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Found Phenotype 41 times.

Displaying results 1 to 10.

1. Biometrical genetics
The mathematical approach to the study of the inheritance of different phenotype s, or physical characteristics, as a result of plant or animal breeding.

2. Cis configuration
* The configuration of an organic molecule containing a double bond between two carbon atoms, where the largest, most complex R group s are on the same side: -OR- The configuration of an organic molecule containing a ring, where the largest, most complex R groups are on the same side: These configurations are the opposite of trans configuration . * A genetics term meaning an event or a gene whose action occurs on the same chromosome . * Two mutation s in different genes coding for the same phenotype which are on the same chromosome (as opposed to the trans configuration where each homologue has one of the mutations).

3. Cis-trans test (complementation test)
A lab test which is used to determine whether two mutation s of different gene s which affect the same phenotype are on the same functional unit (indicating a cis configuration of the mutated genes) or on different functional units (indicating a trans configuration of the mutated genes). (A functional unit can be a chromosome .) The test is done by mating an individual that has one of the mutations to an individual that has the other one, and observing whether their offspring have the mutant phenotype. If the offspring do not have the mutant phenotype, then the genes are known to be trans, because the offspring have normal copies of each mutant gene on the different functional units which are able to genetically complement each other. If the offspring do have the mutant phenotype, then the genes are known to be cis, because the offspring will always inherit at least one of the mutant genes on the one functional unit, resulting in the mutant phenotype.

4. Codominance (codominant genes)
Two allele s of a gene which result in distinctly different phenotype s, but when they are both inherited together in an individual (one from the mother and one from the father - called heterozygosity ), the individual has both of the phenotypes. For example, if one allele is for red hair and the other allele is for blue hair, then the individual will have patches of blue hair and patches of red hair. (This is in contrast to incomplete dominance , where the individual would inherit a blend of the two alleles and have purple hair).

5. Complete dominance
The type of inheritance in which both heterozygotes and dominant homozygotes have the same phenotype .

6. Continuous variation
Occurs when the phenotypes of traits controlled by a single gene cannot be sorted into two distinct phenotypic classes, but rather fall into a series of overlapping classes.

7. Cryptic plasmid
A plasmid which has no apparent effect on the phenotype of its host cell and has no gene s other than the ones needed for itself to replicate and spread to other cells.

8. Directional selection
A process of natural selection that tends to favor phenotypes at one extreme of the phenotypic range.

9. Discontinuous variation
Occurs when the phenotypes of traits controlled by a single gene can be sorted into two distinct phenotypic classes.

10. Dominant
A gene is said to be dominant if it expresses its phenotype even in the presence of a recessive gene.


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