Nursing Elites

1. Which of the following structures in the respiratory system is responsible for gas exchange?

• A. Trachea
• B. Alveoli
• C. Bronchi
• D. Diaphragm

Correct answer: B

Rationale: The correct answer is B: Alveoli. The alveoli in the lungs are responsible for gas exchange. They have a thin membrane that allows for the exchange of oxygen and carbon dioxide between the air in the lungs and the blood in the capillaries surrounding them. This process is essential for respiration, providing oxygen to the body's tissues and removing carbon dioxide, a waste product of cellular metabolism. Choices A, C, and D are incorrect. The trachea is a passageway that carries air to and from the lungs but is not directly involved in gas exchange. Bronchi are airway passages that further divide into smaller bronchioles leading to the alveoli but do not perform gas exchange themselves. The diaphragm is a muscle involved in the breathing process by aiding in inhalation and exhalation, but it is not the structure responsible for gas exchange in the respiratory system.

2. What is a monohybrid cross, and what is the ratio of dominant to recessive gene manifestation?

• A. A cross involving two traits, 9:3:3:1
• B. A cross involving one trait, 3:1
• C. A cross involving two traits, 1:2:1
• D. A cross involving one trait, 1:1

Correct answer: B

Rationale: A monohybrid cross is a genetic cross involving one trait. The ratio of dominant to recessive gene manifestation in the offspring is typically 3:1 when both parents are heterozygous. This ratio is the genotypic ratio, not just the phenotype ratio, where the dominant allele is present in 3 out of 4 offspring, and the recessive allele is present in 1 out of 4 offspring. Choice A is incorrect because it describes a dihybrid cross ratio. Choice C is incorrect as it represents the genotypic ratio for a monohybrid cross involving incomplete dominance. Choice D is incorrect as it does not reflect the typical ratio for a monohybrid cross.

3. Which of the following joints is an example of a hinge joint?

• A. Hip joint
• B. Elbow joint
• C. Shoulder joint
• D. Knee joint

Correct answer: B

Rationale: The correct answer is B: Elbow joint. A hinge joint allows movement primarily in one plane, enabling bending and straightening actions. The elbow joint specifically functions as a hinge joint, facilitating the bending and straightening of the arm. The other options, such as the hip joint (A), shoulder joint (C), and knee joint (D), are not examples of hinge joints as they allow movement in multiple planes with more complex motions.

4. A symbiotic relationship where one organism benefits and the other is not harmed is called:

• A. Mutualism
• B. Commensalism
• C. Parasitism
• D. Predation

Correct answer: B

Rationale: B) Commensalism: In commensalism, one organism benefits while the other is neither helped nor harmed. This is the relationship described in the question. The correct answer is Commensalism because it specifically fits the scenario where one organism benefits without affecting the other. A) Mutualism: In mutualism, both organisms involved benefit from the relationship. C) Parasitism: In parasitism, one organism benefits at the expense of the other organism, which is harmed. D) Predation: In predation, one organism (predator) kills and consumes another organism (prey) for food.

5. Which muscle causes a joint to bend?

• A. Cardiac
• B. Extension
• C. Flexor
• D. Smooth

Correct answer: C

Rationale: The correct answer is C: Flexor. A flexor muscle contracts to bend a joint, such as bending the elbow or knee. Flexor muscles are responsible for flexing or bending a joint, while extensor muscles are responsible for extending or straightening a joint. Choice A, Cardiac, is incorrect as cardiac muscle is found in the heart and is responsible for pumping blood. Choice B, Extension, is incorrect as extension refers to the straightening or extending movement of a joint, which is opposite to bending. Choice D, Smooth, is incorrect as smooth muscles are involuntary muscles found in organs like the intestines and blood vessels, not directly responsible for bending joints.

Similar Questions