Question

How is a new mitochondria formed by the pre-existing ones? (a) Mitosis (b) Fission (c) Conjugation (d) Budding

Short answer

New mitochondria are formed from pre-existing ones through (b) Fission. Mitochondria replicate via a kind of binary fission, not by mitosis, conjugation, or budding.

Step-by-step solution

Understanding the options

First, it's important to discuss each alternative: (a) Mitosis is the process of cell division in eukaryotic cells; it doesn't concern organelles like mitochondria. (b) Fission is a type of asexual reproduction in single-celled organisms. However, it's also used to describe the process of cellular organelles division, including mitochondria. (c) Conjugation is a process of DNA exchange between two cells, which doesn't apply to organelle reproduction. (d) Budding is a form of asexual reproduction where a new organism grows out of the parent. This isn't applicable to mitochondria.

Linking the Options to the Mitochondrial Division

It can therefore be concluded that mitosis, conjugation, and budding do not fit with the division of mitochondria. Instead, mitochondria replicate via a kind of binary fission, which is why (b) 'Fission' is the only correct answer in this context.

Final Answer

Having examined all four possibilities, the conclusion is that 'Fission' is the process by which new mitochondria are formed from pre-existing ones.