A person with lactose intolerance should be most careful to limit their intake of:

Correct Answer: A

Rationale: Individuals with lactose intolerance lack the enzyme lactase needed to break down lactose, the sugar in dairy products. Milk contains a high amount of lactose, making it crucial for those with lactose intolerance to limit their intake. Yogurt and cheese, on the other hand, have lower lactose content due to the fermentation process which reduces lactose levels, making them better tolerated by many with lactose intolerance. Corn syrup, although high in sugar, does not contain lactose and is unrelated to lactose intolerance. Therefore, the correct answer is 'milk' as it is a significant source of lactose, which can trigger symptoms in individuals with lactose intolerance.

Correct Answer: D

Rationale: Fructose is known to be the sweetest among naturally occurring sugars. While glucose, sucrose, and galactose also have sweet tastes, fructose is commonly perceived as the sweetest due to its higher level of sweetness. Glucose is a simple sugar found in many carbohydrates; sucrose is table sugar composed of glucose and fructose; galactose is a component of lactose found in dairy products. However, when comparing the sweetness levels of these sugars, fructose stands out as the sweetest.

Correct Answer: C

Rationale: The correct answer is C: Chlorophyll. Chlorophyll is a pigment that is essential for photosynthesis as it absorbs light energy, allowing plants to convert carbon dioxide and water into glucose, a process crucial for plant growth. Glucose (choice A) is produced during photosynthesis and is not an ingredient necessary for the process itself. Nitrogen (choice B) is important for plant growth but is not a direct ingredient for photosynthesis. Hydrogen (choice D) is found in water, which is indeed one of the necessary ingredients for photosynthesis, but chlorophyll is specifically required to capture light energy for the process to occur.

Correct Answer: A

Rationale: Carbohydrates are composed of carbon, hydrogen, and oxygen. These three elements combine to form the basic structure of carbohydrates. Oxygen is an essential element in carbohydrates, contributing to their chemical composition. Choice B (nitrogen) is incorrect as nitrogen is not a typical component of carbohydrates. Choice C (water) is incorrect as water is not an element but a compound composed of hydrogen and oxygen. Choice D (glucose) is incorrect as glucose is a specific type of sugar, not an element found in the composition of carbohydrates.

Correct Answer: A

Rationale: The correct answer is A: carbohydrates. Photosynthesis is the process by which plants, algae, and some bacteria convert light energy, usually from the sun, into chemical energy stored in glucose (a type of carbohydrate). This glucose is used by the organisms for energy production and as a building block for other organic compounds. Choice B, proteins, is incorrect because proteins are synthesized through a different process involving amino acids. Choice C, fats, are not directly synthesized through photosynthesis; they are typically formed from excess carbohydrates. Choice D, vitamins, are organic compounds that are required in small amounts for various physiological functions but are not directly synthesized through photosynthesis.