In botany, plant cuticles are protective, hydrophobic, waxy coverings produced by the epidermal cells of leaves, young shoots and all other aerial plant organs.Cuticles minimize water loss and effectively reduce pathogen entry due to their waxy secretion.he cuticle both prevents plant surfaces from becoming wet and helps to prevent plants from drying out. Xerophytic plants such as cactus have very thick cuticles to help them survive in their arid climates.
radiometric dating. n. 1. (Archaeology) any method of dating material based on the decay of its constituent radioactive atoms, such as potassium-argon dating or rubidium-strontium dating. Also called: radioactive dating.
Uranium-lead radiometric dating involves using Uranium-235 or Uranium-238 to date a substance's absolute age. This scheme has been refined to the point that the error margin in dates of rocks can be as low as less than two million years in two-and-a-half billion years.