There are many essential nutrients to humans. These include calcium, copper, chromium, choline, vitamin A, vitamin B12, as well as protein.
The forgotten nutrient and the most important is water.
Calcium
carrots
Water probably
Vitamin k
yes
yes
An important nutrient would be beta carotene, which the body uses to make Vitamin A.
A nutrient medium is used.
Carbon, Nitrogen, Oxygen
which nutrient supplies the body with the most calories
Nitrogen is the most important Nutrient for turfgrass clorophyll production. Second to that is water (not a nutrient, but a vital part of the nutrient delivery system). Check with you local cooperative extension agency for Nitrogen recommendations in your area, then buy the highest quality, slow release fertilizer you can get and be prepared to water when necessary.