DNA polymerase required for synthesising copies of DNA at high temperature is obtained from

Options

A. Thermus aquaticus
B. Cephalosporium gramineum
C. Bacillius megatherium
D. Thermoproteus species.

Answer

To answer the question, "DNA polymerase required for synthesising copies of DNA at high temperature is obtained from?", we will follow these steps:

### Step 1: Understand the Role of DNA Polymerase
DNA polymerase is an enzyme that synthesizes new strands of DNA by adding nucleotides to a pre-existing strand. It is essential for DNA replication and is particularly important in techniques like the Polymerase Chain Reaction (PCR).

**Hint:** Remember that DNA polymerase is crucial for DNA replication and synthesis.

### Step 2: Identify the Type of DNA Polymerase Needed
The question specifies that we need a DNA polymerase that can function at high temperatures. This type of enzyme is often referred to as "thermostable" DNA polymerase. The most commonly used thermostable DNA polymerase in molecular biology is Taq DNA polymerase.

**Hint:** Look for enzymes that can withstand high temperatures, especially in PCR applications.

### Step 3: Know the Source of Taq DNA Polymerase
Taq DNA polymerase is derived from the bacterium Thermus aquaticus, which thrives in hot springs and other high-temperature environments. This bacterium is known for its ability to survive and function at elevated temperatures, making it an ideal source for DNA polymerase used in PCR.

**Hint:** Consider organisms that live in extreme environments, particularly those that are thermophilic.

### Step 4: Evaluate the Options Given
The options provided are:
- A) Thermus aquaticus
- B) Cephalosporium minimum
- C) Bacillus megatherium
- D) Thermoproteus species

From the understanding gained:
- **Thermus aquaticus** is the correct answer as it is the source of Taq DNA polymerase.
- **Cephalosporium minimum** is a type of fungus and not a source for DNA polymerase.
- **Bacillus megatherium** is a non-pathogenic bacterium and does not produce the required DNA polymerase.
- **Thermoproteus species** are thermophilic archaebacteria but are not the source of the DNA polymerase used in PCR.

**Hint:** Cross-reference the options with the known sources of DNA polymerase.

### Conclusion
The correct answer to the question is **A) Thermus aquaticus**.

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