Mendel's Law of Dominance states that in a heterozygote, one allele (the dominant one) will mask the presence of the other (the recessive one) in the phenotype. The recessive trait only appears in the phenotype when the organism is homozygous for the recessive allele.

Gregor Mendel conducted his famous hybridization experiments using the garden pea, Pisum sativum. He chose this plant because it was easy to grow, had distinct contrasting traits, and allowed for controlled self-pollination and cross-pollination.

Mendel chose garden peas because they are easy to grow, have a short generation time, and produce many offspring. Crucially, they possess bisexual flowers that naturally self-pollinate, allowing Mendel to create pure-breeding lines. This structure also made it easy for him to perform controlled cross-pollination by manually transferring pollen between specific plants to study inheritance patterns.

Pleiotropy is a fundamental concept in genetics where a single locus influences multiple, often unrelated, phenotypic traits. This occurs because the protein encoded by the gene may function in different metabolic pathways or be required in various cell types. Understanding pleiotropy is essential for analyzing complex genetic disorders where a single mutation results in a syndrome of diverse symptoms.

In sexual reproduction, an offspring inherits one complete set of chromosomes from the mother's egg and one complete set from the father's sperm. Since each set contains a corresponding number of genes, the total number of genes inherited from each parent is equal, maintaining the diploid nature of the organism.

Penetrance refers to the percentage of individuals with a particular genotype that exhibit the corresponding phenotype. If a genotype is always expressed, it is said to have complete penetrance. If only a fraction of the population with the genotype shows the trait, it is termed incomplete penetrance. This concept is fundamental in understanding how specific genetic variants manifest in clinical and biological contexts.

A gene is defined as the basic physical and functional unit of heredity. Genes are composed of specific sequences of DNA that act as instructions to make molecules called proteins. While chromosomes are the structures that contain these genes and the nucleus is the organelle housing the DNA, the gene itself is the specific unit responsible for the inheritance of traits.

Gregor Mendel is known as the father of genetics for his pioneering experiments with pea plants. He formulated the fundamental laws of inheritance, specifically the Law of Segregation and the Law of Independent Assortment. His work provided the mathematical framework for understanding how traits are passed from parents to offspring, laying the foundation for modern genetics.

Gregor Mendel's laws of inheritance are based on the segregation and independent assortment of alleles during gamete formation. These processes are unique to sexual reproduction, where the fusion of haploid gametes from two parents results in offspring with new combinations of genetic traits.

In genetics, penetrance refers to the proportion of individuals with a genotype who show the phenotype, while expressivity refers to the degree to which a trait is expressed. The chlorophyll deficiency in Lima beans is known to show both incomplete penetrance (not all individuals with the gene show the trait) and variable expressivity (the severity of the deficiency varies among those who do).