Lab practical 3: mendelian genetics powerpoint Flashcards
A human baby begins with the fusion of a haploid egg and a haploid sperm to form a ___.
___ are determined from the combination of the chromosomes from the maternal and paternal chromosomes.
diploid zygote
inherited characteristics
the genetic information that determines hereditary traits is found in the structure of the ___
a short segment of DNA that codes for a particular protein constitutes a ___
DNA molecules in the chromosmes
gene (both genes and chromosomes occur in homologous pairs)
in the simplest situation, an inherited trait such as flower color, is determined by a single pair of genes. The members of a ___ may be identical
alternate forms of a gene are called __
gene pair
alleles
When both members of a gene pair consist of the same allele, such as PP or pp, the individual is ___
When the members of a gene pair consist of unlike alleles, such as Pp, the individual is ___ or ___.
if heterozygous for two traits, the individual is ___.
homozygous (true breeding)
heterozygous or hybrid
dihybrid
the genetic composition of the gene pair (ex: PP, Pp, or pp) is referred to as the ___
the observable (expressed) form of a trait (ex: purple or white flowers) is called the ___
genotype
phenotype
An understanding of inheritance patterns enables the prediction of an ___ for the occurrence of a trait in the progeny (offspring) of parents of known genotypes.
expected ratio
The ___ states that (a) genes occur in pairs and exist unchanged in the heterozygous state, and (b) members of a gene pair are segregated (seperated) from each other during gamete formation by meiosis, ending up in seperate gametes.
principle of segregation
The ___ states that genes for one trait are assorted (segregated into gametes) independently from genes for other traits. The principle applies only to genes that are located on different chromosome pairs (ex: genes that are non-linked)
principle of independent assortment
when a gene pair consists of two alleles and one of these alleles is expressed and the other is not, the expressed allele is said to be ___
the unexpressed allele is ___
dominant
recessive
genotype = ?
phenotype = ?
gento = 25%TT, 50%Tt, 25%tt
pheno = 75% tall, 25% not tall
___ is characterized by the expression of alternate alleles in the heterozygote, and the heterozygote’s phenotype appears as a “blended” intermediate between the phenotypes of the two homozygous parents.
incomplete dominance
___ is characterized by the expression of both alleles in the heterozygote, but no apparent blending occurs in the heterozygote phenotype. human blood type group characteristics are codominant. A person with type AB blood has the A and B allele on the surface of their red blood cells. A person with type O blood has neither A nor B on the surface of their blood cells.
codominace