Prokaryotes lack an organized nucleus and other membrane-bound organelles. Prokaryotic DNA is found in a central part of the cell called the nucleoid. The cell wall of a prokaryote acts as an extra layer of protection, helps maintain cell shape, and prevents dehydration.

**Prokaryotic Cell: Structure and Characteristics**

A prokaryotic cell is a type of cell that lacks a true nucleus and membrane-bound organelles. It is typically smaller and simpler in structure compared to eukaryotic cells. Here, we will discuss the characteristics of a prokaryotic cell and explain why option 'D' is the correct answer.

**1. Absence of Nucleus:**
- Prokaryotic cells lack a true nucleus. Instead, they have a region called the nucleoid, which contains the genetic material (DNA).
- The nucleoid is not enclosed by a nuclear membrane, unlike the nucleus in eukaryotic cells.

**2. Absence of Membrane-bound Organelles:**
- Prokaryotes do not possess membrane-bound organelles such as mitochondria, plastids, endoplasmic reticulum, and Golgi bodies.
- Mitochondria are responsible for cellular respiration and energy production, while plastids are involved in photosynthesis in plant cells.
- Endoplasmic reticulum is involved in protein synthesis and lipid metabolism, and Golgi bodies are responsible for protein modification and packaging.

**3. Presence of Cell Wall:**
- Prokaryotic cells are surrounded by a cell wall, which provides structural support, protection, and shape to the cell.
- The cell wall of prokaryotes is primarily composed of peptidoglycan, a unique polymer that is absent in eukaryotic cells.

**4. Presence of DNA Fibrils:**
- The genetic material in prokaryotic cells is present in the form of DNA fibrils or circular DNA molecules.
- These DNA fibrils are located in the nucleoid region and are not associated with histone proteins, as seen in eukaryotic cells.

**5. Absence of Spindle Fibers:**
- Prokaryotic cells lack spindle fibers, which are responsible for the movement and separation of chromosomes during cell division (mitosis).
- Instead, prokaryotes undergo a simpler form of cell division called binary fission, where the DNA is replicated and distributed to daughter cells.

**6. Absence of Golgi Bodies:**
- Golgi bodies, also known as Golgi apparatus, are involved in the modification, packaging, and sorting of proteins in eukaryotic cells.
- Prokaryotic cells do not possess Golgi bodies. Instead, they have simpler sorting mechanisms for protein transport.

**7. Absence of Endoplasmic Reticulum:**
- Endoplasmic reticulum (ER) is a membranous network involved in various cellular processes such as protein synthesis, lipid metabolism, and calcium storage.
- Prokaryotic cells lack endoplasmic reticulum. They have a simpler and less extensive internal membrane system.

In conclusion, the correct answer is option 'D' because prokaryotic cells lack endoplasmic reticulum, Golgi bodies, and spindle fibers, while they possess a cell wall, DNA fibrils, and a nucleoid region instead of a true nucleus.

All that projaryotic organisms lack membrane bound organelles. they lack true nucleus i.e. nuclear membrane, mitochondria, golgi body, endoplasmic reticulum, vacuoles, lysosomes and others because they are membrane bound organelles. now cell division in prokaryotic organisms occurs by the process of amitosis which does not include spindle fibre formation. chromosomes do not differentiate. the nucleus elongates and constricts in the middleand divides into 2 daughter nuclei. so prokaryotic cell does not contain er, golgi body and also does not form spindle fibres