This pathway outlines the process of genetic engineering with a focus on gene cloning. This pathway also provides an introduction for the ABE lab series.
Learn genetics and inheritance works on a molecular level.
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Natural selection acts on the phenotype (traits or characteristics) of an individual. On the other hand, natural selection does not act on the underlying genotype (the genetic makeup) of an individual. For many traits, the homozygous genotype, AA, for example, has the same phenotype as the heterozygous Aa genotype. If both an AA and Aa individual have the same phenotype, the environment cannot distinguish between them. So natural selection cannot select for a homozygous individual over a heterozygous individual. Even if the "aa" phenotype is lethal, the recessive a allele, will be maintained in the population through heterozygous Aa individuals. Furthermore, the mating of two heterozygous individuals can produce homozygous recessive (aa) individuals. Learn more about evolution acts on the phenotype in this learning module produced by CK-12.
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Mendel laid the foundation for modern genetics, but there were still a lot of questions he left unanswered. What exactly are the dominant and recessive factors that determine how all organisms look? And how do these factors work? Learn more about modern genetics in this learning module produced by CK-12.
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This resource explains Mendel's first law (Law of Segregation) in detail. Includes Mendel's original experiments with results and conclusions.
Psychology is designed to meet scope and sequence requirements for the single-semester introduction to psychology course. The book offers a comprehensive treatment of core concepts, grounded in both classic studies and current and emerging research. The text also includes coverage of the DSM-5 in examinations of psychological disorders. Psychology incorporates discussions that reflect the diversity within the discipline, as well as the diversity of cultures and communities across the globe.Senior Contributing AuthorsRose M. Spielman, Formerly of Quinnipiac UniversityContributing AuthorsKathryn Dumper, Bainbridge State CollegeWilliam Jenkins, Mercer UniversityArlene Lacombe, Saint Joseph's UniversityMarilyn Lovett, Livingstone CollegeMarion Perlmutter, University of Michigan
By the end of this section, you will be able to:
Explain the basic principles of the theory of evolution by natural selection
Describe the differences between genotype and phenotype
Discuss how gene-environment interactions are critical for expression of physical and psychological characteristics
Bonnie Chen builds on students' prior knowledge of mutations to lead her class through a simulation of wading birds feeding. [14:02]
This illustration from Evolution by Monroe W. Strickberger shows the remarkable similarities between the bones in the forelimbs of various tetrapods, all of whose limbs serve very different functions.