Correct Answer: B

Rationale: The alveoli are tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide takes place. Oxygen from inhaled air diffuses into the blood vessels surrounding the alveoli, while carbon dioxide from the blood is released into the alveoli to be exhaled. The bronchi are air passages that carry air into the lungs but do not participate in gas exchange. The trachea is the windpipe that connects the larynx to the bronchi and serves as an airway for breathing. The diaphragm is a muscle that aids in the breathing process by contracting and relaxing to change the volume of the chest cavity.

Correct Answer: B

Rationale: In the scientific method, defining the problem is typically the initial step. Before gathering qualitative data, it is essential to clearly outline and understand the issue or question being addressed. This step helps in guiding the research process and ensures that the data collected are relevant to the problem at hand. Communicating with a scientific journal (Choice A) is not a standard step in the scientific method; it comes after the research is conducted. Developing a hypothesis (Choice C) usually follows defining the problem and precedes data collection. Categorizing data for statistical analysis (Choice D) occurs after data collection, not before gathering qualitative data.

Correct Answer: D

Rationale: The cerebrum is the correct answer as it is responsible for higher brain functions like thought and action. The amygdala (Choice A) is involved in emotions and emotional responses, not higher brain functions. The brain stem (Choice B) controls basic life functions such as breathing and heart rate, not higher brain functions. The cerebellum (Choice C) is mainly responsible for motor control and coordination, not higher brain functions like thought and action.

Correct Answer: B

Rationale: The correct answer is B: Ball-and-socket joint. A ball-and-socket joint, like those in the shoulder and hip, allows for a wide range of motion. In a ball-and-socket joint, the rounded end of one bone fits into the cup-like socket of another bone, enabling movement in multiple directions. Choice A, Hinge joint, is incorrect because hinge joints allow movement only in one plane, like a door hinge. Choice C, Pivot joint, is incorrect as it allows rotational movement around a single axis, not the wide range of motion seen in the shoulder and hip. Choice D, Saddle joint, is also incorrect as it allows movement in multiple directions but to a lesser extent compared to the ball-and-socket joint.

Correct Answer: B

Rationale: The correct answer is B, Somatic. The somatic nervous system controls voluntary movements of skeletal muscles. It is responsible for carrying sensory and motor information to and from the central nervous system. Choices A, C, and D are incorrect. The autonomic nervous system (choice A) controls involuntary functions such as heart rate and digestion. The sympathetic (choice C) and parasympathetic (choice D) nervous systems are subdivisions of the autonomic nervous system and are responsible for the body's fight-or-flight response and rest-and-digest functions, respectively.