1. How many different phenotypes are possible in the offspring of two parents with genotypes AA and aa, where A is the dominant allele for a trait and a is the recessive allele for the same trait? (1 point)one
two
three
four

2. A woman buys red-flowering and blue-flowering plants of the same species and plants them in her garden. The plant undergoes both self-fertilization and cross-fertilization. The woman collects seeds and plants them the following spring. What can the woman expect to observe in the flowers of the new generation of plants if the gene for flower color is codominant? (1 point)
plants with red flowers and plants with blue flowers
plants with both red and blue flowers
plants with red flowers, plants with blue flowers, and plants with purple flowers
plants with purple flowers
3. What is formed at the end of meiosis? (1 point)
two genetically identical cells
four genetically different cells
four genetically identical cells
two genetically different cells

Respuesta :

one 
Phenotype is how it expressed. All will get at least one of the dominant A alleles so the dominant trait would be expressed in all of them. 
elf fertilization would give the blue and red. Some of the crosses would be between blue and red and since it is codominant both alleles are expressed so it could be a blending
four genetically different cell

Answer:

1. One

2. plants with both red and blue flowers

3. four genetically different cells

Explanation:

QUESTION 1

According to the law of DOMINANCE proposed by Mendel, one allele called the DOMINANT allele is capable of masking the expression of another allele called RECESSIVE allele, in the same gene. In this case, A is the dominant allele while a is the recessive allele. Therefore, in a cross between AA parent and aa parent, A and a gametes will be produced respectively.

These gametes will combine to form offsprings with "Aa" genotype i.e. one phenotype.

QUESTION 2:

CODOMINANCE is a genetic phenomenon whereby one allele is neither dominant nor recessive over the other instead they are both phenotypically expressed in the individual organism. This is the case here, if the flower gene exhibits co-dominance, it means that the red flower allele and the blue flower allele will be simultaneously expressed. The woman is expected to have plants with both red and blue flower colour in the next generation due to this co-dominance.

QUESTION 3:

Meiosis is one of the two cellular divisions in which four daughter cells (gametes) are produced with each having a reduced number of chromosomes (by half). Meiosis occurs in a two-step division process in order to reduce the chromosomal number of the parents. This two divisions results in the formation of four daughter cells.

A phenomenon called CROSSING-OVER is unique to meiosis where chromosomal segments are exchanged between non-sister chromatids of homologous chromosomes. This increases the chance of genetic diversity among species i.e. daughter cells will contain a different genetic combinations as the parents.

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