A Genuine Hybridizer With Silky Seeds?

Gregor Mendel’s experiments on inheritance patterns involved crossing true-breeding plants for violet flower color with true-breeding plants for white flower color (the P generation). The resulting hybrids in the F1 generation all had violet flowers. Mendel developed three principles of inheritance that described the transmission of genetic traits before anyone knew exactly. A true-breeding plant is one that, when self-fertilized, only produces offspring with the same traits. True-breeding organisms are genetically identical and have identical alleles for specified traits.

To demonstrate this, Mendel crossed a pure-breeding round-seeded variety with a pure-breeding wrinkled-seeded one. The parents (designated the P generation) were pure-breeding because each was homozygous for the trait. When a true-breeding plant with smooth seeds is crossed with a true-breeding plant with wrinkled seeds, all the offspring produced will be smooth.

True-breeding plants produce offspring with the same genotypes in their gametes. The genotype of parent plants is heterozygous, as it is given that the smooth seeds are dominant over the wrinkled seed. In the F1 generation, true-breeding plants with round and yellow seeds are the dominant traits. The F1 plants were allowed to self-fertilize, and the resulting hybrids in the F1 generation all had violet flowers.

Do true breeding pea plants always produce offspring?

Mendel’s model system was developed using the garden pea, Pisum sativum, to study inheritance. The pea naturally self-fertilizes, producing highly inbred, or “true-breeding” plants that always produce offspring that look like the parent. This allowed Mendel to avoid unexpected traits in offspring that might occur if the plants were not true breeding. The garden pea grows to maturity within one season, allowing for several generations to be evaluated over a relatively short time.

Mendelian crosses involved hybridizations, where two true-breeding individuals with different traits were mating. In the pea, pollen transfers male gametes to the stigma, a sticky organ that traps pollen and allows sperm to move down the pistil to the female gametes. To prevent the pea plant from self-fertilizing, anthers were removed from the plant’s flowers before they had a chance to mature.

Plants used in first-generation crosses were called P 0, or parental generation one, plants. Mendel collected seeds from these plants and grew them the following season, producing the F 1, or first filial generation. After examining the characteristics in the F 1 generation, he allowed them to self-fertilize naturally, and then collected and grew the seeds from the F 1 plants to produce the F 2, or second filial generation.

Mendel’s experiments extended beyond the F 2 generation to the F 3, and F 4 generations, but the ratio of characteristics in the P 0 −F 1 −F 2 generations was the most intriguing and became the basis for his postulates.

What plants breed true?

Mendel’s experimental work on inheritance was successful due to the easy manipulation of pea plant reproduction and its ability to grow to maturity within one season. The garden pea, which has both male and female parts, can self-pollinate or cross-pollinate with other plants. In the absence of outside manipulation, the plant naturally self-fertilizes, with ova fertilized by pollen from the same flower. The sperm and eggs that produce the next generation of plants both come from the same parent.

The flower petals remain sealed until after pollination, preventing pollination from other plants. This results in highly inbred, or “true-breeding” pea plants, which always produce offspring that look like the parent. Today, we know that these “true-breeding” plants are homozygous for most traits.

What is an example of a true breeding plant?

The term “true breeding” is used to describe a process whereby any resulting crosses will produce offspring with the same phenotype, indicating that every gene is homozygous. This phenomenon can be observed in a purple plant crossing itself.

What is the allele for smooth seeds?

The shape of pea seeds is determined by two alleles: the dominant S allele, which is associated with smoothness, and the recessive S allele, which is linked to wrinkledness.

Are smooth seeds dominant or recessive?

The dominant seeds of a plant are typically smooth and green, whereas the dominant seeds of another plant may be wrinkled and orange. When a plant homozygous for smooth and green seeds is crossed with a plant with wrinkled and orange seeds, the resulting offspring are self-crossed.

What is the probability that a cross between a true breeding pea plant with smooth seeds?

The progeny of a true-breeding pea plant cross with smooth seeds (S) and wrinkled seeds (s) exhibits a 100% probability of having smooth seeds, as smooth seeds are dominant.

Which seeds are smooth?

The seeds that are characterized by a smooth texture include mustard seed, apple seed, and watermelon seed.

What is the offspring of a cross between two true breeding pea plants with smooth seeds?

The F1 generation will produce all offspring with a dominant characteristic of smooth seed, as this is the preferred trait.

What are pure breeding plants?

True-breeding or pure breeding plants are genetically identical to the character(s) being investigated, resulting in offspring with the same traits. They undergo self-fertilization for several generations, ensuring their traits remain unchanged. Pure breeds do not show variations and transmit the same traits for several generations upon self-pollination. Cross-pollination typically does not produce pure breeds, but may allow for the expression of new or suppressed traits in offspring.

Is a true breeding line of green pod pea plants crossed with a true breeding line of yellow pod plants?

The green pea pod, which is a result of pure breeding, is crossed with a true-breeding line of a yellow pea pod, resulting in offspring that are green, in accordance with the law of dominance, which states that green is dominant.

What happens when two true breeding plants are crossed?

Plants that are true-breeding, also referred to as homozygous, produce offspring that are identical to themselves when self-pollinated. This classic Mendelian inheritance pattern occurs when parents with two different traits (one for green seeds and one for yellow seeds) are crossed.