Groups of five plants are given 1, 2, and 3 grams of nitrate and 1, 2, and 3 grams of phosphate in all combinations over a perio
d of one month. The researcher measures plant height and weight at the end of the experiment. What is missing in this experimental design? Question 9 options:
Melanin is the pigment which absorbs UV light and it is present in skin and gives black colour to it.As we can see africans usually have black skin as they have to face direct uv light.
