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Mendelian and Extensions of Mendelian Genetics - Coggle Diagram
Mendelian and Extensions of Mendelian Genetics
Pea plant
there are many varieties
large number of offspring from each mating
could strictly control mating between plants
short generation time
true-breeding varieties self-fertilisation
Modern genetic terminology
Homozygous alleles
Identical alleles for specific gene
Heterozygous alleles
non-identical alleles for a specific gene
Dominant alleles
Identical alleles for specific gene
Recessive alleles
Identical alleles for specific gene
Genotype
The allelic complement of the organism, the genes
Phenotype
outward appearance of the organisms or other characteristics
the result of the genes
Law
Law of segregation
two alleles for a heritable character segregate during gamete formation and end up in different gametes
Crossing pea plants
Application
crossing, or mating, two-breeding varieties of an organism,
Results
the same for the reciprocal cross
Applications of Mendel's Principle
Punnett Square
straightforward way of predicting the outcome o crosses
predicting the allele composition of offspring from a cross between individuals of known genetic makeup
Law of independent assortment
Mendel worked out the second law of inheritance by following two characters at the same time
each pair of alleles segregates independently of any other pair of alleles during gamete formation
Extensions of Mendelian Genetics
Incomplete dominance
neither allele is completely dominant, and the F1 hybrids have a Phenotype somewhere between those of the two parental varieties
Codominance
the two alleles each affect the phenotype in separate, distinguishable ways
Multiple alleles
only two alleles exist for the pea characters that Mendel studied, but most genes exist in more than two allelic forms
Sex-influenced inheritance
specific in one sex, but are not sex linked
not on X chromosome
controlled by a pair of chromosome
found on the autosome
Sex-limited inheritance
occur only in one of the two sexes and are generally autosomal traits that are visible only in one sex
Sex-linked inheritance
found on one of the two types of sex chromosomes but not on both
only 1 copy is present in an individual