AP BIOLOGY

Detailed explanation-1: -Mitochondria are special because they have their own ribosomes and DNA floating in the matrix. There are also structures called granules which may control concentrations of ions. Cell biologists are still exploring the activity of granules.

Detailed explanation-2: -Mitochondria and Plastids like Chloroplast have their own DNA and ribosomes because of which they are able to synthesize some of their own proteins and replicate independent of the nucleus.

Detailed explanation-3: -The mitochondrial matrix contains the mitochondrial DNA, ribosomes, soluble enzymes, small organic molecules, nucleotide cofactors, and inorganic ions.

Detailed explanation-4: -The matrix contains the deoxyribonucleic acid (DNA) of the mitochondrial genome and the enzymes of the tricarboxylic acid (TCA) cycle (also known as the citric acid cycle, or Krebs cycle), which metabolizes nutrients into by-products the mitochondrion can use for energy production.

Detailed explanation-5: -Detailed Solution. The correct answer is Mitochondria and Plastids. Both mitochondria and chloroplasts contain their own DNA and ribosomes. Both plant cells and animal cells possess mitochondria.