Correct Answer: D

Rationale: Frequency is the property of a wave that is measured in Hertz (Hz). It represents the number of complete cycles of the wave that occur in one second. Amplitude refers to the height of the wave, wavelength is the distance between two consecutive points on a wave that are in phase, and speed is the rate at which the wave travels through a medium. Therefore, the correct answer is frequency as it directly corresponds to the unit Hertz (Hz) used to measure the number of wave cycles per second.

Correct Answer: B

Rationale: The pituitary gland is commonly referred to as the master gland because it controls the functions of numerous other endocrine glands in the body. It secretes various hormones that are essential for regulating processes like growth, metabolism, reproduction, and stress response. The thyroid gland (Choice A) primarily regulates metabolism and does not oversee other endocrine glands. The hypothalamus (Choice C) plays a role in regulating the pituitary gland but is not the master gland. The adrenal gland (Choice D) produces hormones related to stress response but is not considered the master gland that regulates other endocrine glands.

Correct Answer: B

Rationale: The recommended daily intake of protein for adults to maintain healthy muscle mass is typically around 1 gram per kilogram of body weight. This amount can vary based on individual factors such as activity level, age, and overall health status. Consuming an adequate amount of protein is essential for muscle repair and growth, as well as overall health and functioning of the body. Choices A, C, and D are incorrect because they suggest protein intake levels that are either too low (A) or unnecessarily high (C and D) for maintaining healthy muscle mass. Excessive protein intake can strain the kidneys and may not provide additional benefits for muscle health beyond the recommended levels.

Correct Answer: C

Rationale: The hypothalamus is responsible for regulating body temperature, hunger, and thirst, making it a vital component in maintaining homeostasis. It also plays a crucial role in the endocrine system by controlling the release of hormones from the pituitary gland. The amygdala primarily processes emotions, the hippocampus is associated with memory formation, and the thalamus acts as a relay station for sensory information. Therefore, the hypothalamus is the correct answer as it directly regulates the physiological processes mentioned in the question.

Correct Answer: B

Rationale: The correct answer is B: Base. A base is a substance that can donate hydroxide ions (OH-) in solution. Bases increase the concentration of hydroxide ions by either accepting protons (H+) or donating hydroxide ions. Salts are ionic compounds made of cations and anions, which do not directly donate hydroxide ions. Neutral compounds do not significantly affect the concentration of hydroxide ions. Dehydrating agents are substances that remove water molecules from other compounds, unrelated to donating hydroxide ions.