A chromosome in which the centromere is situated close to its end so that one arm is veryshort and the other very long is :

Options

A. Acrocentric
B. Metacentric
C. Sub-metacentric
D. Telocentric

Answer

To solve the question, we need to identify the type of chromosome based on the position of the centromere. The question states that the centromere is situated close to the end, resulting in one arm being very short and the other very long. Let's break down the solution step by step:

### Step 1: Understand the Structure of Chromosomes
Chromosomes are made up of two arms (the short arm and the long arm) and a centromere that connects these arms. The position of the centromere can vary, leading to different classifications of chromosomes.

**Hint:** Remember that the centromere is the point where the two chromatids are joined and its position determines the type of chromosome.

### Step 2: Identify Types of Chromosomes Based on Centromere Position
There are four main types of chromosomes based on the location of the centromere:
1. **Metacentric**: Centromere is in the middle, resulting in two equal arms.
2. **Submetacentric**: Centromere is slightly off-center, leading to one arm being longer than the other, but not extremely different.
3. **Acrocentric**: Centromere is located closer to one end, resulting in one very short arm and one very long arm.
4. **Telocentric**: Centromere is at the very end of the chromosome, resulting in one arm being absent or very short.

**Hint:** Focus on the descriptions of each type to determine which one fits the criteria of having one very short arm and one very long arm.

### Step 3: Analyze the Given Information
The question specifies that the centromere is "situated close to its end," which suggests that the chromosome in question has one arm that is significantly shorter than the other. This description aligns with the characteristics of an acrocentric chromosome.

**Hint:** Pay attention to the wording "close to its end" as it indicates a position that is not at the very end but still significantly off-center.

### Step 4: Conclusion
Based on the analysis, the type of chromosome where the centromere is situated close to its end, resulting in one very short arm and one very long arm, is classified as an **acrocentric chromosome**.

**Final Answer:** The chromosome in which the centromere is situated close to its end so that one arm is very short and the other very long is called an **acrocentric chromosome**.