When a combination of multiple gene pairs is responsible for a particular trait it is called?
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During the formation of gametes (eggs and sperm in people and pigeons), chromosomes go through a process called homologous recombination. Show
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First, the cell makes an identical copy of each chromosome. Identical copies are called sister chromatids, and they remain attached to one another for now. Next, all four copies—two identical copies of two homologous chromosome—line up next to one another, and they swap large sections of DNA. The DNA strands actually break and rejoin. After recombination, the chromosomes still have the same genes arranged in the same order, but the alleles have been rearranged. Finally, the chromosomes are divvied up so that each gamete gets just one copy of each chromosome. While each gamete ends up with one copy of every gene, they have different combinations of alleles for those genes. Recombination increases genetic diversity. The location of the chromosome break points is random (or nearly so), and each gamete receives a random copy of each recombined chromosome. All of this jumbling and mixing allows for a nearly infinite number of allele combinations. Recombination rearranges chromosomes, generating new allele combinations. While just one homologous chromosome pair is shown above, the same process happens for all of them. Polygenic Trait. As we've gotten better at identifying regions of the human genome that are associated with disease and at analyzing complicated genomic data, we've learned that the genetic component of many of the most important health conditions of our time — cancer, heart disease, diabetes — are due to the effects of multiple genes. Hence, polygenic, or many genes. This has been a fascinating area of study, as scientists have begun to study these conditions and realized that the ways that we have of predicting risks for polygenic traits have tremendous potential for improving human health.
In what inheritance a combination of multiple gene pairs is responsible for the production of a particular trait?Polygenic inheritance is also involved in quantitative traits, in which multiple gene loci each contribute in a similar way to the phenotype so that the total number of contributing alleles determines the phenotype. What is multiple inheritance in genetics?Multifactorial inheritance is when more than 1 factor causes a trait or health problem, such as a birth defect or chronic illness. Genes can be a factor, but other things that aren't genes can play a part, too. These may include: Nutrition. Lifestyle. What is the combination of genes for a trait?Within an individual organism, the specific combination of alleles for a gene is known as the genotype of the organism, and (as mentioned above) the physical trait associated with that genotype is called the phenotype of the organism. What is an example of multiple gene inheritance?Polygenic Inheritance: Human skin color is a good example of polygenic (multiple gene) inheritance. Assume that three "dominant" capital letter genes (A, B and C) control dark pigmentation because more melanin is produced. What is a combination of genes called?Definitions. Genetic recombination refers to the rearrangement of DNA sequences by the breakage and rejoining of chromosomes or chromosome segments. It also describes the consequences of such rearrangements, that is, the inheritance of novel combinations of alleles in the offspring that carry recombinant chromosomes.
What is it called when a group of gene pairs act together?***polygenetic inheritance. Occcurs when many gene pairs act together to produce a single trait. Occurs when a group of gene pairs acts together and produces a specific trait, such as human eye color, skin color, or height. ***sex-linked gene.
How do you call the pairs of genes that carry the same traits?The combination of alleles that an organism carries constitutes its genotype. If the paired alleles are the same, the organism's genotype is said to be homozygous for that trait; if they are different, the organism's genotype is heterozygous.
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