Consider the following statements regarding phytoplankton diversity: ...
**Answer:**
The correct answer is option 'A' i.e. statement 1 only.
**Explanation:**
Phytoplankton are microscopic photosynthetic organisms that float in the upper layers of the ocean and other bodies of water. They play a vital role in the marine ecosystem as they form the base of the food chain, produce oxygen through photosynthesis, and help regulate the Earth's climate.
Let's analyze each statement:
**Statement 1: The photosynthetic rate of phytoplankton varies with temperature and light intensity.**
This statement is correct. Photosynthesis is the process by which phytoplankton convert sunlight, carbon dioxide, and nutrients into organic matter and release oxygen as a byproduct. The rate of photosynthesis is influenced by environmental factors such as light intensity and temperature.
Phytoplankton require light for photosynthesis, but excessive light intensity can be harmful to them. Different species of phytoplankton have different optimum light intensity levels at which they can photosynthesize most efficiently. Temperature also affects the rate of photosynthesis, as it influences the metabolic processes of phytoplankton. Higher temperatures usually result in increased photosynthetic rates, up to a certain point, beyond which the rate may decline.
**Statement 2: Phytoplankton cannot grow in areas of low nitrogen concentration.**
This statement is incorrect. While nitrogen is an essential nutrient for phytoplankton growth, they can adapt to varying nitrogen concentrations. Phytoplankton have different strategies to acquire nitrogen, such as utilizing dissolved inorganic nitrogen like nitrate, nitrite, and ammonium, as well as organic nitrogen compounds. They can also take up atmospheric nitrogen through a process called nitrogen fixation.
Some phytoplankton species are better adapted to low nitrogen environments and can outcompete others in such conditions. Additionally, nitrogen availability can vary depending on water column mixing, upwelling, and other factors. Therefore, phytoplankton can still grow and survive in areas with low nitrogen concentration, although their growth rate may be limited compared to areas with higher nitrogen availability.
In conclusion, only statement 1 is correct, while statement 2 is incorrect. The correct answer is option 'A' i.e. 1 only.
Consider the following statements regarding phytoplankton diversity: ...
The photosynthetic rate of phytoplankton varies with temperature and light intensity, as phytoplankton are photosynthetic organisms that require light and warmth to grow and reproduce. However, phytoplankton can grow in areas of low nitrogen concentration, as long as there is sufficient availability of other essential nutrients, such as phosphorus and carbon. Phytoplankton are able to obtain nitrogen from a variety of sources, including nitrogen gas in the atmosphere and dissolved nitrogen compounds in the water. Therefore, statement 2 is incorrect.
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