After a baby is born and the umbilical cord is cut, some blood remains in the blood vessels of the placenta and the portion of the umbilical cord that remains attached to it. After birth, the baby no longer needs this extra blood. This blood is called placental blood or umbilical cord blood: 'cord blood' for short.
The easiest way to tell indica vs sativa is to look at the leaves. A true sativa is a tall, scraggly looking plant with wiry stocks and thin leaves. In contrast, indica plants are short and bushy. Indica leaves are usually broad and full. Sativas are native to the warm climates of Mexico, Central America, and Southeast Asia.
Like pure indica, pure sativa strains are high in THC content, which can cause hallucinogenic responses. Generally speaking, indicas are recommended for night-time use, while sativas are a better choice if you need to function during the day, but still take the edge off pain. Of course, most of the medical marijuana people get from dispensaries is neither pure indica nor pure sativa, but a hybrid of both. Some lean more toward the indica part of the scale, others toward the sativa, while still others are nearly 50%-50% hybrids.