Nursing Elites

1. Electrons occupy specific energy levels around the nucleus, but not in fixed orbits. This concept is captured by the:

• A. Bohr model
• B. Quantum mechanical model
• C. Lewis structure
• D. Octet rule

Correct answer: B

Rationale: Quantum mechanical model. Unlike the Bohr model with its defined electron paths, the quantum mechanical model uses probability distributions to describe electron locations within energy levels.

2. Passive transport does not require energy input from the cell. Which of the following is an example of passive transport?

• A. Active transport of ions across a membrane
• B. Diffusion of small molecules across a concentration gradient
• C. Movement of large molecules using vesicles
• D. Endocytosis of particles into the cell

Correct answer: D

Rationale: Passive transport refers to the movement of molecules across a cell membrane without the need for energy input. Endocytosis is an example of passive transport because it involves the cell engulfing particles or molecules from the external environment into vesicles without the direct expenditure of energy. On the other hand, options A, B, and C involve active processes that require energy. Active transport, such as the movement of ions against their concentration gradient, requires energy in the form of ATP. Diffusion of small molecules across a concentration gradient also does not require energy input, but it is a passive process, not active transport. Movement of large molecules using vesicles is a form of active transport called vesicular transport. Therefore, the correct answer is D, endocytosis of particles into the cell, as it exemplifies passive transport without the need for energy consumption by the cell.

3. Where does cellular respiration, the process of converting chemical energy into ATP, take place in eukaryotic cells?

• A. Nucleus
• B. Ribosomes
• C. Mitochondria
• D. Golgi apparatus

Correct answer: C

Rationale: Rationale: Cellular respiration, the process of converting chemical energy into ATP, takes place in the mitochondria of eukaryotic cells. The mitochondria are known as the powerhouse of the cell because they are responsible for generating most of the cell's ATP through the process of cellular respiration. This process involves the breakdown of glucose and other organic molecules to produce ATP, which is the primary energy currency of the cell. The other organelles listed in the options (nucleus, ribosomes, and Golgi apparatus) do not play a direct role in cellular respiration.

4. What happens to the gravitational potential energy of an object as it falls freely?

• A. It decreases
• B. It increases
• C. It remains constant
• D. It becomes zero

Correct answer: a

Rationale: Gravitational potential energy decreases as an object falls freely due to a decrease in its height.

5. What is the significance of cell division?

• A. Growth and repair of tissues
• B. Sexual reproduction
• C. Genetic diversity
• D. All of the above

Correct answer: D

Rationale: Cell division is a fundamental process that is essential for the growth, repair, and reproduction of all living organisms. It plays a crucial role in ensuring that organisms maintain their proper size and shape, and it allows for the replacement of damaged or worn-out cells. Cell division is also essential for sexual reproduction, as it is the process by which haploid gametes (sex cells) are produced. These gametes fuse during fertilization to form a diploid zygote, which ultimately gives rise to a new organism.

6. The term "double circulation" in the cardiovascular system refers to

• A. The separation of oxygenated and deoxygenated blood flow within the heart.
• B. The regulation of blood pressure through vasoconstriction and vasodilation
• C. The cyclic contraction and relaxation of the heart muscle.
• D. The existence of two separate circulatory pathways, one for the lungs and one for the body.

Correct answer: D

Rationale: The term 'double circulation' in the cardiovascular system refers to the existence of two separate circulatory pathways, one for the lungs (pulmonary circulation) and one for the body (systemic circulation). In pulmonary circulation, deoxygenated blood is pumped from the heart to the lungs to pick up oxygen and release carbon dioxide. Then, oxygenated blood returns to the heart to be pumped out to the rest of the body in systemic circulation. This separation of oxygenated and deoxygenated blood flow in different pathways is what distinguishes the double circulation system. Therefore, option D is the correct answer as it accurately describes the concept of double circulation in the cardiovascular system.

Similar Questions