Difference Between Nucleus and Nucleoid

Inside every living organisms, there is an area that stores all the genetic material and controls cellular activities. In eukaryotes, this function is taken up by the nucleus, whereas in prokaryotes, the same is undertaken by the nucleoid.

What is a Nucleoid?

By definition, a nucleoid is a region within a prokaryotic cell that contains most or all of the genetic material. This material is called the genophore or the prokaryotic chromosome.

DNA is found in both the nucleus and nucleoid. And hence, the functions of the nucleus and nucleotide are almost the same. However, their structure and organisation differ in many ways.

Also Read: The Nucleus

Difference Between Nucleus and Nucleoid

The nucleus is the largest and the most important cell organelle in a eukaryotic cell. A nucleus is a membrane-bound organelle that houses the genetic material of eukaryotes in DNA. The nucleus consists of protein fibres or the DNA inside chromatin fibres. Nucleoids contain the genetic material of prokaryotes in the cytoplasm. The nucleoids usually consist of a single chromosome. Let us look at more difference between nucleus and nucleoid in the table given below.

Nucleus Nucleoid
A nucleus is a membrane-bound structure in which eukaryotes store their genetic materials. Nucleoid is a particular area in which prokaryotes store their genetic materials.
A nucleus is well organised and is large. Nucleoid is poorly organised and is small.
A nucleus is surrounded by a double layer membrane called nuclear membrane which separates the nucleus from other cell organelles. Nucleoid lacks a protective membrane.
A nucleus contains many chromosomes. Nucleoid usually contains only one chromosome.
A nucleus is a spherically shaped organelle. Nucleoid is an irregularly shaped organelle.
Nucleoplasm and Nucleolus are present in the nucleus. Nucleoplasm and Nucleolus are absent in a nucleoid.
It is composed of DNA, RNA, enzymes, dissolved ions, histones and other subnuclear bodies. It is composed of DNA, RNA, histones and other proteins.

From the differences given, we can conclude that the nucleus and nucleoid are different in many ways. Explore other important topics such as the structure of DNA, RNA, or any other related topics by registering at BYJU’S.

Important Questions about Difference Between Nucleus and Nucleoid

1. In what type of organisms are the nucleus and nucleoid found?

The nucleus is explicitly found in eukaryotic organisms while nucleoids are found only in prokaryotes. These structures essentially contain the genetic material and DNA is found in both the nucleus and nucleoid.

2. How are the nucleus and nucleoid protected inside the cell?

The nucleus found inside eukaryotic cells are is protected by the nuclear membrane. It separates the nucleus from the other cellular components inside the cell. The nucleoid possesses no such protective membrane and is not separated from the other components of the prokaryotic cell.

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