D is the answer. A gene is a part of a chromosome.
A sarcomere is the basic contractile unit of muscle fiber. Each sarcomere is composed of two main protein filaments—actin and myosin—which are the active structures responsible for muscular contraction. The most popular model that describes muscular contraction is called the sliding filament theory.
Enzymes are proteins that catalyze biochemical reactions within cells
Answer:
<h2>
The Nucleus.</h2>
Explanation:
The structure most necessary for a mitochondria to produce new cells is the nucleus.
The nucleus is a very specialized structure that occurs in most cells including the mitochondria.
It is a membrane bound organelle that contains genetic materials which is the DNA of all eukaryotic organisms(multicellular organisms)
It plays important functions such as:
1. Primarily an information center of the cell
2.Metabolism roles
3. Growth and production of new molecules in the mitochondria(mitochondrial bio-genesis).
