Genetics Flashcards
Genetics:
The study of the patterns of inheritance, genes, and genetic variation.
Gregor Mendel:
Tracked and recorded the transmission of seven visible traits through several generations of pea plants.
P1:
The parental generation which crosses first.
F1:
The filial generation where the offspring from the first P cross.
Purebred:
Homozygous individuals.
Genes:
What traits are determined by.
Alleles:
The specific alternations between genes.
Dominant:
The stronger of the two alleles able to mask the other trait. Represented by a capital letter.
Recessive:
The allele that is masked by the more dominant allele represented by a lowercase letter.
The Principle of Dominance:
If one allele is dominant and the other is recessive, the dominant allele can override its potential influence over the recessive allele.
Diploid organisms have ___ allele(s) of every gene.
two
Homozygous:
When both alleles of a gene pair are the same.
Heterozygous:
When the alleles of a gene pair are different.
Genotype:
Two alleles put together.
Phenotype:
The physical expression of the genotype.
The Principle of Segregation:
Two copies of a gene pair undergo segregation during the formation of sex cells during meiosis.
The Principle of Independent Assortment:
Allele pairs separate independently during gamete formation, and traits are passed onto offspring independently of one another.
Incomplete Dominance:
A heterozygous organism that shows a blending of genes because neither gene is dominant. The result is a new phenotype.
Codominance:
When two different alleles contribute to a phenotype which results in both phenotypes showing up.
Autosome:
A chromosome not involved in sex determination.
Does the male or female determine the offspring’s sex?
The male.
Genes for sex-linked traits are carried on the _ chromosome but not the _ chromosome.
X, Y
Who discovered sex linkage?
Thomas Hunt Morgan.
Polygenic Inheritance:
When different genes interact to control the phenotypic expression of a single trait.
Epistasis:
When the allele of one gene suppresses the action of an allele of another gene.
Simple Interaction:
When two or more genes affect the same characteristic.
Pedigrees:
A family tree in which the inheritance of a trait can be traced from parents to offspring.
What are the six mechanisms of inheritance for pedigrees?
Autosomal dominant, autosomal recessive, sex-linked recessive, sex-linked dominant, Y-link, and mitochondrial.
Linked genes:
Genes found on the same chromosome. Independant assortment does not occur during gamete formation.
Genes located (farther from/closer to) each other cross over at higher frequencies.
farther from
