Question

Which of the following is correct about biosynthetic phase? (a) \(\mathrm{C}_{14}\) isotope is used to find out this pathway (b) Calvin worked on this pathway (c) Melvin Calvin used photosynthetic algae for this pathway (d) All the above

Short answer

The correct answer is (d) All the above.

Step-by-step solution

Understand the options

Option (a) claims that the \(\mathrm{C}_{14}\) isotope is used to trace this pathway. Option (b) states Calvin worked on this pathway. Option (c) suggests Melvin Calvin employed photosynthetic algae for researching this pathway. Option (d) posits all the previous options are correct.

Evaluate Option (a)

Melvin Calvin indeed used \(\mathrm{C}_{14}\), a radioactive isotope of Carbon, to trace the path of carbon in the photosynthesis process, particularly in the biosynthetic phase (Calvin cycle). So, option (a) is correct.

Evaluate Option (b)

The biosynthetic phase, which is also known as the Calvin Cycle, is indeed named this way because Melvin Calvin was the main researcher in its discovery and analysis. So, option (b) is also correct.

Evaluate Option (c)

Melvin Calvin did use photosynthetic algae, specifically Chlorella, for his work on the biosynthetic phase of photosynthesis. So, option (c) is also correct.

Check if all the options are correct

Since all the individual options (a), (b), and (c) are correct, the resulting answer would indeed be option (d) - all of the above.

Key concepts

Biosynthetic Phase

The biosynthetic phase, often referred to as the Calvin Cycle, is a crucial part of the photosynthesis process in plants. It represents the stage where carbon fixation happens—transforming carbon dioxide from the air into organic molecules like glucose.
The Calvin Cycle occurs in the chloroplasts and is guided by enzymes to gradually build carbon into complex carbohydrates. This metabolic pathway doesn't directly rely on light but instead uses products of the light-dependent reactions, such as ATP and NADPH, to fuel its processes.
Think of it like a biological factory where plants synthesize food, powering the plant’s growth and development. Understanding this phase is key to comprehending how plants convert inorganic carbon into life-sustaining organic compounds.

Photosynthesis

Photosynthesis is the amazing process where plants, algae, and some bacteria convert light energy into chemical energy stored in glucose. This process is vital for life on Earth as it provides the oxygen we breathe and the food energy that sustains nearly every living organism.
During photosynthesis, chlorophyll within the chloroplasts captures sunlight, which ignites a series of chemical reactions. These reactions occur in two stages: the light-dependent reactions and the light-independent reactions (commonly known as the Calvin Cycle or biosynthetic phase).

• Light-dependent reactions: Take place in the thylakoid membranes, where sunlight is captured and converted into chemical energy, resulting in ATP and NADPH.
• Light-independent reactions: Also known as the Calvin Cycle, where the plant uses ATP and NADPH to fix carbon dioxide into glucose.

Photosynthesis not only supports plant life but also forms the base of the abundance of life on our planet by initiating most food chains.

Melvin Calvin

Melvin Calvin was a pioneering scientist who significantly contributed to our understanding of the photosynthesis process, primarily focusing on the Calvin Cycle. His groundbreaking work in the mid-20th century unveiled the path of carbon in photosynthesis, which became instrumental for further research in plant biology.
One of Calvin’s notable achievements was using radioactively labeled carbon, specifically \(^{14} ext{C}\), to trace the pathways of carbon as it turns into sugars during photosynthesis. Experimenting with photosynthetic algae like Chlorella, he unravelled how carbon dioxide is assimilated into organic compounds.
In recognition of his contributions, the cycle he studied and clarified was named the Calvin Cycle in his honor. Melvin Calvin's work is a cornerstone of plant biochemistry, contributing a profound understanding that informs everything from agriculture to biofuels.