answer to question 6: Plants absorb energy from the sun and use photosynthesis to make sugars.. Animals have mitochondria that use the sugars provided by plants to produce their own cellular energy.
Answer to 7: Humans don't take their energy from the sun directly, they eat plants and use the sugars and starches in those plants for their chemical energy. Animals also eat plants and then we eat those animals as a source of amino acids that are then used to build and repair our body.
answer to 8:i dont know if this answer will help or not sorry: The relationship between photosynthesis and cellular respiration is such that the products of one system are the reactants of the other. Photosynthesis involves the use of energy from sunlight, water and carbon dioxide to produce glucose and oxygen. Cellular respiration uses glucose and oxygen to produce carbon dioxide and water. To emphasize this point even more, the equation for photosynthesis is the opposite of cellular respiration.
9: they need energy to stay alive and grow
