On earth, maximum amount of dry matter is synthesized by

Options

A. sea weeds
B. forest trees
C. diatoms and dinoflagillates
D. grasses and sedges

Answer

To answer the question "On earth, maximum amount of dry matter is synthesized by," we will follow these steps:

### Step 1: Understand the Concept of Dry Matter
- Dry matter refers to the mass of material remaining after all the water has been removed. It is an important measure in ecology as it reflects the biomass produced by organisms.

### Step 2: Identify the Organisms
- The question provides four options: seaweeds, forest trees, diatoms and dinoflagellates, and grasses and sedges. We need to evaluate which of these groups is known for synthesizing the maximum amount of dry matter.

### Step 3: Analyze Each Option
1. **Seaweeds**: These are marine algae that contribute to biomass but are not the primary producers of dry matter on a global scale.
2. **Forest Trees**: While they do produce significant biomass, they are primarily terrestrial and do not match the productivity of certain aquatic organisms.
3. **Diatoms and Dinoflagellates**: These are types of phytoplankton found in aquatic environments. They are highly productive and are known for their role in carbon fixation and oxygen production.
4. **Grasses and Sedges**: These are important producers in terrestrial ecosystems, but again, they do not surpass the productivity of aquatic phytoplankton.

### Step 4: Conclusion
- After analyzing the options, it is clear that diatoms and dinoflagellates, which are part of the phytoplankton community, synthesize the maximum amount of dry matter on Earth due to their high rates of photosynthesis and vast populations in oceans.

### Final Answer
The maximum amount of dry matter on Earth is synthesized by **diatoms and dinoflagellates** (Option 3).

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