Photosynthesis uses the sun's energy. Which of the following steps would use that energy?
releasing oxygen
combining carbon dioxide and hydrogen
absorbing carbon dioxide
splitting water into hydrogen and oxygen
The step that would use the sun's energy in photosynthesis is the splitting of water into hydrogen and oxygen. This process, known as photolysis, occurs during the light-dependent reactions of photosynthesis and requires light energy to break the water molecules apart into their constituent elements. The resulting oxygen is then released as a waste product, while the hydrogen is combined with carbon dioxide to produce glucose during the light-independent reactions of photosynthesis.
The step that uses the sun's energy in photosynthesis is splitting water into hydrogen and oxygen.
Photosynthesis is the process by which plants, algae, and some bacteria convert sunlight into chemical energy in the form of glucose. The sun's energy is used in two main steps of photosynthesis:
1. Splitting water into hydrogen and oxygen: The energy from sunlight is absorbed by specialized pigments called chlorophylls, located in the chloroplasts of plant cells. This energy is used to split water molecules into hydrogen ions (H+) and oxygen gas (O2) through a process known as photolysis.
2. Combining carbon dioxide and hydrogen: The high-energy electrons generated by sunlight are transferred to a molecule called nicotinamide adenine dinucleotide phosphate (NADP+), converting it into NADPH. These electrons, along with NADPH and ATP (energy molecules produced in an earlier step), are then used to convert carbon dioxide (CO2) into glucose, a process known as the Calvin cycle or the dark reaction of photosynthesis.
So, the correct answer is: splitting water into hydrogen and oxygen.