Question

based on what you have learned about photosynthesis, select the true statements.
food provides an organism with energy - rich molecules, which are broken down in cells.
the chemical bonds between atoms change during photosynthesis.
the reactants of photosynthesis are made of different types of atoms than the products.
photosynthesis uses light energy to produce food molecules.

Explanation:

• Food provides energy - rich molecules (like glucose) that are broken down in cells (through cellular respiration) to release energy.
• Photosynthesis is a chemical reaction. In a chemical reaction, the chemical bonds between atoms change. For example, in photosynthesis, bonds in \(CO_2\) and \(H_2O\) are broken and new bonds are formed in glucose (\(C_6H_{12}O_6\)) and \(O_2\).
• According to the law of conservation of mass, the types of atoms remain the same in a chemical reaction. The reactants (\(CO_2\) and \(H_2O\)) and products (\(C_6H_{12}O_6\) and \(O_2\)) of photosynthesis are made of the same types of atoms (\(C\), \(H\), and \(O\)). So, this statement is false.
• The overall equation of photosynthesis is \(6CO_2 + 6H_2O+light\ energy

ightarrow C_6H_{12}O_6 + 6O_2\). It uses light energy (captured by chlorophyll) to produce food (glucose) molecules.

Answer:

• Food provides an organism with energy - rich molecules, which are broken down in cells.
• The chemical bonds between atoms change during photosynthesis.
• Photosynthesis uses light energy to produce food molecules.