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It is important that the centromere not ...

It is important that the centromere not divide till the end of metaphase because it -
(A)contains the genes that control prophase.
(B)holds the replicated DNA molecules together.
(C)is connected to the nuclear membrane
(D) produces the spindle fibers

A

A

B

B

C

C

D

D

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question regarding the importance of the centromere not dividing until the end of metaphase, we will analyze each option provided. **Step 1: Understand the role of the centromere.** The centromere is a region of the chromosome where the two sister chromatids are joined together. It plays a crucial role during cell division, particularly in ensuring that the chromatids are properly aligned and separated. **Step 2: Analyze the options.** - **(A) Contains the genes that control prophase.** - This option is incorrect because the centromere does not contain genes that control prophase. Prophase is primarily regulated by proteins and other factors, not by the centromere itself. - **(B) Holds the replicated DNA molecules together.** - This option is correct. The centromere is responsible for holding the sister chromatids together until they are ready to be separated during anaphase. If the centromere divides prematurely, the chromatids may not separate correctly, leading to unequal distribution of genetic material. - **(C) Is connected to the nuclear membrane.** - This option is incorrect. The centromere is not directly connected to the nuclear membrane. Instead, it is involved in the attachment of spindle fibers during cell division. - **(D) Produces the spindle fibers.** - This option is also incorrect. The spindle fibers are produced by the centrosomes, not the centromeres. The centromere serves as the attachment point for these fibers. **Step 3: Conclusion.** Based on the analysis, the correct answer is **(B) holds the replicated DNA molecules together.** This is crucial for ensuring that during cell division, each daughter cell receives the correct number of chromosomes. ---
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