02 Mendel: Mendelian Genetics

Mendel used the garden pea for his experiments. This is because the garden pea (Pisum sativum) is a well-known and widely used model organism in genetics. It has several advantages such as a short generation time, easy cultivation, and clear observable traits that can be easily manipulated and studied. Mendel conducted his experiments on pea plants to study the patterns of inheritance and establish the principles of heredity, which laid the foundation for modern genetics.

The correct answer is "an Austrian Augustinian monk." This is because Mendel is widely known for his work in the field of genetics, where he conducted experiments on pea plants to study inheritance patterns. He was not a rock star or a televangelist, and there is no information given about him being Dr. Johnson's former student. Therefore, the correct option is that he was an Austrian Augustinian monk.

In one of Mendel's monohybrid crosses, 50% of the F2 progeny were heterozygous. This means that half of the offspring inherited one dominant allele and one recessive allele for the trait being studied. Mendel's experiments with pea plants showed that when two different alleles are crossed, the dominant allele is expressed in the phenotype while the recessive allele remains hidden. Therefore, in this particular cross, half of the F2 progeny exhibited the dominant trait while carrying one recessive allele.

In one of Mendel's monohybrid crosses, 25% of the F2 progeny showed the recessive phenotype. This means that out of every 100 offspring, 25 displayed the recessive trait. This result is consistent with Mendel's law of segregation, which states that each individual inherits two alleles for a trait, one from each parent, and that these alleles segregate or separate during gamete formation. Consequently, there is a 25% chance that an individual will inherit two recessive alleles and express the recessive phenotype.

In one of Mendel's monohybrid crosses, 25% of the F2 progeny were homozygous recessive. This means that out of all the offspring in the second filial generation, a quarter of them exhibited the recessive trait. This result is in accordance with Mendel's law of segregation, which states that when two alleles for a trait are crossed, they separate and are distributed randomly into the offspring.

In one of Mendel's monohybrid crosses, 75% of the F2 progeny showed the dominant phenotype. This means that out of every 100 offspring, 75 exhibited the dominant trait. This result is consistent with Mendel's law of segregation, which states that when two alleles for a trait are crossed, the dominant allele will be expressed in the offspring more frequently than the recessive allele.

In one of Mendel's dihybrid crosses, 1/16 of the F2 progeny showed the recessive phenotype for both traits. This can be explained by the fact that each trait is governed by a separate gene and follows the principles of independent assortment. In this case, the recessive alleles for both traits must have been present in the parents and independently segregated in the F1 generation. The probability of both recessive alleles coming together in the F2 generation is 1/16, which is the numerator of the given fraction.

Mendel's conclusion that alleles separate and enter different gametes is known as his Law of Segregation. This law states that during gamete formation, the two alleles for each trait separate and only one allele is passed on to each offspring. This explains how traits are inherited and why offspring can have different combinations of alleles from their parents.

In Mendel's monohybrid cross between yellow cotyledons and green cotyledons, all of the F1 progeny were yellow. This is because yellow cotyledons are dominant over green cotyledons. Therefore, when the yellow cotyledons are crossed with green cotyledons, all of the F1 progeny inherit the yellow cotyledon trait.

In one of Mendel's monohybrid crosses, 100% of the F1 progeny were heterozygous. This means that all of the offspring inherited one dominant allele and one recessive allele for the trait being studied. Mendel's experiments with pea plants demonstrated the principle of segregation, where the two alleles for a trait separate during gamete formation and then randomly recombine during fertilization. As a result, all of the F1 progeny in this particular cross ended up being heterozygous for the trait.

During Mendel's time, many scientists believed that the inheritance of traits from parents was due to the mixing of the two parents' blood or sap. This misconception arose because blood and sap were seen as vital fluids that carried traits and characteristics. However, Mendel's experiments with pea plants disproved this theory and instead demonstrated that traits were inherited through discrete units, which we now know as genes. Mendel's work laid the foundation for the modern understanding of genetics.

In one of Mendel's dihybrid crosses, 4/16 of the F2 progeny were heterozygous for both genes. This can be determined by using the Punnett square to analyze the possible genetic combinations. Since there are 16 total combinations possible (4 for each gene), and 4 of those combinations result in heterozygosity for both genes, the numerator of the fraction is 4.

