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the seeds in this exercise were produced by a heterozygous parent and homozygous recessive parent as described in step 4. list all possible crosses that could have produced the homozygous recessive parent (cc).

User Tishana
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Final answer:

There are two potential crosses that could produce a homozygous recessive (cc) offspring: a cross between two homozygous recessive parents (cc x cc) or between a homozygous recessive and a heterozygous parent (Cc x cc). Mendelian genetics and Punnett squares help determine possible genotypic outcomes.

Step-by-step explanation:

The question focuses on understanding the possible genetic crosses that could produce a homozygous recessive parent (cc) in the context of Mendelian genetics.

Considering that the homozygous recessive parent is a product of its previous generation, we can hypothesize its parents' genotypes.

Two potential crosses could produce a homozygous recessive (cc) offspring: cross between two homozygous recessive parents (cc x cc), or a cross between a homozygous recessive parent (cc) and a heterozygous parent (Cc).

Each of these crosses involves different combinations of recessive alleles and could produce the homozygous recessive phenotype.

Furthermore, using a Punnett square, if we cross a homozygous recessive cc with a heterozygous Cc, there is a 50% chance to produce a homozygous recessive offspring (cc).

Conversely, crossing two homozygous recessive individuals (cc x cc) would always result in a homozygous recessive offspring (cc).

Mendelian genetics demonstrates that inheritance follows predictable patterns and that the genotypic and phenotypic ratios can be calculated when the genetic composition of the parents is known.

User Chrisber
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2 votes

Final answer:

To produce a homozygous recessive individual (cc), two possible crosses are either two homozygous recessive individuals (cc x cc) or a heterozygous and a homozygous recessive individual (Cc x cc or cC x cc). All of these crosses can potentially yield homozygous recessive offspring.

Step-by-step explanation:

The student asked what possible genetic crosses could have produced a homozygous recessive parent (cc) in the context of Mendelian genetics. A homozygous recessive genotype, like cc, can arise from several crosses. These include:

  • Crossing two homozygous recessive parents (cc x cc), which always results in homozygous recessive offspring.
  • Crossing a heterozygous parent carrying the recessive allele with a homozygous recessive parent (Cc x cc or cC x cc), which has a 50% chance of producing homozygous recessive offspring.

It is important to note that each parent contributes one allele to the offspring, and fertilization is a random event. Therefore, every combination of alleles is equally likely provided that the parents have those alleles to pass on.

User Pete Amundson
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