What is the function of the stratified cuboidal epithelium lining the salivary glands?

Correct Answer: C

Rationale: The correct answer is C: Secretion. The stratified cuboidal epithelium lining the salivary glands is responsible for secretion. This type of epithelium, made of multiple layers of cube-shaped cells, is specialized for secretion and protection. In the salivary glands, these cells secrete saliva to aid in the digestion process. Choice A, Protection, is incorrect because while the epithelium does provide some level of protection, its primary function in the salivary glands is secretion. Choice B, Gas exchange, is incorrect as the salivary glands are not involved in gas exchange processes. Choice D, Absorption, is also incorrect as the main role of this epithelium in the salivary glands is not absorption but rather secretion of saliva.

Correct Answer: A

Rationale: The table is much heavier than the book, so it requires a much larger force to accelerate it. The book is lighter and easier to move, so the force applied to it causes it to move without significantly affecting the table due to the table's greater mass. Newton's third law states that for every action, there is an equal and opposite reaction. In this case, the force exerted on the book by the table is countered by an equal force exerted on the table by the book, but the table's greater mass resists movement. Choice B is incorrect because the forces are equal and opposite, acting in the same direction. Choice C is incorrect as the surface area does not affect the movement of the table in this scenario. Therefore, the correct answer is A, as the table's greater mass prevents it from moving easily when a force is applied.

Correct Answer: C

Rationale: Refraction occurs due to a change in wave speed when waves enter a new medium. As waves travel from one medium to another, their speed changes, causing them to bend. This change in speed is responsible for the bending of waves during refraction. It is not the change in wavelength or frequency that causes refraction, but rather the change in speed as waves move through different mediums. Therefore, the correct answer is the change in wave speed (Choice C). Choices A and B are incorrect as refraction is not primarily influenced by changes in wavelength or frequency, but by changes in wave speed. Choice D is also incorrect as there is a specific principle, which is the change in wave speed, behind the phenomenon of refraction.

Correct Answer: B

Rationale: Heat and temperature are distinct concepts. Heat is a form of energy that transfers from a higher temperature object to a lower temperature object, while temperature represents the average kinetic energy of particles in a substance. Heat is quantified in units like Joules or calories, whereas temperature is typically gauged in degrees Celsius or Fahrenheit. Therefore, choice B correctly distinguishes between heat and temperature, making it the correct answer. Choices A, C, and D are incorrect because they do not accurately define the difference between heat and temperature. Choice A erroneously suggests they are the same, choice C confuses the direction of heat and temperature flow, and choice D provides inaccurate units for measuring heat and temperature.

Correct Answer: A

Rationale: The correct answer is A. Real images can be projected onto a screen because they are formed by the actual convergence of light rays, while virtual images cannot be projected onto a screen as they appear to diverge from a point behind the lens. Real and virtual images do not have a consistent orientation (upright or inverted), so option B is incorrect. Real images are formed by both converging and diverging lenses depending on the specific scenario, so option C is not a definitive distinction. Option D is incorrect as not all the statements are true. Therefore, the only accurate general distinction between real and virtual images is that real images can be projected onto a screen, while virtual images cannot.