A zygote is the first cell that results when an egg is fertilized by a sperm.
I hope this helps.
Answer:
Random segregation of homologous chromosomes makes the two siblings differ from each other for 0-23 chromosomes.
Explanation:
Sexual reproduction adds genetic variations in the progeny by crossing over, independent segregation of homologous chromosomes and random fusion of gametes. Without crossing over, independent segregation of homologous chromosomes towards opposite poles during anaphase I of meiosis may result in two siblings to vary from each other for 0-23 chromosomes.
There is an equal probability of each of the two siblings to get a chromosome from mother or father. Hence, irrespective of the variations provided by crossing over, random segregation of homologous chromosomes makes the two siblings differ from each other for 0-23 chromosomes.
Radon diffuses out of the earth in small, variable quantities all the time, but this can increase when reductions in pressure allows radon or fluids carrying I. Solution to escape to the surface, such pressure drops can accompany or precede the sharing of rocks in an earthquake!
Answer:
3 long tails : 1 short tail
Explanation:
This question involves a single gene coding for tail length in mice. The allele for long tail (T) is dominant over the allele for short tail (t). This means that an heterozygous mice will possess the long tail length.
According to this question, in a cross between two hybrid or heterozygote mice i.e. Tt × Tt, the following gametes will be produced by each parent:
Tt - T and t
Using these gametes in a punnet square (see attached image), the following will be produced: TT, Tt, Tt and tt.
Offsprings with genotype TT, Tt and Tt will have a LONG TAIL while genotype tt will have a SHORT TAIL. Hence, the phenotypic ratio will be 3 long tails : 1 short tail.