Question

1. which of these is not a building block of fat (lipid) molecules?

○ sugars
○ glycerol
○ fatty acid

1. why do adult seals need to store a lot of fat molecules as blubber?

○ seals digest the blubber when they hibernate.
○ blubber keeps them warm.
○ blubber helps seals float in the water.
○ blubber makes seals look cute

1. which of these food molecules would your body use for energy first?

Explanation:

Question 3:

Fat (lipid) molecules are built from glycerol and fatty acids. Sugars are carbohydrates, not part of lipid structure.

Adult seals store blubber (fat) to insulate (keep warm) in cold water, aid buoyancy (floating), and for energy during hibernation/fasting. The option "Seals digest the blubber when they hibernate" is incorrect because blubber is stored for use, not digested while hibernating (they use stored energy). Wait, re - evaluating: The question is "Why do adult seals need to store a lot of fat molecules as blubber?". The correct reason related to blubber's function is insulation (keeping warm), aiding floatation, or energy storage. Among the options, "Blubber keeps them warm" is a key function of blubber (insulation). The option "Seals digest the blubber when they hibernate" is a process, not the reason for storing. But if we assume the options are about why store: "Blubber keeps them warm" is correct. Wait, the original question: "Why do adult seals need to store a lot of fat molecules as blubber?". The options:

• Seals digest the blubber when they hibernate (this is what they do with stored blubber, not why store)
• Blubber keeps them warm (reason: insulation)
• Blubber helps seals float in the water (reason: buoyancy, fat is less dense)
• Blubber makes seals look cute (not a biological reason)

So the correct answer related to a valid biological reason for storing blubber is "Blubber keeps them warm" (or "Blubber helps seals float in the water" as fat is less dense, but insulation is a primary reason). If we have to choose the most appropriate from the options as the reason for storing, "Blubber keeps them warm" is a main reason (thermoregulation in cold marine environments).

The body uses carbohydrates (sugars, starches) for energy first, then fats, then proteins. So among food molecules, the body would use carbohydrate - based molecules (like sugars) first for energy. If the options are, for example, sugars, fats, proteins, the answer is sugars. But since the original question's options are not fully visible, assuming typical options: the body's priority for energy is carbohydrates (sugars) first, then fats, then proteins. So the food molecule the body uses for energy first is a carbohydrate (e.g., sugars).

Answer:

A. sugars

Question 4: