ipl-logo

How Does Chromosome Fusions Increase The Number Of Chromosomes

913 Words4 Pages

Chromosome “fusions” in Karyotype Evolution
Most of the genetic material in an organism is found in its chromosomes. The number of chromosomes in eukaryotic organisms can range from 1 to 600 for each haploid genome. Haploid genomes consist of genes that make up a set of chromosomes in a haploid cell, which contains of one set of chromosomes. Whereas in diploid cells, there are two sets of chromosomes. The characteristics of these chromosomes in a species is called a karyotype. The number of chromosomes in a species is usually unique to that species or population. However, it can increase or decrease by certain processes (Lysák, 1).
Chromosomes can increase in two ways, polyploidy and centric fusion. Polyploidy is the duplication of a chromosome set or sets, whereas in centric fusion, the centromere breaks and allows the original chromosome to split into two chromosomes. When the number of chromosomes decreases, it is called aneuploidy. This is caused when chromosomes or chromatids, one of the chromosome strands, separates incorrectly during cell division. The number of chromosomes can also be decreased as a result …show more content…

These chromosomes contain two centromeres, but they will only survive if one of the centromeres becomes inactive. If the two centromeres remain active and stay close together, they can turn into monocentric chromosomes. Although it has not been proved why the loss of centromeres occurs, it is believed to occur because of changes in gene expression. A possible reason that centromeres become inactive is because there is a loss of centromere-specific sequences. The changes in gene expressions happen with or after the removal of centromere-specific sequences. This is called centromere decay. However it undetermined how and when these centromeric sequences are removed (Lysák,

Show More
Related

Nt1310 Unit 1 Writing Assignment

852 Words | 4 Pages

In which case, the nuclear envelope is visible again and the DNA uncoil into chromatin. No DNA replication occurs during interphase II. In prophase II, the nuclear envelope disintegrates again, and the chromosomes stay in sister chromatid form (if they unraveled into chromatin during interphase II they condense again). In metaphase II, spindle fibers from opposing poles of the cell attach to the centromeres of each sister chromatid. Sister chromatids are two identical copies/strands connected by one centromere that results from the replication of a chromosome during the S phase.

Read More

Nt1310 Lab 1

401 Words | 2 Pages

In transcription, DNA polymerase unwinds DNA and makes the

Read More

Unit 8 Dna Research Paper

910 Words | 4 Pages

The same region is also amplified on both chromosomes, however they are different sizes, which are then put into gel

Read More

Fruit Fly Lab Report

1120 Words | 5 Pages

They are model organism’s for genetical experiments due to their fast generation time, size, reproductive abilities and well-defined genetics. They have only four chromosomes, known as 1(X), 2, 3, and 4. Chromosome one is a

Read More

Maria Lab Report

770 Words | 4 Pages

This entails the active generation of DNA double

Read More

Fruit Flies Lab Report

2825 Words | 12 Pages

Genes, or sometimes called alleles, are the small subunits that make up DNA and create the unique traits for each species. The type of genes that are replicated and passed down during DNA replication are called alleles and these combine when forming a new offspring to yield a new combination of traits. In most cases, alleles for a single trait are seen in pairs. The singular alleles within a pair can be classified as dominant or recessive, and whichever classification it falls under decides how the gene will be expressed. Dominant alleles are typically represented with a capital letter and they are traits that will always be expressed, regardless of the other allele it is paired with.

Read More

Pathophysiology Worksheet

1028 Words | 5 Pages

Because these chromosomes determine the sex of an individual, they are also referred to as sex chromosomes. 2. The homologous may have the same number of chromosomes but the form of pairing may differ depending on what they may receive from each parent via the sperm and the other from the female parent via the egg cell (ovum). 3.

Read More

6. Explain Why Evolution Often Selects Traits That Promote Genetic Diversity

927 Words | 4 Pages

Extra autosomes and extra or missing sex chromosomes relate to errors in meiosis because they are the result of chromosomes failing to properly separate in meiosis. Deletions, duplications, inversions, and translocations relate to an error in meiosis because they are a consequence of homologous chromosomes failing to align correctly in meiosis or result from errors when crossing over occurs. 8. Could nondisjunction occur during mitosis? Compare and contrast the likely consequence of nondisjunction in mitosis vs.

Read More

Drosophila Genetics Lab Report

1581 Words | 7 Pages

This is because the different chromosomes that the genres are on are independently assorted into daughter cells during meiosis (Updegraff,

Read More

Garlic Root Tip Lab Report

1393 Words | 6 Pages

The sister chromatids are pulled towards oppsite poles of the cell. (http://andrewhulse.weebly.com/archive-blog---life-in-room-213206209/archives/01-2014) Telophase:the chormatids are now called chormosomes. The nuclear envelope reforms arounds the two sets of chromosomes to form two new nuclei and in each nucleus the nucleolus reforms. The spindle fibres disappear and the chromosomes become uncoiled, elongated and are no longer visible.

Read More

Zebra Finch Lab Report

943 Words | 4 Pages

A possible way to test if a chromosome segment was affected by an inversion is to analyze the pattern of synapsis and crossing over in

Read More

Cat Eye Syndrome

995 Words | 4 Pages

Image: CES Karyotype affected Female (Caption: Karyotype of a CES affected female shows partial trisomy of chromosome 22 's long arm (22p)). Within the first few reports, CES was thought to have affected chromosome 13. In contrast to that belief, CES

Read More

Were Genetic Changes Random Back Then?

469 Words | 2 Pages

Not all changes took place at the same rate either. The X chromosome proved to be more stable than chromosome III and has remained large throughout evolution. The X chromosome is found twice in females and once in males, while the Y chromosome lost most of its genetic material early in its evolution and is found only once in males and not at all in females. The X chromosome has more than 1000 genes, while the Y chromosome has less than 200 genes. How might this happen?

Read More

Genetic Disorders

1026 Words | 5 Pages

Russell (2010) claims that the change in the chromosomal number and structure form of wild type condition is known as chromosomal mutation (p. 464). The wild type chromosomal complement consists of 46, XY for males and 46, XX for females. Chromosomal mutation occurs during the meiosis and mitosis, where the chromosomes complement is not an exact copies of 23 pairs at the end of the cell division. Two different type of zygote: trisomic (2n+1) and monosomic (2n-1) respectively produce when such gametes fuse with the wild type (Kumar et al., 2005). Whereas the structural changes in chromosome which causes by deletions, duplications, inversions and translocation are known as chromosomal structure mutation (Russell,

Read More

Summary: Two Common Types Of Genetic

936 Words | 4 Pages

Another type of mutation is named chromosome mutation and it happens due to the alternation in the structure and arrangement of chromosomes. This type of mutation can be detected and checked when there is change in the number of chromosomes of either there is a decrease or increase in numbers. Numerous types of diseases – Polydactyl, Sickle Cell Anaemia, Albino, Down syndrome and Turner syndrome are the result of cell mutation affecting the growth in children. Polydactyl is a disease that results in having more than five fingers or toes on each side.

Read More

More about How Does Chromosome Fusions Increase The Number Of Chromosomes

Related Topics

Open Document