Reproductive structures similar to the egg in other kingdoms are termed "spores", or in spermatophytes "seeds", or in gametophytes "egg cells". Most arthropods, vertebrates (excluding live-bearing mammals), and mollusks lay eggs, although some, such as scorpions, do not.
Eggs provide many vitamins, antioxidants, and protein. But they're also high in cholesterol, so the number of eggs that are okay to have can depend on your health. The yolk in eggs can...
Eggs pack an impressive nutrient punch. Importantly, while both the yolk and white contain protein, the yolk is much higher in other essential nutrients. One large egg (50 grams) has approximately 6.5 grams of protein, 5 grams of fat, 0.5 gram of carbohydrate, and 70 calories.