How do you determine genetic variation?
Genetic variation can also be identified by examining variation at the level of enzymes using the process of protein electrophoresis. Polymorphic genes have more than one allele at each locus.
How do genetic and environmental factors determine phenotypes?
Environmental factors such as diet, temperature, oxygen levels, humidity, light cycles, and the presence of mutagens can all impact which of an animal’s genes are expressed, which ultimately affects the animal’s phenotype.
What is variation in genotype caused by?
Genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism’s offspring).
How would you prove that genes interact with the environment to shape phenotype?
Molecular analyses The often used method to detect gene–environment interactions is by studying the effect a single gene variation (candidate gene) has with respect to a particular environment. Single nucleotide polymorphisms (SNP’s) are compared with single binary exposure factors to determine any effects.
What causes environmental variation?
Environmental causes of variation Characteristics of animal and plant species can be affected by factors such as climate, diet, accidents, culture and lifestyle. Another example is that of a plant that grows in the shade of a big tree – it will grow taller to reach more light.
What are the causes of variation?
Major causes of variation include mutations, gene flow, and sexual reproduction. DNA mutation causes genetic variation by altering the genes of individuals in a population. Gene flow leads to genetic variation as new individuals with different gene combinations migrate into a population.
How does a genotype become a phenotype?
Genotype & Phenotype. Definitions: phenotype is the constellation of observable traits; genotype is the genetic endowment of the individual. Phenotype = genotype + development (in a given environment). In a narrow “genetic” sense, the genotype defines the phenotype.
Is genotype influenced by the environment?
Genotype generally remains constant from one environment to another, although occasional spontaneous mutations may occur which cause it to change. However, when the same genotype is subjected to different environments, it can produce a wide range of phenotypes.
What is environmental variation?
the ability of an organism to alter greatly its PHENOTYPE depending upon environmental conditions. The phenomenon is seen most clearly in plants, perhaps because they are fixed in the ground.
How do genes interact with environmental factors?
In many genes, different variants (genotypes), alter the expressed outcomes (phenotype) even when exposed to the same environmental exposure. When health outcomes differ by genotype and require one or more environmental stimuli, the health outcome is said to result from a gene-environment interaction.
How do genes interact with environmental factors that affect behavior?
Genes, via their influences on morphology and physiology, create a framework within which the environment acts to shape the behavior of an individual animal. The environment can affect morphological and physiological development; in turn behavior develops as a result of that animal’s shape and internal workings.
What are the two main causes of variation?
The two main causes of variation are mutation and genetic recombination in sexual reproduction.
How do environmental and genetic factors affect phenotypic variation?
Both environmental and genetic effects contribute to phenotypic variation within and among populations. Genetic differentiation of quantitative traits among populations has been shown in many species, yet it can also be accompanied by other genetic changes, such as divergence in phenotypic plasticity and in genetic variance.
What are the sources of genetic variation in a species?
Genetic variation within a species can result from a few different sources. Mutations, the changes in the sequences of genes in DNA, are one source of genetic variation. Another source is gene flow, or the movement of genes between different groups of organisms.
What determines the genotype of a trait?
The genotype that an individual possesses for a trait, in turn, determines the phenotype —the observable characteristics—such as whether that individual actually ends up with straight, wavy, or curly hair. Genetic variation within a species can result from a few different sources.
How do alleles contribute to genetic variation?
Additionally, genes can exist in slightly different forms, called alleles, which further adds to genetic variation. The combination of alleles of a gene that an individual receives from both parents determines what biologists call the genotype for a particular trait, such as hair texture.