Examkin

Soru

Zorluk: KolayMendel's First Law and Monohybrid Inheritance

In a monohybrid cross between two heterozygous pea plants for flower position, 75%75\% of the F1F_1 offspring are expected to display the dominant phenotype.

Cevap: Cevap

Cevap

The statement is True.
The statement is accurate because crossing two heterozygous organisms (Aa×AaAa \times Aa) in a standard monohybrid cross with complete dominance results in a 3:13:1 phenotypic ratio, representing 75%75\% dominant and 25%25\% recessive phenotypes.

Adım Adım Çözüm

1
Identify the parental genotypes
Both parent plants are heterozygous (AaAa).
The stem specifies a monohybrid cross between two plants heterozygous for the trait.
2
Determine the offspring genotypic distribution using Mendel's Law of Segregation
The gametes (AA and aa) segregate to produce offspring with genotypes AAAA, AaAa, AaAa, and aaaa in a 1:2:11:2:1 ratio.
Each parent contributes one allele randomly to each offspring during fertilization.
3
Calculate the proportion of offspring expressing the dominant phenotype
Dominant phenotypes (AAAA and AaAa) constitute 33 out of 44 offspring, which equals 75%75\%.
The dominant allele (AA) completely masks the expression of the recessive allele (aa) in heterozygous genotypes.

Anahtar Kavram

Mendel's Law of Segregation and Monohybrid Cross Ratios
Bu soruyu puanla

Konular

Mendel's First Law and Monohybrid Inheritance

Bu konudan daha fazla soru