different between testcross vs backcross

English

Alternative forms

• test cross

Etymology

test +? cross

Pronunciation

• IPA^(key): /?t?st?k??s/

Noun

testcross (plural testcrosses)

1. (genetics) The breeding of an individual with a phenotypically recessive individual, in order to determine the zygosity of the former by analysing proportions of offspring phenotypes.
   • 1967, W. A. Russell, A. H. Teich, Selection in Zea Mays L. by Inbred Line Appearance and Testcross Performance in Low and High Plant Densities

     The inbreds of groups 3 and 4 have a distinct difference in plant height, except for a few selections, presumably because of some difference in selection pressure at low- and high-stand densities. Group means for testcross performance showed more progress in group 4 than in group 3 because of a difference in the number of low-yielding genotypes in the two groups.

   • 2012, Benjamin A. Pierce, Genetics: A Conceptual Approach, Macmillan (?ISBN), page 55

     You could determine its genotype by performing a testcross. If the plant were homozygous (TT), a testcross would produce all tall progeny (TT × tt ? all Tt); if the plant were heterozygous (Tt), half of the progeny would be tall and half would be short (Tt × tt ? 1/2 Tt and 1/2 tt). When a testcross is performed, any recessive allele in the unknown genotype is expressed in the progeny, because it will be paired with a recessive allele from the homozygous recessive parent.

Anagrams

• Crossetts

English

Etymology

back +? cross

Verb

backcross (third-person singular simple present backcrosses, present participle backcrossing, simple past and past participle backcrossed)

1. (genetics) To cross a hybrid with one of its parents.

Noun

backcross (plural backcrosses)

1. (genetics) The act of crossing a hybrid with one of its parents.
2. (genetics) An organism produced by such a crossing.
3. (juggling) Alternative form of back cross

Anagrams

• crossback