Correct Answer: B

Rationale: The correct answer is False. The digestive system is responsible for breaking down food and absorbing nutrients, not filtering wastes from the blood. The excretory system, particularly the kidneys, filters wastes from the blood to form urine. Choices A, C, and D are incorrect because the digestive system's primary function is not waste filtration but rather digestion and absorption of nutrients.

Correct Answer: C

Rationale: Wrinkled and sagging skin is primarily caused by the loss of subcutaneous fat and reduced levels of elastin and collagen in the skin. Choice A is incorrect as drinking too much water does not lead to wrinkled and sagging skin. Choice B is incorrect because heredity alone does not cause this condition. Excess subcutaneous fat, as mentioned in Choice D, can contribute to a different skin appearance, such as puffiness, but not wrinkled and sagging skin.

Correct Answer: A

Rationale: The statement is true. The field of medicine evolved as early healers moved away from superstition and magic, instead focusing on natural chemicals to treat illnesses. This transition marked a shift towards a more scientific and evidence-based approach to healthcare. Choice B is incorrect because the statement accurately reflects the historical development of medicine. Choice C is incorrect as the historical transition from superstition to natural chemicals is a well-documented aspect of the evolution of medicine. Choice D is incorrect as the statement provided is true.

Correct Answer: A

Rationale: The correct answer is A: Monomers. Macromolecules are built from smaller subunits called monomers. Monomers join together through chemical reactions to form larger molecules known as macromolecules. Option B is incorrect because it does not provide the accurate information regarding macromolecules. Option C is incorrect as it indicates uncertainty, which is not the case here. Option D is incorrect as there is a specific answer related to the composition of macromolecules.

Correct Answer: B

Rationale: Organelles are not exclusive to human cells but are present in various types of cells across different organisms. Option B is incorrect as it suggests that organelles are only found in human cells, which is false. Choices A, C, and D are correct statements about organelles. Organelles indeed carry out specific activities, are made up of aggregates of large molecules, and can be found in many types of cells.