Mendel's conclusion that the separation of one pair of alleles does not influence the separation of another pair of alleles is known as his Law of Independent Assortment. This means that the inheritance of one trait is not dependent on the inheritance of another trait. Each pair of alleles segregates independently during gamete formation, leading to a random assortment of alleles in the offspring. This law explains the variety of traits observed in offspring and is a fundamental principle of genetics.

The mistaken idea that life routinely arose from non-living material was known as spontaneous generation. This theory proposed that living organisms could emerge spontaneously from non-living matter, such as maggots appearing on decaying meat. However, this theory was eventually disproven through scientific experiments, such as Louis Pasteur's swan-neck flask experiment, which demonstrated that life only arises from preexisting life through the process of biogenesis.

In one of Mendel's dihybrid crosses, 9/16 of the F2 progeny showed the dominant phenotype for both traits. This can be determined by using the Punnett square method to calculate the possible genotypes and phenotypes of the offspring. The dominant phenotype is expressed when at least one dominant allele is present for both traits. In this case, out of the 16 possible combinations in the F2 generation, 9 of them resulted in the dominant phenotype for both traits.

In Mendel's dihybrid cross, the numerator of the fraction representing the number of F2 yellow/smooth progeny that were homozygous for both genes is 1. This means that out of the total number of F2 yellow/smooth progeny, only 1 of them had both genes in a homozygous state.

In Mendel's dihybrid cross, when yellow and smooth traits are crossed with green and wrinkled traits, the genotype of the F2 yellow/smooth progeny can be determined using the Punnett square. The possible genotypes for the F2 generation are YYSS, YYss, YySS, Yyss. Out of these four genotypes, only one genotype (YySS) is heterozygous for both genes. Therefore, the numerator of the fraction representing the F2 yellow/smooth progeny that are heterozygous for both genes is 1.

The mistaken idea that the sperm or egg contained a miniature, fully-developed human (a homunculus) was the theory of preformation. This theory suggested that all the characteristics of an individual were already present in the sperm or egg, and that development involved the growth and unfolding of these preexisting structures. This theory was popular in the 17th and 18th centuries but was eventually disproven with the discovery of fertilization and the understanding of genetic inheritance.

In Mendel's dihybrid cross, the ratio of yellow/smooth progeny that were heterozygous for just one gene is 4/9. This means that out of 9 progeny, 4 of them had the genotype for either yellow or smooth, but not both. This can be explained by the principle of independent assortment, where alleles for different traits segregate independently during gamete formation. Therefore, there is a 4/9 chance that a progeny will inherit only one of the alleles for either yellow or smooth traits.

The correct answer is Independent Assortment. Independent Assortment is one of Mendel's Laws that states that during gamete formation, the alleles for different traits segregate independently of each other. This means that the combinations of alleles in the gametes are random and occur in equal proportions. In a dihybrid cross, where two traits are being studied, the alleles for each trait segregate independently, resulting in the formation of four types of gametes in equal proportion.

Correns, de Vries, and Tschermak were the three scientists who independently rediscovered and confirmed Gregor Mendel's work on inheritance in 1900. They each published their findings around the same time, thus leading to the recognition of Mendel's groundbreaking contributions to the field of genetics.

In Mendel's monohybrid cross, when yellow cotyledons are crossed with green cotyledons, 33% of the F2 yellow seeds were homozygous. This means that out of the total F2 yellow seeds, 33% of them had both alleles for yellow cotyledons.

In Mendel's monohybrid cross, when yellow cotyledons are crossed with green cotyledons, the F1 generation will all have the genotype for yellow cotyledons (YY). When the F1 generation is crossed with each other, there will be a 25% chance of producing yellow seeds with the genotype YY, as there are four possible combinations of genotypes (YY, Yy, yY, yy) and only one of them will result in yellow seeds. Therefore, 25% of the F2 yellow seeds will have the same genotype as the F1 seeds. Converting 25% to a whole number gives us 67.

Lamarckism is a theory that suggests that acquired characteristics can be inherited by offspring. This means that traits or characteristics acquired by an organism during its lifetime can be passed on to its offspring. Lamarckism contradicts the principle of inheritance based on genetics, which is the transmission of traits through genes. Lamarckism proposes that changes in an organism's behavior or environment can lead to changes in its physical traits, which can then be inherited by future generations.