| Group 1 | Group 2 | ||
| (P) | Net primary productivity | (i) | Total amount of produced by autotrophs energy |
| (Q) | Gross primary productivity | (ii) | A type of mutualism where one species is benefitted more than the other |
| (R) | Net productivity | (iii) | Amount of energy stored by autotrophs after respiration |
| (S) | Secondary productivity | (iv) | Unused amount of energy after consumption by heterotrophs |