Structure Functions and Types of centromere Quiz

The centromere is the region of the chromosome where the two sister chromatids are attached. During cell division, the centromere plays a crucial role in ensuring the proper separation of chromatids to form two daughter cells. It acts as a binding site for proteins that help in the attachment of spindle fibers, which are responsible for pulling the chromatids apart. Therefore, the correct answer is that chromatids are attached at the centromere.

Telomeres are the ends of the chromosome. They consist of repetitive DNA sequences that protect the chromosome from degradation and prevent the loss of important genetic information during DNA replication. Telomeres also play a crucial role in cell division and senescence. Centromeres, on the other hand, are regions in the chromosome that are responsible for the attachment of spindle fibers during cell division. Satellites refer to specific regions of the chromosome that have a different composition or structure compared to the rest of the chromosome. Therefore, the correct answer is Telomeres.

A chromosome with a centromere near the middle is called submetacentric. This means that the two arms of the chromosome are unequal in length, with one arm being longer than the other. The centromere is not exactly in the middle, but closer to one end. This type of chromosome is commonly found in many organisms, including humans.

Chromosomes are condensed to provide cell division in daughter cells. During cell division, the condensed chromosomes ensure that each daughter cell receives the correct number and type of chromosomes. Condensation allows the chromosomes to become more compact and organized, making it easier for them to be distributed evenly between the daughter cells. This ensures the accurate transmission of genetic information and helps maintain the integrity of the cell's DNA.

Centromeric DNAs were previously identified in yeast. This suggests that yeast, along with other organisms such as bacteria, humans, and fungi, have centromeric DNAs. However, the question specifically asks for the earlier identification, implying that yeast was one of the first organisms in which centromeric DNAs were discovered.

Waldeyer is credited with coining the term "chromosome" in 1888. He used the term to describe the thread-like structures that are visible in the nucleus of cells during cell division. This discovery was significant in advancing the understanding of genetics and the role of chromosomes in heredity. Boveri and Hoffmeister were also notable scientists in the field of cytology, but they did not coin the term "chromosome".

Yeast centromeres typically consist of three satellite sequence elements. These elements play a crucial role in ensuring proper chromosome segregation during cell division. Each element contains a specific DNA sequence that binds to proteins involved in centromere function. The presence of three elements allows for the formation of a stable and functional centromere, ensuring accurate chromosome segregation and maintenance of genomic stability.

This statement is false. Centromeric proteins are not the ones that connect to the spindle fibers. Instead, centromeric proteins are responsible for holding sister chromatids together and ensuring their proper alignment during cell division. The spindle fibers, on the other hand, attach to the centromeres and help separate the sister chromatids during mitosis or meiosis. Therefore, the correct answer is false.

Centrioles are critically responsible for the even distribution of parental DNA during cell division. They play a key role in forming the spindle fibers, which are responsible for separating the duplicated chromosomes. The spindle fibers attach to the centromere of each chromosome and pull them apart, ensuring that each new cell receives an equal and complete set of DNA. Without centrioles, the chromosomes would not be properly aligned and distributed, leading to genetic abnormalities in the resulting cells. Therefore, centrioles are essential for maintaining the genetic integrity and even distribution of parental DNA.

The centromere is the region of a chromosome that plays a crucial role in ensuring the even distribution of genetic material during cell division. It facilitates the attachment of spindle fibers, which are responsible for pulling apart sister chromatids and ensuring that each daughter cell receives an equal amount of genetic material. Therefore, the option "Facilitates even distribution" is the most suitable description for the centromere.