Monoploid organisms reproduce asexually since they need to transmit all of their genetic material to their offspring. Diploid organisms, have 2 copies of their genetic material that differ slightly in their genes. Since the progeny gets half of the DNA from each parent, we have that new combinations can emerge; for example, if the mother is AA for some allele and the father aa, their offspring will be Aa, a new genotype. This might have different implications (for example, the recessive gene for thalassemia also provides resistance to malaria). Finally, during meiosis, there is also an event called crossover that increases the genetic variation of the offspring.

3 0

3 years ago

Gray seed color in peas is dominant to white. Assume that Mendel conducted a series of experiments where plants with gray seeds

bazaltina [42]

Answer:

(a) Gg × Gg; (b) genotypic = 1:2:1, phenotypic = 3:1

Explanation:

a) A cross between two gray seeded plants produces progeny with gray and white seeds in 3:1 ratio (302:98=3:1). This means that the parent plants are heterozygous and each has at least one recessive allele. If the allele "G" is responsible for gray seed and the allele "g" imparts white color to the seeds, the genotype of the heterozygous parents would be "Gg".

b) A cross between two heterozygous gray seeded parents would produce progeny in following ratio:

Genotype ratio= 1 GG: 2 Gg: 1 gg

Phenotype ratio= 3 Gray: 1 white

4 0

3 years ago