Curium is a hard, brittle, radioactive silvery metal. It does not occur in nature and must be made in a nuclear reactor by neutron capture reactions from plutonium and americium isotopes. It tarnishes slowly in dry air at room temperature.
Romaine lettuce is a rich source of fiber and has very few calories, only 8 in a one-cup serving. In terms of vitamins, a cup of Romaine lettuce delivers more than 50% of your daily requirement for vitamin A, as well as significant levels of vitamin K and vitamin C.
Romaine lettuce is super rich in beta-carotene, with approximately 4,094 international unit (IU) of vitamin A in one cup, says the USDA. One cup of iceberg lettuce, however, only contains 361 IU of vitamin A. Vitamin A, a fat-soluble vitamin, is important for your vision, immune system, and reproductive system.inner: Romaine. Vitamin K. Romaine lettuce provides 48 micrograms of vitamin K in a one-cup serving while iceberg lettuce only provides 17 mcg, says ODS. Vitamin K helps your blood to clot appropriately and regulate insulin.