Which refers to the loss of a portion of the chromosome?
Deletions: A portion of the chromosome is missing or deleted. Duplications: A portion of the chromosome is duplicated, resulting in extra genetic material. Translocations: A portion of one chromosome is transferred to another chromosome. There are two main types of translocation.
When homologous chromosomes fail to separate during meiosis This is termed?
Nondisjunction in Meiosis: Nondisjunction occurs when homologous chromosomes or sister chromatids fail to separate during meiosis, resulting in an abnormal chromosome number.
What is it called when you have an extra chromosome?
A medical term for having an extra copy of a chromosome is ‘trisomy. ‘ Down syndrome is also referred to as Trisomy 21. This extra copy changes how the baby’s body and brain develop, which can cause both mental and physical challenges for the baby.
Which genetic disorder is the result of a deletion of a section of an individual’s chromosome?
Cri du chat syndrome – also known as 5p- syndrome and cat cry syndrome – is a rare genetic condition that is caused by the deletion (a missing piece) of genetic material on the small arm (the p arm) of chromosome 5.
When a portion of a chromosome breaks off and attaches to a different chromosome This is called a?
Translocations. A translocation occurs when a piece of one chromosome breaks off and attaches to another chromosome. This type of rearrangement is described as balanced if no genetic material is gained or lost in the cell.
When homologous chromosomes fail to separate during meiosis This is termed quizlet?
Nondisjunction refers to the failure of pairs of chromosomes or sister chromatids to separate during meiosis or mitosis. You just studied 28 terms!
What term refers to turning a chromosome segment around 180 and rejoining it to the original chromosomes?
An inversion occurs when a chromosome breaks in two places and the region between the break rotates 180° before rejoining with the two end fragments.
When homologous pairs of chromosomes fail to separate during gamete formation What occurs?
The phenomenon of unequal separation in meiosis is called nondisjunction. If nondisjunction causes a missing chromosome in a haploid gamete, the diploid zygote it forms with another gamete will contain only one copy of that chromosome from the other parent, a condition known as monosomy.
What causes an extra chromosome?
The addition of an extra chromosome usually occurs spontaneously during conception. The cause of this is unknown and prevention is not possible. The most important risk factor for trisomy conditions is maternal age. Women in their late 30s and 40s have a higher chance of trisomy conditions occurring.
What causes XXY chromosome?
Males have an X and a Y sex chromosome (XY). Klinefelter syndrome can be caused by: One extra copy of the X chromosome in each cell (XXY), the most common cause. An extra X chromosome in some of the cells (mosaic Klinefelter syndrome), with fewer symptoms.