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In the mid-19th century, the study of inheritance as a modern branch of science began with the work of..
Offspring from the P generation are heterozygous; they are called the F1 or ________ generation
A ______________ gene may mask the expression of a _______________________ gene.
During meiosis, members of paired genes at each allele _______________ so that each gamete contains only one allele of each pair.
An individual is said to ____________ for a particular feature when the two alleles it carries for that feature are different
A ______________ predicts the ratios of genotypes and phenotypes of the offspring of a cross
A test cross is a cross between an individual of unknown genetic composition and a ______________________ individual.
A dihybrid cross is a cross between individuals that differ with respect to their alleles at _____________
The chromosome theory of inheritance can be explained by assuming that genes are ___________________ in specific locations along the chromosomes
The sex or gender of many animals is determined by the X and Y sex chromosomes. The other chromosomes in a given organism's genome are called ____________
When a Y-bearing sperm fertilizes an ovum, the result is a _________________ and fertilization by an X-bearing sperm produces a ________________
XY zygote; XX zygote
A dense, metabolically inactive X chromosome at the edge of the nucleus in female mammalian cells is known as the ________________
In genetic crosses involving _________, the genotypic and phenotypic ratios are identical
_____________ refers to the many different effects that can often result from a given gene
________________ is when one allele of a gene pair detemines whether alleles of other gene pairs are expressed
It is called ____________ when two or more independent pairs of genes have similar and additive effects on a phenotype
The range of phenotypic possibilities that can develop from a single genotype under different environmental conditions is known as the ________________
norm of reaction
Condition in which certain alleles at one locus can alter the expression of alleles at a different locus
A condensed and inactivated X-chromosome appearing as a distinctive dense spot in the nucleus of certain cells of female mammals
The differences between parents and offspring or among individuals of a population
members of two different true-breeding lines that are crossed to produce the F1 generation; parental generation
the first generation of hybrid offspring resulting from a cross between parents from two different true-breeding lines; first filial generation
States that before sexual reproduction occurs, the two alleles carried by an individual parent must become separated
Principle of segregation
the possible combinations of eggs and sperm at fertilization can be represented in the form of this grid
states that members of any gene pair segregate from one another independently of the members of the other gene pairs
principle of independent assortment
the tendency for a group of genes on the same chromosome to be inherited together in successive generations
the observation of linkage in the results of a test cross and because alleles of two love are involved
a condition in which neither member of a pair of contrasting alleles is completely expressed when the other is present
the condition which three or more alleles for a given locus exist within the population
a common type of gene interaction in which the presence of certain alleles of one locus can prevent or mask the expression of alleles of a different locus and express their own phenotype instead
when multiple independent pairs of genes have similar and additive effects on the same character
A person with one X but no Y chromosome has the overall appearance of a female but has defects such as short statue and undeveloped ovaries
A person with an XXY constitution is a nearly normal male in external appearance, although his testes are underdeveloped
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