Final answer:
Single-celled algae utilize photosynthesis to convert sunlight into chemical energy and cellular respiration to convert that chemical energy into a usable form, cycling matter and flowing energy within the cell.
Step-by-step explanation:
Using the relationship between photosynthesis and respiration, we can explain how matter is cycled and energy flows within a single-celled algae.
Photosynthesis is the process by which algae and other photosynthetic organisms use sunlight to convert carbon dioxide and water into glucose and oxygen. This is not only a crucial process for the synthesis of food but also for the cycling of matter, as carbon is fixed into a more stable form (glucose).
Cellular respiration, on the other hand, is the process wherein glucose is broken down with the use of oxygen to produce carbon dioxide, water, and energy in the form of ATP (adenosine triphosphate). This metabolic process leads to the release of energy that the cell can use to perform various functions.
Together, photosynthesis and cellular respiration constitute a biogeochemical cycle where the output of one serves as the input for the other, thereby forming the carbon cycle. The energy from the sun is transformed into chemical energy stored in glucose via photosynthesis, and then this chemical energy is converted back into a usable form (ATP) through respiration.
Single-celled algae, like all plants, contain both chloroplasts and mitochondria, which are organelles responsible for photosynthesis and cellular respiration, respectively. The presence of these two organelles allows the algae to perform both processes, thereby enabling them to function in both the presence and absence of light and to continuously cycle matter and transform energy within their cells.
In conclusion, the processes of photosynthesis and cellular respiration in single-celled algae form a continuous loop that facilitates the cycling of matter and the flow of energy throughout the cell, illustrating the profound interconnectedness of these biochemical pathways in supporting life.