Mendel crossed a pea plant with purple flower with white flower
i.write the genotype of P1 generation
ii.what are gamates of P1
iii. write the phenotype and genotype of F1 generation iv.write the gamets of F1 generation
v.Write down the phenotype and genotype of F2 generation with respective ratio
vi. What type of process is defined it
Answers
Answer:
Mendel studied several different traits of a pea plant. For example, some pea plants have purple flowers and others have white flowers. Pea plants can either self-fertilize or cross-fertilize. Crossing two plants is called hybridization. To start, however, Mendel needed plants that were true-breeding. This means that after generations of self-breeding, the pea plant expressed only one version of the trait. After many generations a purple flowered plant only produced plant never produced a white flowered plant.
Mendel then crossed a true-breeding purple flower plant and a true-breeding white flower plant. This is called a monohybrid experiment. A test cross is performed between two plants that breed true for one trait, and the resulting trait for each offspring plant is determined
A chart of a monohybrid experiment between a purple and white flower
The first, true-breeding generation, is called the parent, P generation. The first generation of offspring, the first filial generation, is the F1 generation. Mendel found that these plants all had purple flowers. The F1 generation was crossed with itself. The next generation, F2 generation, had a 3:1 ration of purple to white flowers.
If the blending hypothesis was correct, the F1 generation should have all had light purple flowers. Instead, all the F1 plants had dark purple flowers. How did Mendel explain the complete loss of the white flower characteristic in the first generation and its reappearance in the second generation?
The Law of Segregation
Mendel explained what he saw using the law of segregation. Each gene can have different alleles. For example, one gene determines flower color in pea plants. Different versions of that same gene are alleles. The two different alleles here are purple flowers and white flowers. Each plant has two copies of each gene: one copy from each parent plant. The F1 generation inherits a purple allele and a white allele. Even though the plant has one copy of each, we only see the trait from the purple flower gene. When a plant has one copy of each gene, the gene we see is the dominant allele. We indicate this with a capital letter for the allele, “P”. The gene that is masked by the dominant allele is recessive. Here the white allele is recessive, and we represent this using a lower case letter for the gene “p”.
The F1 plants all have one purple allele (P) and one white allele (p). The genotype is the alleles for each gene in the plant. Here the genotype is Pp. A plant with two of the same alleles is homozygous. A plant with two different alleles is heterozygous. The characteristic that we see with our eyes is the phenotype. For Pp, the phenotype is purple flowers.
This inheritance model is explained using a Punnett square.
A sample Punnett square created from a monohybrid cross of flowers
The law of segregation states that during gamete formation, the two genes each end up in different gametes. The gametes from each parent form a zygote, and the pairing of genes is random. The distribution of genes in the offspring is therefore dictated by probability. In a Punnett square, the alleles from one parent are written across the top and the genes from the other parent are written on the left side. Each box is filled with one allele from the top and one from the left. The ratio of genotypes for the offspring, is the ratio of genotypes from each of these boxes. The F1 generation is 100% Pp. The F2 generation is 25% PP (homozygous dominant, purple flowers), 50% Pp (heterozygous, purple flowers), and 25% pp (homozygous recessive, white flowers). This is how the white characteristic reappears in the second generation. The phenotype is 3:1, purple to white
Answer:
what she said
Explanation: