Nursing Elites

1. During gas exchange in the alveoli, what happens to oxygen?

• A. Oxygen is released from the alveoli into the bloodstream.
• B. Oxygen is absorbed from the alveoli into the bloodstream.
• C. Oxygen is converted into carbon dioxide.
• D. Oxygen is stored in the alveoli for later use.

Correct answer: B

Rationale: During gas exchange in the alveoli, oxygen is absorbed from the alveoli into the bloodstream. This process occurs due to the difference in partial pressures of oxygen between the alveoli and the bloodstream, causing oxygen to move from an area of higher concentration (alveoli) to an area of lower concentration (bloodstream). Oxygen is then transported by red blood cells to tissues throughout the body for cellular respiration. Choice A is incorrect as oxygen moves from the alveoli into the bloodstream, not the other way around. Choice C is incorrect as oxygen is not converted into carbon dioxide during gas exchange. Choice D is incorrect as oxygen is not stored in the alveoli but rather continuously exchanged with carbon dioxide during respiration.

2. Which of the following best describes the process of osmosis?

• A. Movement of molecules against their concentration gradient
• B. Movement of water across a selectively permeable membrane
• C. Movement of water and solutes together
• D. Movement of large molecules through a membrane

Correct answer: B

Rationale: The correct answer is B. Osmosis is the process where water moves across a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration. Choice A is incorrect because osmosis does not involve movement against the concentration gradient. Choice C is incorrect because osmosis primarily involves the movement of water, not water and solutes together. Choice D is incorrect as osmosis specifically refers to the movement of water molecules, not large molecules, through a membrane.

3. What are the two main divisions of the skeletal system?

• A. Upper and lower body bones
• B. Axial and appendicular skeleton
• C. Long and short bones
• D. Compact and spongy bone

Correct answer: B

Rationale: The skeletal system is divided into two main divisions: the axial skeleton and the appendicular skeleton. The axial skeleton comprises the skull, vertebral column, and rib cage, providing structural support and protection for vital organs. On the other hand, the appendicular skeleton includes the bones of the upper and lower limbs, shoulder girdle, and pelvic girdle, facilitating movement and flexibility. The divisions are based on the location and function of the bones within the skeletal system, making choices A, C, and D incorrect as they do not represent the primary divisions of the skeletal system.

4. What is the primary function of B cells in the immune system?

• A. Directly attacking and engulfing pathogens
• B. Producing antibodies specific to a pathogen
• C. Destroying infected body cells
• D. All of the above

Correct answer: B

Rationale: B cells are a type of white blood cell that primarily functions by producing antibodies specific to a pathogen. These antibodies play a crucial role in marking pathogens for destruction by other immune cells. While B cells are essential for the immune response, they do not directly attack and engulf pathogens or destroy infected body cells. These functions are carried out by other immune cells like macrophages and cytotoxic T cells. Therefore, the correct answer is B, as it accurately reflects the primary role of B cells in the immune system.

5. What is the difference between a homozygous recessive genotype and a homozygous dominant genotype?

• A. Both have the same phenotype, but different genotypes.
• B. Both have the same genotype, but different phenotypes.
• C. Homozygous recessive has two dominant alleles, while homozygous dominant has two recessive alleles.
• D. Homozygous recessive has two identical recessive alleles, while homozygous dominant has two identical dominant alleles.

Correct answer: D

Rationale: - Homozygous recessive genotype refers to an individual having two identical recessive alleles for a particular gene (e.g., rr for a trait where r represents the recessive allele). - Homozygous dominant genotype refers to an individual having two identical dominant alleles for a particular gene (e.g., RR for a trait where R represents the dominant allele). - The difference between the two genotypes lies in the specific alleles present in each case, with homozygous recessive having two recessive alleles and homozygous dominant having two dominant alleles. - This genetic difference results in different phenotypes being expressed, as the dominant allele typically masks the expression of the recessive allele in heterozygous individuals.

Similar Questions