<span>Two major structural differences between cells from kingdoms plantae and animalia; PLANT CELL wall, primarily composed of cellulose, is what provides the whole plant structure support and rigidity.
Animal cells do not have a cell wall, which typically distinguishes them from other The primary function of plant cells is to carry out photosynthesis because of the presence of chlorophyll in their chlorophyll.
Animal cells are unable to synthesize their own food, hence are always dependent on plants.</span>
<span>An example of concentric contraction is doing a biceps curl. The curl exercise is targeting the biceps muscles on the front of the upper arm and only several muscles assist during the movement. Moreover, concentric muscle contraction is a type of muscle activation that increases the tension on a muscle as it shortens and this activation begins the process of muscle strengthening and hypertrophy. </span>
I would say C, his nutrition. Maybe eating more vegetables and fruits will provide him the energy to push harder.
