Nursing Elites

1. What are the tiny contractile units within muscle cells called?

• A. Myocytes
• B. Myofibrils
• C. Sarcomeres
• D. Tendons

Correct answer: C

Rationale: Sarcomeres are the smallest contractile units within muscle cells. They consist of overlapping filaments of actin and myosin proteins, which interact to produce muscle contractions. Myocytes are the entire muscle cells, myofibrils are bundles of protein filaments found within muscle cells, and tendons are tough connective tissues that connect muscles to bones. Therefore, sarcomeres specifically represent the contractile units responsible for muscle contraction, making them the correct answer in this context.

2. Which type of muscle tissue is found in the walls of blood vessels and helps regulate blood flow?

• A. Skeletal muscle
• B. Smooth muscle
• C. Cardiac muscle
• D. Striated muscle

Correct answer: B

Rationale: Smooth muscle is the correct answer. It is found in the walls of blood vessels and helps regulate blood flow by contracting and relaxing to adjust the diameter of the vessels. Skeletal muscle, found attached to bones, is responsible for voluntary movements and is not typically found in blood vessel walls. Cardiac muscle is specific to the heart and responsible for pumping blood, not found in blood vessel walls. Striated muscle, another term for skeletal muscle, is characterized by its striped appearance under a microscope but is not present in blood vessel walls.

3. What is the science of classifying organisms into different groups based on their evolutionary relationships called?

• A. Taxonomy
• B. Microbiology
• C. Genetics
• D. Epidemiology

Correct answer: A

Rationale: Taxonomy is the science of classifying organisms into different groups based on their evolutionary relationships. It involves identifying, naming, and categorizing living organisms according to their similarities and differences, helping us understand the diversity of life. Microbiology (option B) focuses on the study of microorganisms. Genetics (option C) deals with genes and heredity. Epidemiology (option D) explores the distribution and determinants of health-related states or events in populations. Therefore, the correct answer is Taxonomy as it specifically pertains to the classification of organisms based on their evolutionary relationships.

4. Which division of the peripheral nervous system is responsible for transmitting signals from the central nervous system to skeletal muscles, enabling voluntary muscle movements?

• A. Somatic nervous system
• B. Autonomic nervous system
• C. Sympathetic nervous system
• D. Parasympathetic nervous system

Correct answer: A

Rationale: The correct answer is the somatic nervous system. The somatic nervous system is responsible for transmitting signals from the central nervous system to skeletal muscles, allowing for voluntary muscle movements. The autonomic nervous system, sympathetic nervous system, and parasympathetic nervous system are not involved in voluntary muscle movements. Instead, they regulate involuntary functions of the body such as heart rate, digestion, and breathing. Therefore, choices B, C, and D are incorrect as they are not associated with voluntary muscle movements.

5. Which of the following is NOT a greenhouse gas?

• A. Carbon dioxide
• B. Water vapor
• C. Nitrogen
• D. Methane

Correct answer: C

Rationale: Rationale: A) Carbon dioxide: Carbon dioxide is a greenhouse gas that is naturally present in the Earth's atmosphere and is also released through human activities such as burning fossil fuels. B) Water vapor: Water vapor is a greenhouse gas that is naturally present in the atmosphere and plays a significant role in the Earth's climate system. C) Nitrogen: Nitrogen is not considered a greenhouse gas because it does not have the ability to absorb and emit infrared radiation in the same way that greenhouse gases like carbon dioxide and methane do. D) Methane: Methane is a potent greenhouse gas that is released through natural processes such as wetland decomposition and human activities such as livestock farming and fossil fuel extraction. Therefore, the correct answer is C) Nitrogen, as it is not a greenhouse gas.

Similar Questions