There are many different cell types and sub-types involved in the immune system. Some of the main types include: Lymphocytes: are white cells which circulate between blood and lymph. They play an important role in fighting infection.
After about 50 to 60 days, beets are ready to harvest. Not only can the roots be dug up and chopped to add flavor to a meal, but the greens of the beets can be harvested periodically and put in salads. Given how well these beets fare in different weather conditions, they can be grown several times in a summer.
Place in a saucepan covered with salted water to taste (with at least 1 tsp of vinegar). Boil until tender [usually, 30-45 minutes, depending on the size of the beets]. Boiling can take up to 60 minutes for larger beets. Drain and run cold water over beets. The skins will slip right off with the root ends, but make sure you wear kitchen gloves so your hands don't turn red.