Instead, it stated that the decision to get routine screening mammograms before age 50 should be an individual one and take patient context into account, including the patient's values regarding specific benefits and harms..
The seed coat helps protect the embryo from mechanical injury, predators and drying out. Depending on its development, the seed coat is either bitegmic or unitegmic. Bitegmic seeds form a testa from the outer integument and a tegmen from the inner integument while unitegmic seeds have only one integument.
This is a problem for the germination of the seed because the growing embryo needs oxygen and water. Some seeds will not be able to germinate until the seed coat has been damaged so that water can enter and the embryo can respire. The seed coat may be damaged when the seed is in the soil.