AP BIOLOGY

Detailed explanation-1: -Definition. Two chromosomes in a pair – normally one inherited from the mother and one from the father. For example, the two copies of Chromosome 1 in a cell would be referred to as homologous chromosomes.

Detailed explanation-2: -The tight pairing of the homologous chromosomes is called synapsis. In synapsis, the genes on the chromatids of the homologous chromosomes are aligned with each other.

Detailed explanation-3: -Thus, a pair of genes is called pair of alleles and it is referred as genotype. Humans are diploid organisms because they have two alleles at each genetic locus, one allele from the father and one allele from the mother.

Detailed explanation-4: -Heterozygous for a gene refers to when a homologous pair of chromosomes has different alleles of the same gene. A gene pair’s two alleles are found on homologous chromosomes. Alleles are a type of gene that differs from others.