Genetics: Dominant and Recessive Alleles

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ConscientiousChrysanthemum
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6 Questions

¿Qué tipo de gen es más influyente cuando un organismo hereda una copia?

Un gen dominante

Si un individuo hereda una copia de un gen recesivo, ¿qué sucederá con la expresión de ese rasgo?

El rasgo dominante se expresará

¿Cuál es el requisito para que un rasgo recesivo se exprese en un individuo?

Heredar dos copias del gen recesivo

¿Cuál es un ejemplo de un rasgo dominante?

Ojos azules

¿Qué sucede cuando un individuo es portador de un gen recesivo para una enfermedad?

No desarrollará la enfermedad

¿Qué tipo de gen es menos influyente cuando un organismo hereda solo una copia?

Gen recesivo

Study Notes

Genetics: Understanding Dominant and Recessive Alleles

Genetics is the study of heredity and variation in organisms from generation to generation. It involves understanding how traits are passed down through DNA, which contains all the genetic information necessary to develop and function properly. Two main types of genes control these traits: dominant and recessive alleles.

Dominant Alleles

A gene has two versions or variants called alleles. One allele may have a more significant effect on a particular trait, known as the dominant allele. If an organism inherits one copy of this dominant allele, it will express that trait; even if there's another allele with less impact, it won't change anything. For example, if someone inherits a dominant allele for blue eyes, they will have blue eyes regardless of any other eye color alleles they might also carry.

Recessive Alleles

On the other hand, the second type of gene variant is referred to as a recessive allele. When an individual carries only one copy of a recessive allele, the dominant allele suppresses its expression, and the person does not show the recessed characteristic. However, when both copies of the gene are recessive, the person usually exhibits the recessive trait. An example of this would be cystic fibrosis, where carriers have one normal gene and one defective gene. Neither the carrier nor their offspring gets sick because the dominant healthy gene controls the disease. But the risk exists if the partners exchange gametes, each potentially carrying a faulty CF gene.

The expression of recessive alleles can lead to various conditions, such as cystic fibrosis, which affects approximately 30,000 people worldwide. In contrast, dominant alleles typically result in what we observe as different physical characteristics, like hair color or eye shape.

In conclusion, genetics is a complex field that deals with the inheritance of specific traits through our genetic makeup. Understanding dominant and recessive alleles helps us comprehend how different characteristics pass down from parents to their offspring, shaping the diverse range of phenotypes observed in nature.

Learn about how dominant and recessive alleles control the expression of traits in organisms through the study of genetics. Discover how these different gene variants interact to influence an individual's phenotype and inheritance patterns.

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