**In prokaryotes, the reserved food material is stored in the cytoplasm.**

**Explanation:**

Prokaryotes are unicellular organisms that lack a true nucleus and membrane-bound organelles. Their genetic material is present in the form of a single circular DNA molecule located in the nucleoid region. Prokaryotes also have a cytoplasm, which is a gel-like substance that fills the cell.

The reserved food material in prokaryotes is stored in the cytoplasm. This serves as a source of energy and nutrients for the cell during periods of scarcity or unfavorable conditions. There are different ways in which prokaryotes store food in their cytoplasm:

1. **Inclusion bodies**: Some prokaryotes store reserve food materials in the form of inclusion bodies. These are distinct granules or bodies that are observed under the microscope. Examples of inclusion bodies include glycogen granules, which store glucose molecules, and polyhydroxybutyrate granules, which store carbon and energy.

2. **Gas vesicles**: Certain prokaryotes, such as cyanobacteria, have gas vesicles in their cytoplasm. These vesicles provide buoyancy to the cell and allow it to float in water. The gas vesicles also serve as storage compartments for gases, such as oxygen or nitrogen, which can be used by the cell when needed.

3. **Magnetosomes**: Some prokaryotes, such as magnetotactic bacteria, have magnetosomes in their cytoplasm. Magnetosomes are membrane-bound organelles that contain magnetic minerals, such as magnetite or greigite. These organelles allow the bacteria to detect and align with the Earth's magnetic field. They can also store iron, which is an essential nutrient for the cell.

It is important to note that while prokaryotes store food material in their cytoplasm, they do not have a dedicated organelle like the vacuole in eukaryotes for storing reserves. The cytoplasm acts as a multipurpose space, accommodating various cellular processes, including the storage of food materials.