Organ system is the answer according to me if it is one word question
Answer:
C. Nucleus
Explanation:
In both animal and plant cells the nucleus controls all activities in the cell.
Trypins breaks down the protien into simple amino acids which are absorbed by the gut wall.
B. xylem and phloem. they transport water and nutrients throughout the plant
Answer:
food chain- description 3
energy losses- description 5
pyramid of biomass- description 1
pyramid of numbers- description 4
energy flow- description 2
