Test crosses are performed to determine the genotype of an organism. A farmer buys a goat whose owner claims has sired fainting goats, though Gary has never actually fainted himself. What type of goat (genotype/phenotype) should the farmer mate with Gary to determine if Gary really is a carrier. Explain your reasoning showing the cross.

A goat that faints with a genotype (gg)

Explanation:

Ideally, test crosses are used in genetics to determine the genotype of an unknown organism (usually a dominant phenotype). In a case of goats with a fainting gene (G), the dominant allele is G while the recessive allele is g. G codes for no fainting while g codes for fainting in goats.

The farmer wants to ascertain whether Gary, a goat he bought, is indeed a carrier of the fainting trait or simply a heterozygous (Gg). He performs a test cross by crossing Gary (Gg) with a goat that is homozygous (gg) for the recessive phenotype (fainting). In this cross, if Gary were truly a carrier/heterozygous, half (1/2) of the offsprings produced will be phenotypically fainting goats with genotype (gg). If not, all offsprings will not express the fainting trait.

g g

G. Gg. Gg

g. gg. gg

the core of the sun is so hot and there is so much pressure, nuclear fusion takes place, hydrogen is changed to helium. nuclear fusion creates heat and photons. when the heat reaches the earth it warms the molecules of the atmosphere, and they warm other molecules and so on.