Which genetic material is a small circular molecule in mitochondria inherited maternally?

Which genetic material is a small circular molecule in mitochondria inherited maternally?

• A. Genotype
• B. Ancient DNA
• C. Mitochondrial DNA (mtDNA)
• D. Phenotype

Answer: (C)

Mitochondrial DNA is the genetic material inside mitochondria and is a small circular molecule. In humans, this genome is separate from the nuclear genome and consists of about 16,500 base pairs that encode a set of genes essential for the cell’s energy production. It is inherited almost exclusively from the mother because the mitochondria in sperm are typically not transmitted to the embryo, so the zygote’s mtDNA comes from the egg’s cytoplasm. This maternal inheritance pattern makes mtDNA a useful marker for tracing maternal lineages and studying ancient DNA. Other terms listed refer to broader concepts rather than a genetic material located in mitochondria—genotype is about genetic makeup, ancient DNA is DNA recovered from old samples, and phenotype is the observable traits—so they don’t describe the mitochondrial genome itself.

Mitochondrial DNA is the genetic material inside mitochondria and is a small circular molecule. In humans, this genome is separate from the nuclear genome and consists of about 16,500 base pairs that encode a set of genes essential for the cell’s energy production. It is inherited almost exclusively from the mother because the mitochondria in sperm are typically not transmitted to the embryo, so the zygote’s mtDNA comes from the egg’s cytoplasm. This maternal inheritance pattern makes mtDNA a useful marker for tracing maternal lineages and studying ancient DNA. Other terms listed refer to broader concepts rather than a genetic material located in mitochondria—genotype is about genetic makeup, ancient DNA is DNA recovered from old samples, and phenotype is the observable traits—so they don’t describe the mitochondrial genome itself.