A mushroom or a mold commonly reproduces asexually by the formation of spores. Spores are produced in the sporangium through mitosis involving only one parent. They are released from the parent and germinate into new a mushroom or a mold. The offspring are genetically identical to that parent because their formation do not involve meiosis and fertilization. Spores allow fungi to expand their distribution and colonize new environments.
The greatest amount of genetic variation is a sexual population is due to the processes of meiosis and mutation. Meiosis increases the genetic variation because of the recombination and independent assortment in the process, such that each gamete contains a different set of DNA, therefore the zygote produced during fertilization has a unique combination of genes.<span />
Answer:
The ratio of blue to white offspring in the progeny is 4 blue : 12 white.
Explanation:
<u>Available data:</u>
- The dominant allele K is necessary to synthesize blue flower pigment
- K is inhibited by the dominant allele D
- Plants with the genotype K- D- will not produce pigment (and their flowers will be white)
Cross: testcross for (Kk Dd) plants
Parental) KkDd x kkdd
Gametes) KD kD Kd kd
kd kd kd kd
Punnet square) KD Kd kD kd
kd KkDd Kkdd kkDd kkdd
kd KkDd Kkdd kkDd kkdd
kd KkDd Kkdd kkDd kkdd
kd KkDd Kkdd kkDd kkdd
- Whenever D is present, it inhibits the expression of the K gene, so every plant with the dominant D allele will be white. This plants´ genotype is kkD- or K-D-.
- Whenever D is absent and K is present, every plant with genotype K-dd will be blue.
- The recessive form for K and D genes will express white-flowered plants, with genotype ddkk
F1) Progeny genotype: 4/16 KkDd, white-flowered plants
4/16 Kkdd, blue-flowered plants
4/16 kkDd, white-flowered plants
4/16 kkdd, white-flowered plants
The ratio of blue to white offspring in the progeny is 4 blue : 12 white.
Blue-flowered plants: 4 Kkdd
White-flowered plants: 4 KkDd + 4 kkDd + 4 kkdd