tension. Generating oxygen (D) is the function of the respiratory system as a whole through the process of respiration, and surfactant does not play a direct role in this process.

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.