Unit 9: What is Heredity?
the father of genetics
Mendel is know for ____?
trait
a physical characteristic of an organism.
F1 (first filial) generation
all offspring were tall.
organism traits
controlled by the alleles it inherits from its parents. Some alleles are Dominant the other Alleles are recessive.
allele
different forms of a gene
Mendel's 2nd conclusion
factors that control each trait occurs in pairs. The female parent contributes one factor, while the male parent contributes another.
pollination
fertilization in plants.
recessive allele
hidden whenever the dominant allele is present.
Mendel's 1st conclusion
individual factors, or set of genetic information must control the inheritance of traits in peas.
fertilization
occurs when sperm and egg cells join.
Mendel's 3rd conclusion
one factor in a pair can mask, or hide, the other factor
dominant allele
one whose traits always shows up in an organism when the allele is present.
hybrid
organism that has two different alleles for a trait.
purebred
organisms that are "pure" for a specific trait
P (parent) generation
purebred tall plants were crossed with purebred short plants.
F2 (second filial) generation
three fourths of the offspring were tall; one fourth were short.
mendel found that only one form of the trait appeared in the F1 generation. In the F2 generation the "lost" form of the trade always reappeared in about one fourth of the plants
what happened in Mendel's crosses?
gene
a factor that controls traits
a dominate a allele is represented by an uppercase letter (T) and it's recessive a allele is represented by the same letter but lower case (t). A dominant and recessive a allele is represented by an uppercase letter and a lowercase letter (Tt).
symbols used to represent the alleles?
heredity
the passing of physical characteristics from parent to offspring.
genetics
the scientific study of heredity.