key term - 700 nm

Definition

700 nm refers to a specific wavelength of light in the electromagnetic spectrum, which falls within the red region. This wavelength is significant in the context of photosynthesis, particularly during the light-dependent reactions where light energy is captured by pigments in photosystems to drive electron transport and ultimately generate energy for the plant.

5 Must Know Facts For Your Next Test

1. 700 nm is close to the upper limit of visible light and corresponds to the color red, which plays a vital role in photosynthesis as plants absorb this wavelength.
2. Light at 700 nm is not as efficiently absorbed by chlorophyll as shorter wavelengths like 430-680 nm, but it still contributes to energy capture.
3. In photosystems, especially Photosystem I, the absorption of light at this wavelength promotes the transfer of electrons, aiding in the synthesis of ATP and NADPH.
4. The use of light at 700 nm reflects a broader strategy by plants to utilize different wavelengths across the visible spectrum for maximum energy absorption.
5. Understanding the role of 700 nm in photosynthesis helps explain how plants adapt to varying light conditions in their environments.

Review Questions

• How does the absorption of light at 700 nm impact the efficiency of photosynthesis?
  • The absorption of light at 700 nm contributes to photosynthesis by enabling plants to capture energy, although it is less efficient than shorter wavelengths. Chlorophyll primarily absorbs blue and red light but still utilizes some energy from longer wavelengths like 700 nm. This absorption allows for a broader spectrum of light utilization, helping plants adapt to different environmental conditions and maximizing their energy capture during photosynthesis.
• Discuss the role of chlorophyll in capturing light at 700 nm during the light-dependent reactions.
  • Chlorophyll plays a crucial role in capturing light energy during the light-dependent reactions of photosynthesis. While it absorbs most efficiently at wavelengths shorter than 700 nm, it can still absorb some light at this wavelength. When chlorophyll captures photons at 700 nm, especially in Photosystem I, it excites electrons that are then transferred through an electron transport chain, leading to ATP and NADPH production necessary for subsequent stages of photosynthesis.
• Evaluate how different wavelengths of light, including 700 nm, influence plant adaptation strategies for photosynthesis.
  • Different wavelengths of light play a significant role in shaping plant adaptation strategies for photosynthesis. Plants have evolved pigments like chlorophyll to absorb a range of wavelengths efficiently, maximizing energy capture from sunlight. The ability to utilize light at 700 nm allows plants to thrive in various environments by adapting their photosynthetic mechanisms to access available light. This flexibility ensures that they can continue to produce energy even when certain wavelengths are less available due to shading or environmental factors.

Related terms

Chlorophyll: The green pigment found in plants that absorbs light energy, primarily in the blue and red wavelengths, to facilitate photosynthesis.

Photosystem: A complex of proteins and pigments in chloroplasts that captures light energy and initiates the process of photosynthesis through electron transport.

Electron Transport Chain: A series of protein complexes and other molecules that transfer electrons from donors to acceptors through redox reactions, ultimately leading to the production of ATP and NADPH in photosynthesis.