Heredity vs Variation
Heredity and variation are two closely related terms ingeneticsthough, there is a subtle difference between heredity and variation, which has to be understood carefully. Heredity is the passing of characters of parents to their offspring. A progeny can inherit characters either bysexual or asexual reproduction. On the other hand, variation is the process of the changes occurring, or the differences of the inherited characteristics. These variations can be the results ofgenetic variationor environmental variation.
What is Heredity?
每种生物体都是通过性或无性繁殖繁殖其母体生物的结果。在无性繁殖中，个体从父母那里获得完全相似的遗传组成。而在性繁殖中，一半genes来自母亲，另一半来自父亲。因此，后代比其他无关的人更像他们的父母。这个phenomenon of offspring inheriting their genes from parentsis known as heredity.
但是，后代phenotypeor external appearance of an individual is determined by its genetic composition (genotype; G) and environment (E) in which they live (P = G + E).例如。Some tall plants become stunted when they are in harsh environments that may lack water and other nutrients.
The above described inherited characters are calledhereditary characters.
遗传是后代从父母那里继承了基因
What is Variation?
Variation can be identified as人群中个体特征的差异. Discrete variations and continuous variations are two types of variations.
Discrete variations– discrete variations can be demarcated by their distinct nature. These types of traits are governed by one or a few genes, and the impact of environment on gene expression is very less.
例如。特质眼颜色具有离散的变化，例如棕色，蓝色。
Ear lobe of a person can be attached or free.
Continuous variations– these types of variations show continuously changing values or data for the selected character. Therefore, these types of traits are governed by multiple genes or polygenes. Thus, it is also known as polygenic character. The environment is highly influenced by the character expression.
例如。Height of a person or a plant.
Continuous characters can be represented using frequency distribution curves.
个体的表型变化是遗传和环境变异的结果。由于人群的遗传变异mutation, recombination, and gene flow. Mutation is the permanent change of anucleotidesequence of an organism. If this change occurs in a coding region, products of the gene become different (e.g. DDT resistance mosquitos resulted due to mutation). Recombination is the process of exchanging genetic material between non-sister chromatids. As a result,gametesproduced by single cell division cycle become unique to one another. Gene flow occurs when an individual organism moves into a new population. It increases the variation in alleles in the population.
成人骨头大麻片显示背色变化
有什么异同Heredity and Variation?
•遗传和变异的定义：
• Heredity is the passing of characters from one generation to another.
• Variation is the differences present in characters exhibited organisms.
• Phenotypic Characters:
• Both heredity and variation include the phenotypic characters of an organism.
• Environment and Genotype Influence:
• Both heredity and variation are influenced by the genotype of an organism and the environment in which the organism lives.
• Importance in Evolution:
• Both heredity and variation are important in evolution; fornatural selection.
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