Genetics

In eukaryotic cells, the synthesis of RNA (transcription) primarily takes place in the nucleus.

• The DNA template, from which RNA is transcribed, is located within the nucleus.
• While mitochondria also contain their own DNA and can synthesize some RNA, the vast majority of cellular RNA synthesis occurs in the nucleus.

A pair of contrasting characters controlling the same trait is called allele.

Alleles are different forms of a gene that occupy the same position (locus) on homologous chromosomes.
For example, for the trait of flower color, there might be one allele for red flowers and another for white flowers.