Explain why lipids are well suited as a long-term energy store in animals, compared to carbohydrates.

Lipids contain more energy per gram than carbohydrates, so a smaller amount of lipid stores the same energy.
Lipids are insoluble in water; this means they do not interfere with the water potential or osmotic balance of cells.
Because they are insoluble, lipids can be stored in adipose tissue without affecting cell volume or water balance.
Adipose tissue also provides insulation and protection for the body.
In contrast, glycogen is soluble and is used for short‑term, immediate energy needs rather than long‑term storage.