4.1.3 Mitochondria & Chloroplast DNA

Features of Mitochondrial and Chloroplast DNA:

1. Structure:

• DNA in mitochondria and chloroplasts is short, circular, and not associated with histone proteins, similar to prokaryotic DNA.

2. Location:

• Mitochondrial DNA is found in the mitochondria and encodes proteins essential for aerobic respiration, such as enzymes in the electron transport chain.
• Chloroplast DNA is found in the chloroplasts and encodes proteins and enzymes required for photosynthesis, such as those in the light-dependent and light-independent reactions.

3. Function:

• Both types of DNA enable these organelles to produce some of their own proteins independently of the nucleus.

4. Inheritance:

• Mitochondrial DNA is maternally inherited (passed down from the mother).
• This makes mitochondrial DNA useful for tracing maternal ancestry.

Key Terms:

• Mitochondrial DNA (mtDNA): DNA found in mitochondria, coding for respiratory enzymes.
• Chloroplast DNA: DNA found in chloroplasts, coding for photosynthetic enzymes.
• Maternal Inheritance: The transmission of mitochondrial DNA exclusively from the mother.