1. Which of the following is NOT a major division of the nervous system?

A. Peripheral nervous system
B. Central nervous system
C. Somatic nervous system
D. Autonomic nervous system

Correct answer: C

Rationale: The somatic nervous system is actually a component of the peripheral nervous system, responsible for voluntary control of skeletal muscles and sensory information. The major divisions of the nervous system are the central nervous system (which includes the brain and spinal cord) and the peripheral nervous system (which includes all nerves outside the central nervous system). The autonomic nervous system, on the other hand, is a division of the peripheral nervous system responsible for involuntary functions like heart rate and digestion. Therefore, the correct answer is C, the somatic nervous system, as it is not a major division of the nervous system.

2. What information can be obtained directly from the element's atomic number?

A. Its atomic mass
B. Its position on the periodic table
C. Its position on the periodic table
D. Its chemical properties

Correct answer: B

Rationale: The atomic number of an element represents the number of protons in the nucleus of an atom. This number determines the element's unique identity and its position on the periodic table. The atomic mass (option A) is not directly determined by the atomic number but is a weighted average of the isotopes of an element. The position on the periodic table (option C) is directly related to the atomic number, as elements are arranged in order of increasing atomic number. The chemical properties of an element (option D) are influenced by the number of protons in the nucleus, which is determined by the atomic number.

3. Maintaining good muscle strength and flexibility as we age becomes important to avoid:

A. Headaches
B. Falls
C. Anxiety
D. Common cold

Correct answer: B

Rationale: The correct answer is B: 'Falls.' Maintaining good muscle strength and flexibility as we age is crucial for preventing falls, which become more common with age and can lead to serious injuries such as fractures. Strong muscles and good flexibility help in maintaining balance and stability, reducing the risk of falls. Headaches, anxiety, and the common cold are not directly related to muscle strength and flexibility, making them less likely to be avoided by focusing on these aspects of physical health.

4. Which of the following is an example of aseptic technique?

A. Washing hands with soap and water before surgery
B. Coughing into your elbow
C. Sharing a stethoscope without cleaning
D. Leaving a wound dressing exposed

Correct answer: A

Rationale: Rationale: Aseptic technique refers to practices that help prevent the introduction of harmful microorganisms into a sterile environment. Washing hands with soap and water before surgery is an essential component of aseptic technique as it helps reduce the number of microorganisms on the hands, decreasing the risk of introducing pathogens into the surgical site. Coughing into your elbow is a good hygiene practice to prevent the spread of respiratory infections but is not specifically related to aseptic technique. Sharing a stethoscope without cleaning can introduce microorganisms from one patient to another, compromising aseptic conditions. Leaving a wound dressing exposed can lead to contamination and infection, which is contrary to aseptic technique.

5. A keystone species plays a critical role in an ecosystem because its removal would:

A. Lead to a decrease in competition among other species
B. Cause a slight increase in primary productivity
C. Have a minimal impact on the overall ecosystem structure
D. Disrupt the food web and cause cascading effects on other populations

Correct answer: D

Rationale: Rationale: Keystone species are species that have a disproportionately large effect on their environment relative to their abundance. They play a critical role in maintaining the structure and function of an ecosystem. If a keystone species is removed from an ecosystem, it can disrupt the food web by causing imbalances in predator-prey relationships. This disruption can lead to cascading effects on other populations within the ecosystem, potentially causing population declines or even extinctions. Therefore, the removal of a keystone species would have significant impacts on the overall ecosystem structure, making option D the correct answer.

6. Which statement correctly describes the concept of ionization energy?

A. The energy required to remove an electron from an outermost shell.
B. The energy released when an electron bonds with an atom.
C. The total energy possessed by all electrons in an atom.
D. The energy needed to change an atom's nucleus.

Correct answer: A

Rationale: The energy required to remove an electron from an outermost shell. Ionization energy varies depending on the element and electron configuration, indicating its difficulty to lose electrons and influencing its reactivity.